IRLF 
 
 T H 
 
 

 REESE LIBRARY 
 
 OK THK 
 
 UNIVERSITY OF CALIFORNIA. 
 'ftefeiveJ 
 
 Accessions No. 
 
 
 
.. 
 
 : o/o*v J> 
 
 ''**%.*- ~ ?" 
 
 
 . 
 
 r> 
 
 m 
 
 ri ^\' 
 
 , 
 
 *&' 
 53g^, ' A W JS^ 
 
 ^j 
 
 !^^ 
 
 f ^^v 7 ' ^r ^^"^ t~ *n ^3^^ >L VT ;?2F'-- 
 
 ^1^,^dk -^%^fe ^W% A 
 
 : x^-> +^r ^^r <^o^*o v^- 
 v x ^^ %-v^r, ^ 
 
 ce^ 
 
 " ^ ^L' ^ 
 
 ?w 
 
 ^ 'i^H 
 
 ^* 
 
 ^ 
 
 <? ^^<i ^S5r^SnG3 t>c- *^l JV^T^.iSaG TVs- ^^T A^Srl 
 
 ^K 
 
 
 
 
 . 
 
ROOF FRAMING MADE EASY 
 
 BY 
 
 OWEN B. MAGINNIS, 
 
 Instructor of Drawing in New York Trade School. 
 
 Author of "How to Frame a House," "Practical Centring," " How to Join Moldings," etc. 
 
 A practical and easily comprehended system of laying out and framing 
 roofs, adapted to modern construction. The methods are 
 made clear and intelligible by 76 engravings 
 with extensive explanatory text. 
 
 PUBLISHED BY 
 
 OWEN B. MAGrNNIS, NEW YORK. 
 1896. 
 
Copyrighted, 1896, 
 
 BY 
 OWEN B. MAGINNIS. 
 
 
CONTENTS 
 
 CHAPTER I. 
 
 CHAPTER II. 
 CHAPTER III. 
 CHAPTER IY. 
 CHAPTER V. 
 CHAPTER VI. 
 CHAPTER VII. 
 CHAPTER VIII. 
 CHAPTER IX. 
 
 CHAPTER X. 
 CHAPTER XI. 
 CHAPTER XII. 
 CHAPTER XIII. 
 CHAPTER XIV. 
 CHAPTER XV. 
 CHAPTER XVI. 
 CHAPTER XVII. 
 CHAPTER XVIIF. 
 CHAPTER XIX. 
 
 THE PRINCIPLE OF THE ROOF AND GENERAL DIREC- 
 TIONS. 
 
 LAYING OUT AND FRAMING A SIMPLE ROOF. 
 HIP AND VALLEY ROOFS. 
 ROOFS OF IRREGULAR PLAN, 
 SQUARE PYRAMIDAL ROOFS. 
 To FRAME A PENTAGONAL ROOF. 
 HEXAGONAL PYRAMIDAL ROOFS. 
 CONICAL ROOFS. 
 
 To FRAME A CONICAL ROOF INTERSECTED BY A PITCHED 
 ROOF. 
 
 OCTAGONAL ROOFS. 
 
 FRAMING AN OCTAGONAL ROOF OF GOTHIC SECTION. 
 
 FRAMING AN OCTAGONAL MOLDED ROOF. 
 
 FRAMING AN OCTAGONAL ROOF WITH CIRCULAR DOME. 
 
 To FRAME A HIGH-PITCHED OR CHURCH ROOF. 
 
 To FRAME A MANSARD ROOF. 
 
 HEMISPHERICAL DOMES. 
 
 To FRAME A CIRCULAR ELLIPTIC DOME. 
 
 To FRAME AN ELLIPTIC DOME WITH AN ELLIPTIC PLAN. 
 
 To FRAME A CIRCULAR. MOLDED ROOF. 
 
CHAPTER XX. To FRAME A GOTHIC SQUARE EOOF OF 4 CENTRE SEC- 
 TION. 
 
 CHAPTER XXT. To FRAME A TRUSSED EOOF OF MODERATE SPAN ON IHE 
 BALLOON PRINCIPLE. 
 
 CHAPTER XXII. To FRAME A ROOF OF UNEQUAL HEIGHTS OF PITCHES 
 AND PLATES. 
 
 CHAPTER XXIII. To FRAME A HIP AND VALLEY EOOF OF UNEQUAL PITCH. 
 
 CHAPTER XXIY. To FRAME A EOOF OF UNEQUAL LENGTHS OF EAFTERS. 
 
 CHAPTER XXY. To FRAME A EOOF WITH PITCHED RIDGES. 
 
 CHAPTER XXVI. To FRAME A ROUND-HOUSE EOOF. 
 
 CHAPTER XXVII. FRAMING CANTILEVER EOOFS. 
 
PREFACE. 
 
 IX placing this little work before the student of Architecture or Build- 
 ing Construction, I would state that it is not intended for those 
 uneducated but for those who, desirous of becoming proficient in the 
 higher principles of construction, wish to study and apply the best 
 methods in actual daily practice. With the assurance to the student, 
 that he will find the contents, i studied, will return him full remuneration 
 by his becoming more valuable on account of his increased knowledge, I 
 send it forth confidently. Tiie cardboard models will prove the accuracy 
 of the methods described. The articles being originally published in 
 Tke Carpenter, are now issued edited and revised. 
 
 The entire work is dedicated to my wife, by whose aid and encour- 
 agement I have been enabled to persevere and succeed in technical 
 principles. 
 
 THE AUTHOR. 
 YORK CITY, 1896. 
 
ROOF FRAMING MADE EASY 
 
 CHAPTER I. 
 
 THE PRINCIPLE OF THE ROOF AND GEN- 
 ERAL DIRECTIONS. 
 WITH a view of explaining the 
 principle of the truss and its 
 practical application in the con- 
 struction of roofs and bridges, 
 I have commenced with this chapter. 
 Let A B and A C be two rafters rest- 
 ing together at the ridge or point, as A. 
 Even by their own weight, these two 
 rafters would have a tendency to slip at 
 the points B and C, and to sink at A. 
 If a tie rod or beam be stretched from 
 B to C, and the rafters, A B and B C, 
 be made stiff or rigid, and the tie, B C, 
 not liable to stretch, then A will be 
 made a fixed point. This is the ordinary 
 roof of two rafters in which the tie, B C, 
 is the attic floor beams, and which form 
 may be used for houses of small span. 
 
 FIG. 1. 
 
 When the span is wide, so wide in fact 
 that the tie, B C, being unsupported in 
 the centre, tends to sag by reason of its 
 length, then the conditions of stability 
 are injured. Now if from the point or 
 peak A a string or tie be let down and 
 attached to the middle of B C, as D, it 
 will then be impossible for B C to bend 
 or sag down, as long as A B and B C are 
 the same length . D will be also like a 
 stationary point if the suspension on tie 
 A D be of iron or wood and not stretch. 
 But the span may be increased, 01 the 
 size of the rafters A B and A C dimin- 
 ished until the rafters tend to sag, and 
 to prevent this, "struts," as D E and D 
 F, are set in, reaching from the station- 
 ary point D to the middle of each rafter, 
 or" to the centre of its length, as E and 
 
 F; thus making E and F stationary 
 points, provided the struts E D and F D 
 remain their full length . 
 
 By this means the "truss" or tie up, 
 the point D, and the frame, A B D C, is 
 a trussed frame, or in the term applied 
 in carpentry, a "truss." Similarly, if 
 D C be long its centre can be suspended 
 from the fixed point E by a suspension 
 rod, as E G. 
 
 FIG. 2. 
 
 In every truss there are two principal 
 strains exerted on the pieces. These are 
 termed Compression and Tension. For 
 this simple truss the rafters A B and A 
 C are in Compression, or being pushed 
 together. A D and B C are extended, 
 or in Tension. Those which, are in ten- 
 sion can either be made of wood (as 
 wood is very little liable to stretch) or 
 of wrought iron rods, but never of ropes, 
 or any material likely to stretch. 
 
 From the above, the student will un- 
 derstand that: the rafters, by their not 
 being subject to compression or crush- 
 ing, and the tie rod or beam, not being 
 liable to stretch, or, in better words, sub- 
 ject to tension, and the suspension rod 
 complete the truss, thus preventing the 
 sagging of the centre of the tie beam. 
 
 In modern roof construction, en- 
 gineers, as a rule, use timber for rafters 
 and struts and iron for tie and suspen- 
 sion rods; these materials being light 
 and easily put together ; and I am sure 
 many readers will meet roofs of this 
 class. 
 
 In the ordinary form of house roof 
 shown at Fig. 2, the rafters are in com- 
 pression, the ties, or attic floor beams. 
 
8 
 
 ROOF FRAMING MADE EASY. 
 
 in tension, and the col- 
 lar beam is in compres- 
 sion, as it takes the place 
 of the struts, yet gives 
 the head room. 
 
 GENERAL DIRECTIONS. 
 
 Roofs should be laid 
 out to a scale on a large 
 sheet of detail paper 
 or on a drawing-board, 
 using a lead pencil and 
 two-foot rule or steel 
 square. The writer gen- 
 erally uses either 3 inch 
 or 1^ inch scale ; if pos- 
 sible, as it sometimes is 
 on small work, full size . 
 
 The reason these are 
 the best working scales 
 is because the three inch 
 scale works as follows : 
 
 3 inches = 1 foot 
 
 H 
 i 
 
 ir 
 
 i 
 
 = 6 inches 
 
 = 4 
 = 2 
 = 1 
 k 
 - t 
 
 The one and a half 
 inch scale is similar but 
 the divisions are not so 
 handy. For instance: 
 1-| inches = 1 foot 
 f 4i =6 inches 
 i " = 4 
 i ' =2 
 
 I :: i 1 ! 
 
 The above two scales 
 are the best working 
 scales with the excep- 
 tion of the half size 
 proposition which is veiy 
 simple and easily applied 
 thus : 
 
 6 inches = 1 
 
 5 " =10 
 
 4 = 8 
 
 3 
 
 2 
 
 foot 
 inches 
 
 1 
 
 = 6 
 
 = 4 
 
 = 2 
 
 = 1 
 
 1 ^ t i 
 
 Tff o 
 
 1 < < 1 
 
 T2 7* 
 
 The foregoing scales 
 are the best for mechan- 
 ics, either foremen or at 
 the works. The full 
 size laying out is best 
 
 H 
 
 FIG. 3 PLAN OF RAFTERS. 
 
 FIG. 4 PLAN AND LAYOUT OF A SIMPLE ROOF. 
 
ROOF FRAMING MADE EASY. 
 
 when possible. Whether the work is 
 laid out to scale or full size, the exact 
 measurements should always be marked 
 in plain figures on every piece. 
 
 The figures on the steel square for 
 marking cuts may be used if desired, 
 by placing the square on the scale draw- 
 ing and noting the figures on the blade 
 and tongue. 
 
 CHAPTER II. 
 
 LAYING OUT AND FRAMING A SIMPLE 
 ROOF. 
 
 J ET A, B, C. D, Fig. 3, be the plan 
 
 Lof the wall plates. A D a gabled 
 end. and B C a hipped end of the 
 building. The roof is 12 feet wide 
 
 inch rafter as shown on the top of Fig. 
 3, deduct half the thickness of the ridge, 
 half inch, from each rafter peak, cut 
 also notch out for the cut on the plate . 
 All the rafters from F to E will be 
 framed thus: 
 
 For the hip rafters, take the distance 
 B* C. and transfer it to J. K, divide it 
 into two parts 6 feet at L. and square up 
 as L. M, O. Join M, J, and M ? K. Pro- 
 duce J, M, to N, (dotted line) and join 
 N, K. N, K, will be the centre line 
 length of the hip, and the width may 
 now be set off on each side of it in the 
 manner shown in the diagram. 
 
 With K as centre and K, N as radius, 
 strike the arc N. O. cutting L, M ex- 
 tended in O. On L, K lay off the jack 
 rafters as Q. P, S, R, etc. ; equally spaced 
 
 FIG. 5. 
 
 to the outside faces of the wall, and the 
 rise or pitch 4 feet or one-third the span. 
 The dotted lines denote centre lines. 
 
 To lay out the gable end produce the 
 center line of the ridge E, I. F to G, and 
 from F measure up 4 feet, join G, A and 
 G, D. Now set off on each side of the 
 dotted line shown, the width of the 
 rafter 2 inches on each side for a 4 inch 
 rafter, and 3 inches on each side for a 6 
 
 and square to the wall plate. The 
 exact lengths of the jacks will be to 
 the line O, P, R. K, and their side bevel 
 will be as P. The bottom notch will of 
 course be as at A or D ; K shows the 
 bottom notch for the hip rafters and N 
 the peak cut or plumb cut. Great care 
 should be taken to have the lines as 
 accurate as possible, so measurements 
 will be exact. 
 
10 
 
 ROOF FRAMING MADE EASY. 
 
 CHAPTER III. 
 HIP AND VALLEY ROOFS. 
 
 THE next roof which I produce is 
 one of the hip and valley class, or 
 a main rectangular building, with 
 an L or addition. A, B, C, F, D, 
 is the plan of the building and the out- 
 side line of the wall plates. The roof is 
 of half pitch or square pitch as some 
 mechanics call it, which means that the 
 height of the roof is equal to half the 
 width of the house. The house has two 
 gables, one on each end of the main 
 part with a hip on the L, and the inter- 
 section of the L roof with the main roof 
 produces two valleys. E, I, D, is the 
 plan of the hip and E, J, D, is the eleva- 
 tion of it shown on the elevation Fig. 6, 
 where the general view of the con- 
 structed roof is shown. Q, J, and J, F, 
 are the valleys on the plan. 
 
 FIG. 6. 
 
 In framing this roof the simplest way 
 is as follows : 
 
 To obtain lengths and bevels of the 
 common rafter, produce the ridge line 
 G, J, H, to L and K. Join A, K, and 
 K, Q; also B, L, and L, C. A, K, will 
 be the neat length of the common rafter, 
 if no ridge board is inserted ; but if there 
 be a ridge board, half its thickness must 
 be sawn off the length on the bevel . K 
 is the bevel for the top or peak cut and 
 A, the bevel for the cut on the plate. 
 Any ordinary mind will see the sim- 
 plicity of this method. 
 
 For the hip rafters which will stand 
 over the seats E, I. and D, I, produce 
 the line D, I, to M, and set off on it the 
 height of the pitch I, M, equal to K, G. 
 Join M, E; M, E, will be the exact 
 length of the hip rafter required, and 
 the bevel at M, will fit the top cut, and 
 that at E, the plate cut. In regard to 
 the cuts for the jack rafters, which run 
 up the hips and valleys, it might be said 
 that the top cuts against -the ridges for 
 the rafters which run up' the valleys 
 have the top cut the sameKas the com- 
 
 mon rafter top cut. The bottom one 
 which nails against, can be readily de- 
 termined by the following simple 
 method: Produce the ridge line J, I, to 
 N, and make D, N, and N, E, equal to 
 M, E, the length of the hip, W, is the 
 jack on its seat or as it will appear in 
 position. X, is the exact length of it 
 from the plate line to the hip, and the 
 bevel at X, will be the exact bevel for 
 all jacks both on hips and valleys, being 
 reversed for different sides, right and 
 left hand. 
 
 The plumb cut of the jacks will be half 
 pitch, or on the steel square, 12 and 12. 
 
 In order to prove the exactness of this 
 method of laying out such a roof, we 
 will proceed to develop its planes or 
 sides. 
 
 As to the rectangular plane, A, B, G, 
 H, take a pair of compasses with a pen- 
 cil point, and with A, as centre, and 
 with A, K, radius, describe the arc K, 
 I; draw I, U, parellel to A, B, produce 
 G, A, to I. and H, B, to U, this will give 
 
 A, B, U, I, the exact covering of A, G r 
 H, B, on the pitch C, K; A, K, being 
 the length of the common rafter with 
 its necessary bevels. 
 
 For the plane J, H, C, F, produce B, 
 L to G', and draw C, F, Q, parallel to- 
 
 B, L, J. G'. Make L. J, G', equal to H, 
 J, G. C, F, equal to C, F, also F', Q\ 
 equal to Q, F, make J, F, and J, Q, 
 equal to M, E, which will complete the 
 plane and surface to cover G, J, H, C, 
 F. Q, on the plan. 
 
 For the plane J, F, D, I, take D, as 
 centre, with D, F, radius, and describe 
 the quarter circle F, P. Produce E, D, 
 to P, and through P draw P, O, parallel 
 to D, N, also through N draw N, O, 
 parallel to D, P. D, N, O, P, will be 
 the developed covering, and Q, R. S,. 
 E, is similarly found. 
 
 B, L, C, and A, K, Q, are the gables. 
 
 Now if this roof be laid out on a piece 
 of thin wood or stiff Bristol board the 
 roof can be folded over by cutting en- 
 tirely through the following lines: Cut 
 from K to A. A to I, I to U, U to B, B 
 to L, L to G', Q' to J', J' to F', F to C, C 
 to F, F to D, D to P, P to O. O to N. N to- 
 E, E to S, S to R, and R to Q. Also 
 make a slit half way through the thick- 
 ness of the board, from Q to A. A to B, 
 B to C. C to L, D to N, D to E, and E to 
 Q. By folding the sides or planes over, 
 the exact roof will be seen, thereby prov- 
 ing the method. 
 
 The many apparently complex roofs 
 which are nowadays placed on frame 
 buildings are apt to discourage those 
 young mechanics who are ambitious, so 
 in order to simplify and bring them 
 within the grasp of all I have now 
 
ROOF FRAMING MADE EASY 
 
 UNIVERSITY 
 
 11 
 
 adopted a plan of roof of somewhat un- 
 usual form. 
 
 At Fig. 7 the plan isABCDEFG 
 H I J L and K, being the plan of a small 
 frame house costing about $2,000. Fig. 
 8 is an end view or gable elevation show- 
 ing the pitch is of the common rafters 
 which we will assume to be full pitch, 
 or 12 inches rise and 12 
 inches run on the steel 
 square. A B is the top 
 line of the plate across the 
 bay, or across the widest 
 
 rrt of the house. A K 
 the span across the 
 main walls and E J the 
 rise or pitch; therefore 
 A J will be the length 
 of the common rafters 
 on the plan Fig 7, that 
 will be set on the plate A 
 K from N to O on the 
 ridge. A G, Fig. 8, is the 
 span across the narrowest 
 part of the house or from 
 A to B. Fig. 7, and E M 
 is the rise or pitch, con- 
 sequently A M will be 
 the length of the short 
 common rafters and the 
 bevels will be as repre- 
 sented at J M and A. 
 
 Now to find the lengths 
 of the hips and valleys 
 and bay window rafters, 
 refer to Fig. 7, and com- 
 mencing at the near val- 
 ley C M square up the 
 line M R, make it equal 
 to E M on Fig. 7 and join 
 C R. OR will be the 
 length of the valley with 
 top and bottom bevels as 
 shown. On the seat of 
 the hips X D, square up 
 the rise N T equal to E J, 
 Fig. 7, and join D T for 
 length of hip, with top 
 and plate bevels as at D 
 and T. It will be noticed 
 that these rafters are 
 parallel on the* lay-out 
 because their seats are 
 parallel, therefore they 
 must be correct ; the val- 
 ley rafter L Q to stand 
 over L P is determined in 
 like manner also the hip 
 S K to stand over O K. 
 
 As I have previously shown several 
 ways to obtain the lengths of jack raft- 
 ers on half pitch roofs I will not repeat 
 this simple method here but go on and 
 give layout of bay window timbers 
 
 Referring again to the engraving Fig. 
 8 we find that the plate line of the bay 
 
 C H D is higher or raised up 4 feet above, 
 the level of the plate line of the princi- 
 pal or main walls as A G B; to find 
 lengths of rafters we go back again to 
 Fig. 7 . Here on the seat of the hip E U 
 we proceed to square up the rise U V 
 and join E V, which will be the length 
 of the hip U V, being equal to the rise 
 
 FIG. 7 PLAN AND LAYOUT OF ROOF. 
 
 C J, Fig. 8. There will be four hips 
 this length to stand over E U, F U, G 
 U, and H U, on the seat of the W X. 
 Square up the rise X Y and join W Y 
 for length of valley. There will be two 
 needed, one for each side. Jacks can 
 be found as before described. Regard- 
 
ROOF FRAMIiNG MADE EASY. 
 
 ing the jack rafters reaching from the 
 valleys over W X to the hips D N and 
 O P, I might state that the bottom and 
 top cuts will be alike up to the points N 
 and O where the hips join the ridge N 
 O. Against it they will be a square 
 cut on top edge with the down cut as at 
 J Fig. 7. 
 
 A 
 
 FIG. 8 PROJECTION OF ROOF. 
 
 When calculating the timbers or lay- 
 ing out roofs of this description, too 
 much care cannot be bestowed in watch- 
 ing the exact number of rafters required, 
 the right and left hand cuts of the bevels 
 on the jacks, etc., and the exactitude of 
 framing to the neat lengths required so 
 as to prevent mistakes or recutting. 
 
 do this I will not illustrate it here.) 
 This process will give the seats of the 
 hips as shown and lettered, with the 
 ahdition of a short piece of ridge F, G. 
 To find the lengths and bevels of the 
 rafters, proceed as follows: For the 
 common rafters to range from U, E, to 
 V, F, on the one side, and from E, W, 
 to G, X, on the other side ; 
 raise up the pitch G, P. 
 Square put from G to X, 
 and join P, X which 
 joining line will be the 
 exact length of the com- 
 mon rafter from outer 
 edge of plate to centre 
 line of ridge. To obtain 
 length of hip rafters 
 square up from each point 
 at the peaks, as E, H ; F, 
 I. on one side. Make E, 
 H, and F, I, each equal to 
 G, P; A, H, and B, I, will 
 be the lengths of the 
 hip rafters, which will 
 E, and B, F. The hip 
 will be set up over the 
 
 CHAPTER IV. 
 
 ROOFS OF IRREGULAR PLAN. 
 
 THIS chapter embraces a roof of an- 
 other and ratheruncjommonplan, 
 and one which will be interesting 
 to work out. It is a form of roof 
 which sometimes occurs and will prove 
 useful. 
 
 A, B, C, D, Fig. 9, is the plan, and it 
 will be noticed that the side walls are 
 not parallel, or at equal distance apart 
 from end to end, but spread or widen 
 out from A to B, and from C to D, or B, 
 
 D, is longer than A, C. Similarly A, B, 
 is longer than C, D, and not parallel to 
 C, D. For this reason coupled with the 
 necessity of keeping the ridge level on 
 both sides a deck is formed on the top, 
 or more properly two ridges are needed, 
 one for each side, and parallel to each 
 wall plate; these are shown as E, F, and 
 
 E, G. 
 
 The seats of the hips as A, E, C, E, B, 
 
 F, and D, G, are found by bisecting each 
 of the separate angles on the plan, 
 which can be done by taking any two 
 points equidistant from the apex of the 
 angle as A. and striking intersecting 
 arcs. (As every student knows how to 
 
 rise over A 
 rafters which 
 
 seats, C, E, and D, G, are determined in 
 a similar manner. The top and bottom 
 bevels delineated at the peaks and bot- 
 toms are the top and bottom cuts of each, 
 and it will be noticed that no two bevels 
 are alike, so that each rafter must be 
 carefully laid out and marked for each 
 particular corner. There will be four 
 hips of different lengths and with differ - 
 erent bevels, so they must be properly 
 framed. In regard to the jack rafters 
 they are shown on the right side spaced 
 out on the wall plate from X to D, 
 against the hip, G, D. Their top 
 down bevel or plumb cut will be the 
 same as that at P, and that at R will be 
 the side bevel. Similarly with those 
 from D to M, the plumb cut will be the 
 same as P, but the bevel will be that at 
 O. 
 
 In order to develop the planes of this 
 roof, commence by drawing E. U, S, 
 from E, through W, at right angles to 
 E, F, or A, B; also draw F, V, T, par- 
 allel to E, U, S. Make A, S, equal to 
 A, H, by taking A as center with radius 
 A. H, and striking the arc H, S. 
 Through S, draw S, T, parallel to A, B. 
 If a center be taken at B, and an arc 
 struck as I. T, N, it will be found that 
 the arc will pass through T. or F, V. 
 produced at T. The surface A, S, T, B, 
 will cover the plan. A, E, F, B. on the 
 pitch E, H. 
 
 Draw E, J. square to A, C, and pro- 
 duce to K. Sweep H, S, to K, and join 
 A, K, and K, C. A, K. C, will be the 
 covering plane which will cover over A, 
 E, C, on plan. For the plane of A, E, G, 
 
ROOF FRAMING MADE EASY. 
 
 FIG. 9. 
 
 D, draw E, W, square to E, G, and pro- 
 duce to Q. With C as centre and C, K, 
 as radius, strike the arc K. Q; draw Q. 
 R, parallel to C, D. Join C, Q, which 
 will be the centre of the hip rafter on 
 this side. Draw G, X, square to C. D, 
 and produce to R> join R, D, C;Q, R, D. 
 will be the covering plane which will 
 cover over C, E, G, D, on the pitch 
 G, P. 
 
 Now draw G, M, and F, L, square to 
 B, D, and produce them to N and O. 
 
 A model can be made of this roof by 
 cutting out the entire outside line of the 
 covering and making a slit from A to B, 
 from B to D, from D to C, from C to A , 
 also from Q to R, which being folded up 
 will show the completed roof with the 
 rafters, cuts and bevels in position . 
 
 FIG. 10. 
 
 With D, as centre and D, R, as radius 
 describe the arc R, O, also the T. N. 
 Join N. O, B; N, O, D, will be the cov- 
 ering of the plan B, F. G, D, on the 
 pitch G, P. Q, R, Y, Z, will be the 
 covering or deck, being the same size or 
 area as E, F, G. 
 
 At Fig. 10 will be seen the elevation, 
 or as it will appear when framed, raised 
 and covered. 
 
 CHAPTER V. 
 
 SQUARE PYRAMIDAL ROOFS. 
 
 DOOF framing is a study well worthy 
 the attention of every student of 
 J[ V building construction. The roof 
 illustrated and described in this 
 chapter is one which occurs on many 
 cottages and houses now-a-days. It is 
 one of a kind of tower roofs on a square 
 plan or as they are sometimes termed 
 "Pyramidal roofs." A, C, D, F, Fig. 
 11, is the projection of the roof com- 
 pleted. A, C, D, B, Fig. 12, the plan cf 
 the roof on the plates; AE, CE. DE and 
 BE, being the hips which form the 
 shape of the roof or seats over AF, CF, 
 DF, on Fig. 11, stand. The fourth hip 
 over BE, cannot be seen on the projec- 
 tion, Fig. 11 . 
 
 In order to find the length of the hipp, 
 produce the line E, B. indefinitely. 
 Now set off, measuring from E, the 
 height of the peak to F, Fig. 11. Join 
 
ROOF FRAMING MADE EASY, 
 
 FIG. 11. 
 
 AF, Fig. 12, which will be the exact 
 length of either of the four hips. In 
 framing this roof it is best to let two op- 
 
 posite hips as BE, and EC, on the same 
 line abut against each other at the peak, 
 and to cut off their thickness from the 
 other two top or peak cuts, thus : If BE, 
 and EC, be each 2 inches thick then 1 
 inch will be cut off the peak cuts of AE, 
 and DE which rest against them at E. 
 This is done in the same manner, as 
 every top cut of a rafter resting against 
 a ridge must have half the thickness of 
 the ridge cut from each rafter. The 
 bevel at F, Fig. 12, is the bevel of all 
 four top cuts and that at A, the bevel 
 for the cuts on the plate. 
 
 Concerning the jack rafters, the best 
 way to determine their length is to set 
 them off the plate as from A to C. Fig. 
 12, then to draw a line as H, E, G, 
 through E, parallel to AC, or BD. With 
 A, as centre and AF, as radius describe 
 the arc FG, cutting the H, E, G, at G. 
 Join G, A, and G, B. The triangle, or 
 more properly speaking, the triangular 
 surface G, A, B, will be the exact 
 covering surface of the roof plane 
 A, E, B. 
 
ROOF FRAMING MADE EASY. 
 
 15 
 
 From where the jack rafters come 
 against the hip AE, draw lines parallel 
 to E, G, and square to A, B, cutting A 
 G. as shown. The lines reaching from 
 the plan line A, B, to A, G, will be the 
 exact jack rafters and the bevel at K, 
 will be the side cut against the hip, with 
 the bevel at F, as the vertical cut, and 
 that at K, the bottom or pla+e cut. 
 
 The development of the covering for 
 the remaining three planes of the roof is 
 found by drawing the line I, J, 
 through E, parallel to A, B, or C, D; 
 then with B, as centre and B, G, as 
 radius intersecting E, J at J, and joining 
 J, B and J, D ; a similar process can be 
 gone through to determine the points 
 H, and I. thus obtaining the four con- 
 vexing planes. 
 
 To prove the accuracy of this and the 
 two previous roof problems before de- 
 scribed, or in fact any roof problem, the 
 plan should invariably be 
 laid out to a scale, say H 
 inches to 1 foot. On a sheet 
 of cardboard ^ inch scale 
 will do if the roof be very 
 large, then to make a card- . 
 
 board model. Here this can ' 
 
 be done and when the lines 
 have been laid down, as ju&t J[j 
 described, the entire model 
 may be made as follows: 
 With a sharp pocketknife 
 cut clean through the card- \ 
 board from A to G, from G to 
 
 B, from B to J, from J to 
 D, from D to H, from H to 
 
 C, from G to I. and from I 
 to A. Next make a slit 
 halfway through the card- 
 board from A to B, from B 
 to D, from D to C. and from 
 C to A. Proceed to fold the 
 
 planes over the seats till they all join at 
 the edges, thereby making a completed 
 cardboard roof resembling Fig. 11 with 
 the jacks and bevels in position, and 
 with all the cuts fitting as they ought to. 
 
 houses built on this plan, I think it wise 
 to describe it as the knowledge is easily 
 carried and may prove useful . 
 
 Fig. 13 illustrates the simplest and 
 most accurate method of. striking out a 
 pentagon, or five-sided figure, one side 
 being given. For example, if the length 
 of one plate line as E D, Fig. 14, be 
 drawn to a scale on any plan, the car- 
 penter can very readily lay out his 
 pentagon full size or half size, as fol- 
 lows: Let C E, Fig. 13, be any line 
 equal to the line E D, Fig. 14. Divide 
 C E, into two parts at G, and produce 
 C G E. Make E J, equal to C E. and 
 with E, as centre and radius E C, de- 
 scribe the semi circle C K L F J. Di- 
 vide tho semi-circle into five equal 
 parts at the points K L F and M. From 
 the point G, square up the line G I. 
 Join E and F, and bisect the joining 
 line E F, at H . From H, square out, 
 
 A 
 
 CHAPTER VI. 
 
 To FRAME A PENTAGONAL ROOF. 
 
 SOME time since the writer was re- 
 -quired to lay out a pentagonal or 
 five-sided band stand which had a 
 slate roof terminating in a wooden 
 finial at the apex. As this roof is of a 
 form rarely met with in building con- 
 struction, I introduce it here, being 
 under the impression that readers 
 might perhaps have occasion to use 
 the lines for such a roof. However, as 
 there are pavilions, pagodas or summer 
 
 l<*~ (S \ 
 
 JL ~'~ & 
 
 13 
 
 FIG. 13. 
 
 cutting the line G I, at I, and with I as 
 centre and F as radius, describe the cir- 
 cle A B C D E F. Set the compasses or 
 a rod to the length C E, or E F, and 
 space off round the circle, also join the 
 points together by lines and complete 
 the pentagon, as indicated by the heavy 
 black lines . 
 
 In order to lay out the hip and jack 
 rafters for a roof of this description, 
 proceed to Fig. 14, and lay out the out- 
 side lines of the plates as A B, B C, C D, 
 and D E, also with the compasses, de- 
 scribe the thickness of the finial or boss, 
 against which the top ends of the five 
 hip rafters rest, also lay out the hip 
 rafters as indicated in the diagram in 
 three lines; the centre one being the 
 line of the backing, and those oh either 
 side the thickness of ths hip . By back- 
 ing is meant beveling the top edges of 
 the hip to permit the roof-boards or 
 
16 
 
 ROOF FRAMING MADE EASY. 
 
 sheathing to lie on the solid timber in- 
 stead of only on the sharp arris or edge 
 of the rafter. The seats of the jack 
 
 centre or apex and B. Fig. 14. Square 
 up from the apex as X, equal in height 
 to the pitch or rise of the roof. Join B 
 
 FIG. 14. 
 
 rafters may also be laid down as shown. 
 To find length of hip rafters join the 
 
 FIG. 15. 
 
 and X, to obtain the length of the hip 
 and its apex and plate cuts, seen in tho 
 diagram. There will, of course, 
 be five hip rafters this length 
 required. The length of each 
 jack rafter may be obtained in a 
 very simple way by squaring up 
 from each jack where each rests 
 against the hip and setting off 
 each height of each jack, thus 
 determining the exact length of B 
 Z C, being the development of the 
 B R C. The side bevel will be as 
 Q, which must be reversed for 
 jack on opposite sides of the hips. 
 There will be five sets with a 
 right-hand side bevel and five 
 sets with a left-hand side bevel. 
 Regarding the 'backing of the 
 five hip rafters, the first thing to 
 be done is to find the desired 
 bevel. This is easily accom 
 
ROOF FRAMING MADE EASY. 
 
 17 
 
 plished by taking any point, as S, Fig. 
 15. and from S, drawing square to E R, 
 as O P. From S. let fall a line per- 
 pendicular to E V, as S T. With S 
 as centre and S T as radius, describe the 
 circle S T U cutting R E, at U. Join 
 U P and U 9. O U P, will be the bevel 
 of the backing and a bevel may be set 
 to one side of the rafter . 
 
 CHAPTER VII. 
 
 HEXAGONAL PYRAMIDAL ROOFS. 
 
 READERS will see at Fig. 16 the 
 top and side views of a hexagonal 
 or six-sided roof, or one which 
 has a wall plate running round 
 on six walls as shown above, the dotted 
 lines representing the angle lines of 
 the hexagonal figure. The completed 
 roof with the boarding or tin on will 
 appear as shown on lower sketch. 
 
 In order to frame this roof the follow- 
 ing system should be used : 
 
 At* Fig. 16 proceed to lay out on a 
 board or paper to a scale of 1 or 3 
 inches to the foot, the plan of the wall 
 plates (on the outside line) . *A, B, C. 
 1). E, F ; and join the points of the in- 
 tersections of the sides, as A D, B E, and 
 C F ; passing through the centre G. 
 This gives the seats of the hip rafters A 
 G, B G, C G. D G, E G and F G ; six in 
 all. To find their exact length, square 
 up from E. G, as G. J. Lay off also to 
 the same scale, the exact height in feet 
 of pitch or rise of the roof from G, to J, 
 and join J, E, which line will be the ex- 
 a'jt length of the hip rafter as seen in 
 the diagram with the top and bottom 
 bevels necessary for the cuts, these be- 
 ing given at once without any uncer- 
 tainty. 
 
 To find the length of the common 
 rafter, to stand over H, G, set off the 
 pitch G. I. on G, C, equal to G, J, and 
 join H, I. for its length. This rafter is 
 rarely used on roofs of this class, ex- 
 cept when they are of large area, as 
 only the jacks are requisite, especially 
 on modern frame houses where they 
 seldom exceed eight feet in width, thus 
 requiring short rafters. 
 
 To develop this roof take a pair of 
 compasses, and with E. as centre, and 
 radius E. J. describe the arc J, M L, 
 Cutting H. G, produced in L. Join E, 
 L, and D, L, which will give the trian- 
 gle E, L, D. the covering over the plan 
 E. G, D, on the pitch or rise G, J. Bi- 
 s ct or rather divide E, F, into two 
 parts at Q. Square up from Q. cutting 
 the arc J. M. L. at M. Join M, E and 
 M, F. The triangle E, M, F.Jwill lie 
 
 over E. G, F. The remaining four tri- 
 angular developments or coverings can 
 be laid out from the foregoing bv 
 making J, O, H, K, R, N, and S, P\ 
 equal in length to Q, M, or a simpler 
 method would be to take G, as centre 
 with G, M. as radius and describe short 
 arcs cutting O, K, N. and P, thus giv- 
 ing the exact lengths at one sweep, and 
 insuring their being alike so as to meet 
 at the centre G when folded. 
 
 I 
 
 FIG. 16. 
 
 The side bevel at K, will make the top 
 cuts on the jack rafters fitting against 
 the hips, the bottom cuts fitting on the 
 plates being the bevel at H. 
 
 Almost every mechanic knows how a 
 hexagon or six-sided figure is struck 
 out, still in case there should be even 
 one student who is at sea in regard to 
 it, I repeat the method of doing so here. 
 The diameter or length from angle to 
 angle is usually given, or if not, is 
 easily found by joining the angles as 
 before described. Now to lay out any 
 
18 
 
 ROOF FRAMING MADE EASY. 
 
 hexagon, draw any line as F, C, and 
 divide it into two equal parts at G. 
 With G, centre and radius G, F, strike 
 the circle A, B, C, D, E, F. Now take 
 a pair of dividers (sharp points on both 
 legs) and from C, with one point on C, 
 space out the six distances C, B, B, H, 
 A, F, F, E, E, D, and D, C. Draw the 
 lines as shown for the outline of the 
 hexagon. 
 
 modern houses, barns, etc. The meth- 
 ods to be followed in this chapter are 
 very simple, so that an ordinary 
 mechanic can easily understand them if 
 he only studies the diagram and text a 
 little. 
 
 Supposing A, B, C, D, E, F, G, H, on 
 Fig. 18 to be the plan or plate line of 
 the roof, and O, L, the pitch or rise, it 
 can be laid out as follows : To be more 
 
 M 
 
 \ 
 
 FIG. 17. 
 
 CHAPTER VIII. 
 
 CONICAL ROOFS. 
 
 HAVING treated the usual forms of 
 roofs embracing the hip and val- 
 ley principles, I will now draw 
 attention to the proper laying 
 out and framing of a roof on a circular 
 tower, as this form occurs very often in 
 
 explicit I will take it for granted that a 
 carpenter has a roof to frame with a 
 plan A, B, etc . , of 6 feet diameter, or 
 6 feet from C to G, and 9 feet rise, or 
 from O to L is 9 feet. Proceed to strike 
 the plan A, B. etc., either full size or to 
 scale. It is always better to lay out full 
 size if a floor or drawing-board can be 
 found big enough to do it, but if not, 
 
ROOF FRAMING MADE EASY. 
 
 19 
 
 half size or a scale of 3 inches or 1^ 
 inches to the foot may be used. 
 
 Having struck the circle, draw centre 
 lines for the rafters A E, B F, C G, and 
 D H, and set off the thickness of the 
 rafters as they show on the plan . Next 
 draw any straight line as J K, the same 
 length as C G; raise up the centre line 
 O L, the height of the pitch, and join L 
 K, which will be the length of the raft- 
 ers to stand over A I, B I, C I, D I, E I, 
 F I, and G I and the top and bottom 
 cuts will be directly given; as at L and 
 J, L M and L N are the rafters I D and 
 
 may be determined by striking out the 
 sweeps shown on the plan, 1 1, 2 2, 3 3, 
 4 4, and 5 5. It will be noticed that this 
 roof will require 8 circular pieces for 
 each row, or 40 sweeps in all . One pat- 
 tern will do for each sweep and the re- 
 maining 8 needed can be marked from 
 each pattern. 
 
 Fig. 19 will convey a better idea of 
 the constructed roof, as this illustration 
 represents each stud, plate, rafter and 
 sweep in its fixed position, with the 
 covering boards nailed on half way 
 round. 
 
 FIG. 18. 
 
 I E placed in position and L O is the 
 rafter E I in position. By referring to 
 Fig. 19 the rafters B I, A I and H I will 
 be seen at the rear of the figure. 
 
 If the roof is t.c be boarded vertically, 
 horizontal strips or sweeps will require 
 to be sawn out and nailed in, in the man- 
 ner represented in both Figs. 18 and 19. 
 To do this properly, divide the height 
 from O to L in Fig. 18 and draw the lines 
 representing the sweeps as 1 1 , 2 2. 3 3, 
 4 4, and 5 5. The neat length, and the 
 cuts to fit against the sides of the rafters 
 
 In order to find the exact shape and 
 levels for the covering boards, a very 
 simple method is used, thus : Take a pair 
 of compasses, or a trammel rod, and 
 with L as centre, and L P as radius, de- 
 scribe the arcs J P and K Q. Join L P 
 and L Q, now divide the half circle A, 
 B, C, D, E, into 12 equal spaces on J. P, 
 with a pair of compasses, and join the 
 division marks on J P with L This 
 will give 12 tapering boards and the 
 bevel at X on the plan will be the bevel 
 of the jointed edges. As twelve boards 
 
FIG. 19 
 
ROOF FRAMING MADE EASY. 
 
 21 
 
 will be needed for half the plan, twenty- 
 four will have to be cut out for the 
 other half, so it will be seen that if the 
 sweep or arc J P goes round from A B 
 to E, the sweep K Q will go round H, 
 K, G, etc., to E. The diminishing lines 
 from the point L to the line J P are the 
 inside lines of the joints of the boards 
 shown also in Fig. 19. 
 
 In order to prove the rectitude of the 
 foregoing, a model can be made by 
 drawing the roof to scale on cardboard, 
 and then cutting out the figures from L 
 to J, from J to K, and from K to L. 
 Also cut out the figures L P S, and L Q 
 K. Now if L S K be stood up over A, 
 E, B, F, etc., it will be seen to fit over 
 each. 
 
 In a similar way the figure L J P will 
 bend around ABODE with the peak L 
 over the point I and the line J P around 
 ABODE. In a like manner K Q will 
 bend around A H G F E and L will lie 
 over I, thus proving the correctness of 
 the methods followed. Care must be 
 taken to allow for the intervening raft- 
 ers when framing the peak cuts of the 
 rafters. 
 
 To find the lengths of jack rafters, 
 proceed to Fig. 21 , and lay out the ridge 
 and valley rafter as before. With F as 
 
 To 
 
 CHAPTER IX. 
 
 FRAME A CONICAL ROOF INTER- 
 SECTED BY A PITCHED ROOF. 
 
 AS this is a roof which occurs in 
 many cases, especially in railroad 
 work, it will be found both inter- 
 esting and useful. 
 
 Let A E F B V, Fig. 20, be the plan 
 or wall plate of the conical dome, and 
 A D B, the diameter, also D 0, the rise 
 or pitch. Join A C, to obtain the 
 lengths of the common rafters which 
 will radiate from the centre C, round 
 the circular plate A E F B V, with the 
 top and bottom bevels as represented at 
 C and A. 
 
 On account of the pitched roof C H F, 
 the gable end of which is G I H, with 
 pitch J I, equal in height to D C, inter- 
 secting or cutting into the conical dome, 
 there will be a valley rafter. The seat 
 of this valley will be D F. because J I, 
 being equal^to C D, the ridge J E, will 
 be the same height as the conical apex 
 or peak D . 
 
 To obtain the length of the valley 
 rafter, square up from D, and with D, 
 as centre and D C, as radius, cut off the 
 length D K, equal to D C. Join F K. 
 F K, will be the length of the valley, 
 and as D B. is equal to D F, and the 
 pitches D C. and D K. are equal, there- 
 fore the valley will be the same length 
 as common rafter. 
 
 *FiG. 21. 
 
 centre, and F K, as radius, describe the 
 curve K Z, cutting the ridge at Z. Join 
 F Z. The lengths of the jacks will be as 
 shown on the left side of the ridge. 
 
 The final process is to determine the 
 shape of the covering or roof boards 
 which are laid horizontally. To do this 
 take C, Fig. 20, as center, and with 
 equal spaces up the common rafter as 
 P Q R S, strike the parallel curves P T, 
 Q U, R V, and S W. The exact length 
 of the boards is found by dividing F B 
 into five equal parts and setting them 
 off on B X. Join C X, to determine the 
 length of all to the apex. A very suc- 
 cessful cardboard model can be made of 
 this roof. 
 
 CHAPTER X. 
 
 OCTAGONAL ROOFS. 
 
 AT Fig. 22, A B C D E F G H is the 
 plan of the octagonal roof. I is 
 the centre or peak. A I, B I, 
 etc. , are the seats of the hips. L J 
 is the length of the common rafters. B 
 K the exact length of the hip rafters . 
 
 To find side bevel of hips, produce N 
 I to M, and make B M equal to B K ; 
 join M B and M A. The bevel at M will 
 be the side bevel across the top edges of 
 the rafters, and the bevej 
 
ROOF FRAMING MADE EASY. 
 
 FIG. 20 LAYING OUT OF ROOF. 
 
ROOF FRAMING MADE EASY. 
 
 23 
 
 the hips will be the bevel across the top 
 
 edges of the jacks, right and left hand. 
 
 Proceed to Fig. 23, and to obtain side 
 
 bevel of octagon hip rafters, on B D, 
 
 the seat of the hip, raise up the pitch D 
 E. join E B for length of hip. To ob- 
 tain side bevel of jacks, take B as centre 
 and B E as radius, describe arc E F and 
 
 FIG, 23. 
 
 join F and B. Produce line of jacks to 
 meet B F, and the bevel at G is the side 
 bevel across top of jacks, applied right 
 and left, and on right and left sides of 
 hip. 
 
 CHAPTER XI. 
 
 FRAMING AN OCTAGONAL ROOF 
 GOTHIC SECTION. 
 
 OF 
 
 AS all are interested in unusual 
 problems in carpentry, I have 
 pleasure in laying before them in 
 this chapter one which I solved 
 and which is worth studying out . It was 
 erected on a cupola of a large institu- 
 tion building in thefcity of New York, 
 and is to-day standing complete accord- 
 ing to the architect's design . 
 
 FIG. 24. 
 
 A, B, C, D, E, F, G, H, Fig. 24, was 
 the plan of the cupola or lantern, eight- 
 sided in shape as will be seen, Its ele- 
 vation was as represented in Fig. 25, 
 and its section was a gothic of the 
 equilateral form, as G 6, D 6, Fig. 25, F 
 6, and E 6, were the hip lines of the oc- 
 tagonal plan to stand over on Fig. 24, 
 the seats F 6, and E 6. The radius of 
 the gothic was as shown on the eleva- 
 tion, and from this we will proceed to 
 lay out the roof and and get the curves 
 for the timbers. 
 
 From the points T, U, V, W, X, draw 
 lines square to Q 6', as IL, UM. VN, 
 WI, X. From the space points on the 
 line QZ, make the dotted lines equal in 
 length individually to TL, UM, VN, 
 WI, X; and draw through the points 
 the curve Z, Y, G. Produce NS, and 
 WR to Y and Y', and the lines SY' and 
 RY will denote the curved jack rafters. 
 The bevel at Y, is that which will fit 
 against the side of the hip rafter as the 
 development G, Z, Q, will fold and 
 stand over the G 6', Q. The curve of 
 the jacks will be the same as G 6, Fig. 
 24, and struck from the same radius. 
 This will be readily understood by an 
 
24 
 
 ROOF FRAMING MADE EASY. 
 
 examination of the diagram, Fig. 26. 
 The bevel A 6, Fig. 25, will be the plumb 
 cut of the jack rafters. 
 
 Also, draw level lines from the points 1, 
 2, 3, 4, 5, on 6', 6, cutting the plumb 
 lines from G', 6', at the points 1', 2', 3', 
 4', 5', 6'. Draw the curve G 1, etc.. 
 through these points and this curve will 
 be the exact shape of the hip rafter re- 
 quired to stand over the eight seats seen 
 on Fig. 24. 
 
 For the jacks divide the plate G F. 
 Fig. 26, into six equal parts and draw 
 lines square to the plate for the seats of 
 the jacks, as will be seen from A to H, 
 Fig. 24. These will join with the lines 
 2 U, 4 W, at the points U and W on the 
 line G' 6'. Produce them indefinitely 
 outside G', F'. Now take the divisions 
 G' 7', Fig. 24, and set them off on the 
 line Q Z, Fig. 26, and draw lines square 
 tcQZ. 
 
 FIG. 25. 
 
 In order to find the length and curve 
 of the hip rafters which will stand over 
 the seats on Fig. 24, A 6, B 6, C 6. D 6, 
 E 6, F 6, G 6, H6, proceed as follows 
 Take any octagonal triangle as G 6 F, 
 Fig. 24, and lay it off as G' 6' F', Fig. 
 26, G 6, being a level line. From 6' 
 raise up a plumb line as 6', 6. Next di- 
 vide the gothic sweep on Fig. 24, G 6, 
 into six equal parts, as 1, 2, 3, 4. 5, 6, 
 and carry these over to the centre line 
 6', 6, by horizontal or level lines as indi- 
 cated. Transfer these to 6', 6, Fig. 26. 
 Next divide the line G' 6', into six equal 
 parts, as T, U, V, W, X, and from the 
 points of division raise up plumb lines. 
 
 FIG 26. 
 
ROOF FRAMING MADE EASY. 
 
 CHAPTER XII. 
 
 FRAMING AN OCTAGONAL MOLDED ROOF. 
 
 THE molded roof which I propose to 
 treat in this chapter is one which 
 may not be familiar to readers and 
 may seem difficult to lay out. 
 Various methods have been put forward 
 
 FiG. 27. 
 
 for the purpose of getting the exact 
 cuts, etc., for these roofs, but there have 
 
 been none so far sufficiently intelligible 
 to apply practically. I have, therefore^ 
 worked out one of the most usual forms 
 for the benefit of the trade at large. 
 
 The first roof is a regular "ogee" 
 molded tower roof on an octagonal or 
 eight-sided plan. or. in other words, the 
 plate is eight-sided, as represented at 
 
 ^ ~7 ^ 
 
 7! 
 
 FIG. 28. 
 
 Fig. 29, where the plan of the rafters is 
 denoted, including both hips and jacks. 
 
 Fie. 29 
 
26 
 
 ROOF FRAMING MADE EASY. 
 
 C, D, E, F, G, H, I and J is the eight- 
 sided plate, and eight sides have a 
 molded plane terminating in a point at 
 L, shown in the layout, Fig. 30. 
 
 As there may perhaps be some readers 
 who are not entirely familiar with the 
 proper ways of making an eight-sided 
 figure or octagon, I will explain this 
 here. Let a, b, Fig. 27, be one side of 
 the octagon, say 4 feet long, it is re- 
 quired to construct the full octagon 8 
 feet 6 inches wide. To do this: With 
 the steel square or bevel, draw a-d and 
 
 b-c on a miter, and make each 4 feet 
 long ; then from c and d, draw c, e and 
 d, h, square to a, b. Next from e and 
 h, draw e, f and h, g, op. a miter of 45 
 degrees, and make each 4 feet long; join 
 g and /, to complete the figure. This 
 alone is one way to do it, and a very 
 simple one. Fig. 28 shows another way : 
 Let a d, d c and c & be any square, say 
 8 feet 6 inches wide. Draw the diago- 
 nals from corner to corner, as a c and b 
 d, cutting in e. Now with the com- 
 passes set to e c mark the sides at J and 
 
 FIG. 80. LAYOUT OF ROOF. One-half inch scale. 
 
ROOF FRAMING MADE EASY. 
 
 27 
 
 K, also at h f, etc. Join these points 
 and the eight-sided figure will be given, 
 as shown by the heavy black lines in 
 the engraving. 
 
 By either of the above methods the 
 plate line, C, D, E, F, G, H, I and J of 
 the plan, Fig. 29, may be exactly laid 
 out. or if the cuts or octagon mitres are 
 to be found, the figures 7 and 17 on the 
 steel square will give the cut. The 
 writer prefers, however, to lay out roofs 
 of this character full size, on an ex- 
 temporized floor or drawing-board and 
 to strike out the rafters also full size 
 with a trammel rod, a bradawl and a 
 pencil. K, A, B, L, Fig. 30. is the pro- 
 file of the roof, K A and K B being jack 
 rafters, which will stand over 
 those marked on the plan 
 above ; A corresponding to A 
 above, and B to B above. The * 
 bevel at X. is the side bevel of 
 the jacks fitting against the 
 hips, right and left. The lay- 
 out will explain this very 
 clearly. 
 
 To find the exact shape of 
 the hip curve, as P 10', draw 
 O 10', the seat of one octagon 
 angle or hip rafter, and from 
 O draw O P square from O to 
 10'. See Fig. 30. Divide the 
 "ogee " line L 10 above into 10 
 equal parts with the compasses 
 in the manner shown, com- 
 mencing at L. Draw lines 
 from the dividing points, 
 plumb to the plate or spring 
 line K, O 10. and produce these 
 lines till they cut the hip seat 
 O 10', as P, Q, R, S, T, U, V, 
 W. then from the points where 
 they cut draw lines down, P 1, 
 Q 2. etc. Finally, make the 
 heights of these lines equal 
 to the heights on the regular 
 "ogee" roof above, and trace 
 the curve marked " Outline of 
 Hip" for a pattern rafter, for all 
 the eight hip rafters required. 
 
 As I have laid this roof out to a scale 
 of a half an inch to the foot, students 
 should have no difficulty in reproducing 
 it as shown. 
 
 Readers will find in the sketch, Fig. 31, 
 a very simple method of finding the side 
 cuts of the jack rafters. To square 
 across from the side of the rafter where 
 the thickness of the jacks rest against 
 it as shown here, and to join the oppo- 
 site corners for the bevel as 1-2 and 3-4. 
 Another way to find this cut is to de- 
 velop the roof in the way I have de- 
 scribed in previous chapters. And still 
 another is to apply the steel square on 
 the bottom edge, using the ordinary 
 
 octagon jack rafter cut. The plumb cut 
 being always the same. As the jacks 
 and common rafters have the same pro- 
 file they must coincide. 
 
 CHAPTER XIII. 
 
 FRAMING AX OCTAGONAL ROOF WITH A 
 CIRCULAR DOME. 
 
 AT Fig. 32, let A B C D E F G H, be 
 the plan of the wall plates of the 
 main octagonal roof and H O. 
 G O. G N, E N, F M, E M, E L, D 
 L, DK, CK, CV,BV,BJ, AJ, Aland 
 H I, the seats of the octagonal hip raft- 
 
 FIG. 31. 
 
 ers. The intervening planes between 
 the hips will be circular surfaces as O N. 
 and the rafters, if cut in horizontally as 
 shown in the engraving, will be curved 
 on the outer edge and each sawn to a 
 different radius using the centre of the 
 octagonal plan and upper circular plate 
 J N K L M N U O I. as a fixed centre 
 and increasing the radius for each sweep 
 as they go down on the pitch in the 
 manner seen in Fig. 33, where the sweeps 
 are represented cut in between two hip 
 rafters, the bottom cuts of which rest 
 at the angle of hip; this will also be 
 seen on the plan Fig. 32, as G O and 
 G N. The unoer ends or cuts of the 
 
28 
 
 ROOF FRAMING MADE EASY. 
 
 octagonal hips are cut to, and notched 
 under, the upper circular plate which 
 carries the studding, forming the drum 
 of the dome. 
 
 Concerning the length of the hips, 
 jacks, and common rafters, readers will 
 find the simplest method of determining 
 their length to be that shown on the 
 
 M Q, and join P Q, which will be the 
 length of the common rafter to stand 
 over the seat 3 N. For the jacks from 
 P, on the line P M, set off the distances 
 from the line of the outside of the plate 
 as 1, 2, or 4 and 5 to the point where 
 each comes against the side of the seat 
 of the hips G N, and F N, as P Y, P. W. 
 
 FIG. 32. 
 
 diagram Fig. 32. To obtain the length 
 of the main hips as G N, and so on, lay 
 off the seat F M, and square up from M, 
 as M R. Join R F, which will be the 
 exact length of the hip, to scale, and R, 
 and E, will be the top and bottom bevels. 
 For the common rafter as 3 N, divide F 
 E into two equal parts at P, square up 
 from P as P M, and from M square up as 
 
 From the points W, and Y, square out 
 till each line cuts the line P Q, at X and 
 Z ; P X and P Z, will be the exact length 
 of each jack to the longest point. 
 
 The curved stud for the drum U V, in 
 Fig. 32, shows how the design of the 
 roof may be made more graceful by in- 
 troducing curved studs instead of the 
 straight studs seen in Fig. 33. S T 
 
ROOF FRAMING MADE EASY. 
 
 shows the O G rafters of the top or dome, 
 and with its rise and rim. A' B C on 
 the top side of the engraving illustrates 
 how this roof may be developed in the 
 way I have illustrated and explained in 
 the previous chapters, as I have by slow 
 degrees led up from the simplest to 
 intricate roofs and their framing. 
 
 CHAPTER XIV. 
 
 To FRAME A HIGH PITCHED OR CHURCH 
 ROOF. 
 
 AT Fig. 34 let A. B, C, D, E, F, G. H, 
 I, J, K and L be the plan of the 
 wall plates Around to B will 
 be a circular end. B Y the pitch 
 or length of common rafter which will 
 space along the plate from B to C and 
 from A to L. The bevel at Y will be the 
 
 length which will be found to be the 
 same length as B Y. 
 
 C P, F P, L P and I P are the seats of 
 the valley rafters with the jacks which 
 will fit against all four. I have drawn 
 . these on one side only as the other three 
 are duplicate rafters with the cuts re- 
 versed. The top cut is the same as Y, 
 and the bottom side cut as W, which 
 may be found by developing the roof. 
 Z is the top cut of the valley found by 
 raising up the pitch P Z equal to X Y 
 and joining Z I and Z C, and bevel at C 
 the bottom cut of valleys . 
 
 In order to develop the planes of the 
 roof produce the line C T B to any 
 length. Produce A X B to N and with 
 a pair of compasses strike the arc N Y 
 cutting B N at N, through N draw N U 
 R parallel to C T B and produce S T to 
 
 FIG. 33. 
 
 one required for the top cut against the 
 ridge and that at B the bevel for and on 
 the wall plate. Similar rafters will 
 require to be cut for the semi-circular 
 end and they will be spaced out equally 
 round it as I have drawn them half way 
 round from B to 8. On account of the 
 fitting the top or peak ends of these 
 rafters where they group at the top it is 
 advisable to insert a circular boss or 
 block to fit them against; the half thick- 
 ness of this block must be cut from the 
 ends of the rafters on the plumb cut. 
 This is shown at X in the engraving. 
 The ridge X Y will also require to be 
 fitted to it and the common side rafters 
 A X and B X. S T is the common rafter 
 square to the plate and T U its exact 
 
 U, also draw P through Q to R, and set 
 off the valley and jacks in the manner 
 shown . Next set a pair of dividers to 
 one of the spaces round B 8 and set off 
 the eight equal spaces from B to O, 
 Join NO. If the whole diagram be laid 
 ouf on a sheet of Bristol or cardboard a 
 model may be made and the system 
 proven by cutting entirely the card- 
 board with a penknife or chisel from A 
 to B, thence to O, then to N, N to R. R 
 to P, P to C and so on as before de- 
 scribed. The shape of the covering 
 boards as may be determined by taking 
 Y, as centre and with length YA strik- 
 ing the sweep Y M, then setting off on 
 Y M. 16 spaces each equal in length to 
 1, 2, etc. 
 
30 
 
 ROOF FRAMING MADE EASY. 
 
 FIG. 34 LAYOUT OF A HIGH PITCHED ROOF. 
 
 CHAPTER XV. 
 
 To FRAME A MANSARD ROOF. 
 
 BEFORE commencing to describe 
 the proper methods to follow in 
 framing and raising a Mansard 
 roof. I will first explain what a 
 Mansard roof is. This form of roof de- 
 rived its name from being constantly 
 used by one Francis Mansard, an archi- 
 tect who died in France in the year 1666. 
 He was not, as is generally supposed, its 
 inventor, as the idea had been previous- 
 
 ly adopted by such men as Segallo and 
 Michael Angelo, in Italy. 
 
 The principal reason for the use of the 
 Mansard form is to lessen the excessive 
 height of a roof without resorting to a 
 truss, and to obtain room space in the 
 roof itself. 
 
 To describe or lay out a true Mansard 
 roof, at Fig, 35, let C F, be the true 
 height of the roof equal to half the 
 width on the plate line C B. Draw D E, 
 parallel to A B, and make D F, and F E, 
 equal to A C, and C B. Join A D. pnd 
 E B. Divide D F, and F E, into three 
 equal parts and join A B, and B D. 
 Make F G, equal to d E. and join b G 
 
 D 
 
 FIG. 35 LAYOUT OF A TRUE MANSARD 
 ROOF. 
 
 FIG. 36 LAYOUT OF A MANSARD 
 OR CURB ROOF. 
 
ROOF FRAMING MADE EASY. 
 
 and G D, thus obtaining the true form 
 of the Mansard roof. 
 
 At Fig. 36 another way to describe 
 this roof is shown, and this resembles 
 more the old colonial, or what is called 
 the American curb roof. To describe 
 
 FIG. 37 CROSS SECTION OF ROOF. 
 
 it strike the semi-circle A E D F B, 
 from the centre C, with C D, as radius . 
 Divide the semi circle into 4 equal parts 
 at E D, and F, and join A E, E D, D F, 
 and F B, which will give the proportion- 
 al form of the roof. 
 
 Fig. 38 will give readers a full concep- 
 tion of the framing timbers of a Mansard 
 roof as they will appear when raised. 
 They consist of the usual wall plate and 
 an upper plate which is supported by 
 the flaring or sloping side rafters which 
 
 FIG. 40 To FIND LENGTH OF MANSARD 
 HIP. 
 
 form the Mansard chamber or attic 
 within. Reference to the cross-section, 
 Fig. 37, will make it clearer to the 
 mechanic, as A, is the wall plate, E, the 
 upper or Mansard plate supported by the 
 Mansard or flaring rafters C, which 
 flares 2 feet off the perpendicular. D, is 
 
 FIG. 41. 
 
 the deck or upper rafters, and B, a tie or 
 ceiling beam which gives a good attic 
 room. Half the roof only, namely, the 
 left side, is shown in this cross-section, 
 Fig. 37. 
 
 1 
 
 sotrcJ 
 
 FIG. 38 ELEVATION OF FRAMING. 
 
ROOF FRAMING MADE EASY. 
 
 FIG. 39 PLAN OF MANSARD RAFTERS. 
 
 A comparison between the plan Fig. 
 39. and the elevation and cross section 
 will make clear the full construction of 
 the roof and enable any mechanic to lay 
 out, frame and raise roofs of this class. 
 The elevation and plan show one end 
 (the right) hipped and the other (the 
 left) gabled. In order to determine the 
 exact length of the Mansard hip rafter, 
 the method is illustrated in Fig 40. It 
 is simply to raise up on the seat X Z. of 
 the hip the height of the pitch 9 feet 
 and 6 inches and to join this height 
 with Z. 
 
 The deck or upper rafters are framed 
 in the way I previously described. Fig. 
 41 represents the proper shape to frame 
 the top cuts of Mansard rafters to pre- 
 vent their slipping under the upper 
 plate. 
 
 CHAPTER XVI. 
 
 HEMISPHERICAL DOMES. 
 
 THE roof presented to readers of this 
 chapter is one well worthy of 
 careful study and working out. 
 It is of a kind which occurs on 
 many houses now-a-days on the tops of 
 towers for domes, etc. I should there- 
 fore recommend that those who have 
 leisure time work it out on a board to a 
 large scale . 
 
 A, B, C, D, E, F, G, Fig. 42, is the 
 plan, a perfect circle, of twelve feet 
 diameter or six feet radius, A D and B 
 F two diameters or centre lines inter- 
 secting in the centre. The dome is 
 hemispherical or half a ball, or sphere, 
 therefore the elevation H J I. is struck 
 from a six foot radius. A pair of tram- 
 mel points and rod may be used in strik- 
 ing out these curves, but, should these 
 
 be lacking, a by $ inch strip and a 
 couple of brad awls will do the job very 
 handily. 
 
 H, I, are the plates made of thick- 
 nesses of stuff, and I J one pattern 
 rafter. J is the top cut and I the bottom 
 cut. They are, of course, similar. The 
 rafters for this roof may be gotten out 
 of H or 2 inch stuff, fastened at the 
 joint by a cleat as shotvn at I J. There 
 will be eight rafters required (if it is in- 
 tended to cover it vertically) as B X, 
 C X, D X, E X. F X, G X, H X. 3 X, 
 and these will have horizontal sweeps 
 nailed in between them denoted 
 here by 1. 2, 3, 4, 5, in the ele- 
 vation/ The exact position of these 
 sweeps is determined by dividing the 
 quarter circle H J into six equal parts 
 and then from the division points, draw- 
 ing lines parallel to H I. These will be 
 the centre lines of the edges oi the 
 sweeps. 
 
 Similarly they are shown on the plan 
 below as 1, 2. 3, 4, 5. to X F. which is 
 as they will look from above. Their 
 exact length for each course from 1 to 5 
 will be found by measuring the sweeps 
 from A X to G X. deducting half the 
 thickness of the rafters on each end. 
 Patterns should be made for each 
 course as it will be seen that each is 
 struck from a different radius, shorten- 
 ing as they ascend to the top. 1 in the 
 plan corresponding to 1 in the elevation 
 and so on up. It will, therefore, be 
 clearly understood how to frame such a 
 roof as this when boarded or covered 
 vertically. 
 
 To find the exact shape and size of the 
 covering boards, take any one of the six 
 divisions and set it off on each side of G, 
 the point where X G, cuts the quarter 
 circle A F, at G; produce X G, indefi- 
 nitely. Now, with the dividers set off 
 
ROOF FRAMING MADE EASY. 
 
 on G S, the six distances, H I, 1 2, 2 3, 
 3 4, 4 5, 5 J; and draw lines from these 
 points square to G S. Next again with 
 the dividers make these squared lines 
 each equal in length those dotted lines 
 passing through G X, from T to U, and 
 draw the curves as shown, which will 
 give the exact length and curvature of 
 the boards to be bent round I J. There 
 
 will be 12 of these for each quarter cir- 
 cle on plan or 24 for the whole roof. If 
 this be laid out on a cardboard sheet it 
 will be found to fit exactly. 
 
 To cover this roof horizontally, all the 
 rafters, 24 in number, must be set ver- 
 tically or plumb, as B X. 1 X, 2 X, etc. , 
 to A X, and it would be best to have a 
 finial or block at the top to receive the 
 top ends of the rafters. In order to find 
 the shape of the level covering boards, 
 
 Fia. 42. 
 
34 
 
 ROOF FRAMING MADE EASY. 
 
 FIG. 43. 
 
 divide the curve Fig. 43, into 6 equal 
 parts and draw line from division points 
 parallel to plate. Join A 1. 1 2, 2 3. 3 4, 
 4 5, 5 6, and produce these joining lines 
 till they cut the centre line produced 
 indefinitely. The points where these 
 produced lines intersect the centre line 
 will be the centres for the curves of the 
 covering boards as represented in the 
 engraving. 
 
 CHAPTER XVII. 
 
 To FRAME A CIRCULAR ELLIPTIC 
 DOME. 
 
 READERS will observe that I have 
 here treated a roof with which 
 most mechanics are unfamiliar, 
 and it is a pleasure for me to de- 
 scribe it for this reason. A C D B, Fig. 
 44, is the plan or outside line of the 
 plates which measure 12' 0" x 20' 0", or 
 the roof will be 20 feet long and 12 feet 
 wide. Across IK R its section will be 
 a semi-circle, or A E B and across F K 
 S its section will be a semi-ellipse (not 
 an oval, as this figure is often mis- 
 
 called). As there may probably be some 
 readers who are not acquainted with the 
 proper methods of striking a semi- 
 ellipse, as H M L H C really is we will 
 proceed to illustrate and describe the 
 best in use. 
 
 In referring to the engraving, Fig. 45, 
 we will suppose A B to be 20 feet long 
 and C D 6 feet equal to the E F 011 Fig. 
 44. Now to find exact curve of the 
 ellipse draw the line R C F parallel to A 
 D B. and draw F E and B F. Now 
 divide the sides E C and C F each into 
 five equal parts as 1 2 3 4 and E and join 
 these dividing points with the angle A, 
 as4A, 3A, 2A, 1A. and CA. Similar 
 lines are drawn on the other side to B. 
 After this is done, divide the sides AE 
 and BF each into five equal parts and 
 join the dividing points with C, as AC, 
 1C, 2C, etc ; do likewise on the side BF. 
 Next proceed to trace the elliptic curve 
 through the points where the joining 
 lines intersect each other, as shown in 
 the diagram, Fig. 45. This is the exact 
 method of drawing an ellipse, but as it 
 is not always applicable in the case of 
 large spans like on this roof I would 
 
ROOF FRAMING MADE EASY. 
 
 35 
 
 FIG. 44. 
 
 recommend mechanics to use the tram- 
 mel method illustrated in Fig. 46. The 
 trammel is made of two pieces of 
 grooved stuff halved together in the way 
 denoted by the heavy black lines in the 
 engraving. In the groove two little 
 runners slide, and to them is loosely at- 
 tached a rod as ACB in Fig. 46. 'The 
 distance from A to B, Fig. 46, is equal 
 to half the long diameter of the ellipse, 
 or from A to I or I to C. on Fig. 44, and 
 the distance from C to B is the same as 
 the height on from I to H, on Fig 44. 
 At B the pencil is placed, and being 
 moved round, as it were, the slides run 
 in the grooves and the pencil follows 
 and outlines the desired elliptic curve. 
 By means of the trammel the full ellipse 
 may be outlined as shown by the dotted 
 
 line on the under side. Fig. 47 
 gives another, but less accurate, 
 method of obtaining this curve. 
 AB is the length, CD the height. 
 Take a rod and set off the length 
 AC from D on the line AB . This 
 will give the two face or points E 
 and F. Drive nails or pins into 
 these points and to them attach a 
 btring which will reach exactly to 
 D. Now place a pencil inside the 
 string at D and trace the curve as 
 shown. This is a very simple way 
 to gain an elliptic curve, but is 
 not a very true one on account of 
 the stretching of the string. It is. 
 however, good enough for small 
 curves. Where the trammel is 
 not available ellipses cannot jpos- 
 sibly be accurately described with 
 compasses . 
 
 Having described the best 
 methods of striking out elliptic 
 curves we will refer back to Fig. 
 44. We find the cross and longi- 
 tudinal or length sections to be a 
 circle and an ellipse. Now to 
 frame the dome join BC and AD 
 on the plane, and on each side of 
 the centre line set off half the 
 thickness of the hips inch, inch 
 and a-half or two inches, accord- 
 ing to the thickness . Next draw 
 the seats of the jack rafters, nine on 
 each side, and five on each end, reaching 
 from the plates to the hips. 
 
 To find the necessary outline of the 
 hip rafters, which, being the intersection 
 of an ellipse and a semi-circle will be 
 also of elliptic form, from the centre K, 
 raise up the height K J, equal to H I, 
 and proceed to strike the curve by any 
 of the methods described; A J D, J D, 
 will be the outline of the top edge of the 
 hip rafter. For the jacks draw lines 
 from the hips on the seat lines cutting 
 the quadrant E B, in N. O P Q, which 
 will give the exact lengths of the semi- 
 circular jacks N, on plan; O, on section, 
 to O, on plan, and so on up to R, which 
 
 FIG. 45. 
 
 FIG. 46. 
 
36 
 
 ROOF FRAMING MADE EASY. 
 33 
 
 AT 
 
 FIG. 50. 
 
 Fia. 51 
 
ROOF FRAMING MADE EASY. 
 
 37 
 
 rafter will be a quadrant as E B. In the 
 same way the two elliptic jack rafters 
 on each side of K F, as M, and L, are 
 found by the dotted lines. The plumb 
 cuts will be, as usual, plumb, and the 
 side bevels will be those seen on the plan. 
 To those who have the time and 
 patience, I would recommend that they 
 make scale models of these roofs from 
 
 engraving. In striking this plan, any 
 of the methods which I described in the 
 last chapter, or by the simple and 
 accurate method which I here illus- 
 trate at Fig. 48. It consists of 
 one horizontal straight edge A B, 
 tacked on the floor on the line of 
 the major axis or long diameter of the 
 ellipse, and a second straight edge C E, 
 
 the descriptions given in previous chap- 
 ters and in this. Nothing verifies and 
 proves the value of a system of lines 
 like an accurate model or true repre- 
 sentation of the actually constructed 
 roof on a small scale, and it is my great 
 desire to publish nothing which is not 
 both accurate and necessary. 
 
 CHAPTER XVIII. 
 
 To FRAME AN ELLIPTIC DOME WITH AS 
 ELLIPTIC PLAN. 
 
 AT Fig. 49, the plan of the elliptic 
 roof. letABCDEFGHIJK 
 L M N O and P be its shape on 
 the outside line of the elliptic 
 plate, cut in sweeps as shown in the 
 
 :FiG. 48. 
 
 set on the minor axis or short diameter 
 below it . These are represented in the 
 engraving. A trammel rod or tracer is 
 made with the distance from the pencil 
 to the farthest nail against the short 
 straight equal to A C or half the long 
 diameter, and the distance from the 
 pencil to the nearest nail sliding against 
 the long straight edge, equal to C D or 
 half the short diameter. The elliptic 
 curves may by this method be accurately 
 struck to the size desired. 
 
 N 
 
38 
 
 ROOF FRAMING MADE EASY. 
 
 In this dome roof I have inserted a 
 boss in the centre to receive the top cuts 
 of the elliptic rafters, all of which rad- 
 iate from the centre to the outside edge 
 of the plate terminating at A B C D, etc. 
 The rafters which will stand over the 
 plan, Fig, 49, on M E will be A D and D 
 B on Fig. 50, which is the projection or 
 view of elliptic rafters nailed in position. 
 
 Each set of two rafters, as AI. BJ, 
 CK, DL, Fig. 49, etc., must be struck 
 out separately with the major axis or 
 long diameter of each, being the plan 
 length as AI, BJ, etc., with the minor 
 as CD, Fig. 50; great care and accuracy 
 is necessary in striking out each set so as 
 to have them, the curves, absolutely cor- 
 rect and appear as at Fig. 50 when raised . 
 
 In order to determine the shape of the 
 covering boards or roof covering proceed 
 to Fig. 51 and draw the long diameter 
 LMK, also the short diameter MA, and 
 
 FIG. 52. PLAN OF PLATE, RAFTERS 
 AND SWEEP. 
 
 strike the elliptic elevation of the roof 
 LAK. Divide the quarter ellipse into 
 ten equal divisions as denoted by A B C 
 D E F G H I J K and let fall lines 
 square to M K as A M, Bl, C2, etc., and 
 produce these across the plan below, to 
 represent 1 boards bent across the 
 rafters. To find the exact shape of these 
 covering boards join the division points 
 on the curve A K, and produce each till 
 it cuts the line M K produced. The 
 points where these lines intersect will 
 be the centres from which the curved 
 boards, which are necessary to bend 
 across the rafters, may be struck in the 
 way represented in the engraving, Fig. 
 51. For the purpose of fully proving 
 the correctness of the above methods I 
 would urge upon mechanics to make a 
 scale model as before in cardboard of 
 this roof, thus proving the exactness of 
 the methods set forth in the foregoing. 
 
 J L, K 
 
 FIG. 53. MOLDED RAFTERS. PLATE 
 
 AND SWEEPS. 
 
 CHAPTER XIX. 
 
 FRAMING A CIRCULAR MOLDED ROOF 
 
 TOWER. 
 
 T T AVING before described the proper 
 LX| methods to be followed in fram- 
 1 1 ing a straight sided or conical 
 roof with a circular base of plan, 
 in this chapter I will give readers the in- 
 formation necessary to know in laying 
 out and framing a roof with a molded 
 form of rafter. As there are many of 
 these constructed now-a-days it will no 
 doubt be welcome to studious mechanics. 
 By referring to Fig. 52 it will be seen 
 that the plate or plan is a complete cir- 
 cle, asABCDEFGH, made up in 
 two thicknesses of sweeps cut out as 1. 
 
 FIG. 54. How TO LAY OUT CURVE OF 
 RAFTERS. 
 
ROOF FRAMING MADE EASY. 
 
 39 
 
 have shown by the joint lines. The 
 molded rafters (of a bell shape) are, as 
 seen on plan, eight in number and must 
 be made exactly to the curvature repre- 
 
 f 
 It 
 
 FIG. 55. METHODS FOR OBTAINING SHAPE OF 
 COVERING BOARDS. 
 
 sented on the projected framing of the 
 roof or rafters, etc., raised as seen at 
 Fig 53. 
 
 In order to obtain the exact flexure 
 or curves the writer has followed the 
 following method with much success 
 and shaped many molded rafters to the 
 design intended by the architect: 1st, 
 make a laying-out floor out of a number 
 of boards placed level on planks, or 
 sweep an ordinary floor clean, big 
 enough to lay the roof out in, and draw 
 any base line as A B in Fig. 54; also 
 divide it in the centre at C, and draw 
 an exactly vertical or plumb line to it, 
 as C D, then divide the height line C D 
 into 12 equal parts as 1 2 3, etc., and 
 draw through these lines parallel to A 
 B, as 1 1, 2 5J, and so on up to 11. Now 
 set off the lengths 11,22, and so on up, 
 and trace the bell- shaped curves to the 
 desired flexure . If the architect furnish 
 only a ^-scale drawing of the roof, the 
 scale drawing can be similarly lined off 
 and the lengths taken with the scale 
 rule, transferred and relaid on out on 
 the floor, thus obtaining the curve. 
 
 When the curve 
 is laid out on a 
 drawing-board the 
 pattern rafter is 
 made by placing 
 the planks on the 
 lines and marking 
 on it the length 
 before as described 
 and in the manner 
 illustrated in Fig. 
 54, where a rafter 
 sawn out is de- 
 lineated on the left 
 hand side, as A D, 
 and the thickness 
 of the 6 -inch boss 
 at D, which is in- 
 serted for the pur- 
 pose of giving a 
 better nailing at 
 the peak, is taken 
 from the top cut. 
 This boss is also 
 seen on the plan, 
 Fig. 52 at X, and 
 on the projection 
 of set-up rafters, 
 Fig. 53 at M, where 
 it is obviously nec- 
 essary in order to 
 obtain a firm nail- 
 ing for the top ends 
 of the molded raft- 
 ers. At Fig. 53 the 
 mechanic will see 
 how a series of 
 circular strips or 
 sweeps as they are 
 
40 
 
 ROOF FRAMING MADE EASY. 
 
 technically termed, are nailed in, rang- 
 ing from the plate to the peak. These 
 are essential when it is intended to 
 board the roof from bottom to top, for 
 the purpose of nailing the boards to 
 them. 
 
 They are sweeps or arcs of circles and 
 struck from different radii, decreasing 
 as they go up. This will be readily un- 
 derstood by studying the plan, Fig. 52, 
 where the dotted lines represent the out- 
 side edges of the sweeps shown on Fig. 
 53. As there are 8 intervening spaces 
 between the rafters, and there are 9 in 
 the height, there will be 72 needed al- 
 together or 8 of each kind, and they 
 may be solidly nailed in the way indi- 
 cated in the engraving, Fig. 53. 
 
 This form of roof may be covered in 
 two ways, either vertically or horizon- 
 tally. When covered vertically, the 
 sweeps described above are inserted and 
 the shape of the covering boards de- 
 termined, in the following manner. Let 
 ABCDEF GHI JKLM NO Pon 
 Fig. 55 be the plan of the outside edge of 
 the circular plate, and A X, C X, E X, 
 G X, I X, K X, M X, and O X be the 
 rafters, all abutting against the boss X, 
 on plan, in the manner seen at D, Fig. 
 54 ; also suppose the dotted lines on Fig. 
 54 represent the outside edges of the 
 sweeps. Now to determine the shape of 
 one covering board, produce X C to U 
 and on the line E U. taking U as centre, 
 proceed to strike the arcs a b, c d. e f, 
 g h, i j, k /, m n, o p, q r, s t cutting U 
 C at the points 123456789 10. Then 
 set off on each side of the line U C on 
 each arc the distances from X B on the 
 p\B,u,taking the exact full length of the 
 curve and not on a straight line, each 
 corresponding as shown in the engrav- 
 ing. For instance, s c t must be the 
 full length of the curve BCD, and so 
 on with each all the way up . 
 
 If the roof is intended to be boarded 
 horizontally then more rafters must be 
 inserted, in order to give a better nail- 
 ing, and this roof will then need sixteen, 
 instead of only eight, as before, see Fig. 
 55. To obtain the shape of the horizon- 
 tal covering boards, proceed to the upper 
 engraving and draw Q R equal to M E 
 below, and S T vertical to it. Also set 
 off the bell-shaped curves as shown. 
 
 To find the shape of the first or bot- 
 tom board, assume R V to be a straight 
 line, and produce it till it cuts the verti- 
 cal line S T at W, then with W as cen- 
 tre and radii W R and W V, strike the 
 two arcs Q R Z and Q V Y . Finally, 
 to find the exact length of this bottom 
 board, take any curved distance on plan, 
 as A B. Fig. 55, and set it off eight times 
 from Q to Z, as indicated by the marks. 
 
 This will give half way round, which 
 doubled will give entire circular cover- 
 ing board for the first section. By con- 
 tinuing this process up to the top, all the 
 horizontal boards may be laid out. 
 
 CHAPTER XX. 
 
 To FRAME A GOTHIC TOWER ROOF OF 
 FOUR-CENTRE SECTION. 
 
 1HERE set before readers, a form of 
 roof which is fast becoming popular 
 on account of its uniform curves. 
 
 As the section of the roof is a com- 
 bination of curves, we must first pro- 
 ceed to lay it out . On a large floor or 
 platform draw the spring line AB, Fig. 
 56. Divide this line AB into 4 equal 
 parts as 1, 2, 3 and 4; also from A and 
 
 FIG. 56. 
 
 B, draw AC and BD square to AB. Now 
 with A as centre and A2 as radius strike 
 the curve 2C, cutting AC at point C. 
 likewise strike the curve 2D cutting BD 
 at D. This process locates the desired 
 centres for the different curves of the 
 dome or tower section. 
 
 With 1 as centre and 1 A length of 
 radius, strike the short curve, or arc A 
 E and with 3 as centre and same radius 
 strike B F. This gives 2 arcs, next with 
 C as centre, and allowing the trammel 
 pencil to be just tangent to B F at F, 
 describe the arc F G. In a similar 
 manner describe the arc E G on the left. 
 This process carefully followed out will 
 
 five the exact four-centre gothic section, 
 ut it must not be followed in every 
 plan where a roof of this section is 
 shown, as the position of the centres may 
 not be placed or divided off as is shown 
 
ROOF FRAMING MADE EASY. 
 
 above, and a detail or layout of the roof 
 may be necessary to determine their 
 position. The foregoing description, 
 however, will make the work familiar 
 and easy. 
 
 In order to lay out the rafters for this 
 roof, proceed to Fig. 57, and lay out the 
 plan full size A B C D, also draw the 
 diagonals A D and B C. the seats of the 
 hips, with the jacks abcdefghij, 
 against the hip seat c X. On the line 
 B D, divided in half at E. raise up the 
 gothic section line, and from this sec- 
 tion make a paper or wood pattern rafter 
 to the curve B 12. in the manner shown 
 in the engraving. Divide B 12, into 
 twelve equal parts, as 1, 2, 3, 4, etc., 
 and from each division point draw a 
 line square to the line BED, and pro- 
 duce these lines to the hip seat. 
 
 B 12, will, of course, be the common 
 rafter standing over E X. Each jack 
 will, because the hip rafter is on a mitre 
 or angle of 45 degrees, be shorter as they 
 go down from X to C, and their lengths 
 will be as K 11, L 10, M 9, N 7, and so 
 on down to B. 
 
 At Fig. 58, readers will see a compar- 
 atively simple method which may be 
 followed to obtain the top side bevel of 
 the jack rafters. A B. is the common, 
 showing its upper edge. Set off rafter 
 No. 10 from A to C. C D, being the ver- 
 
 FIG. 57. 
 
 FIG. 58. 
 
 tical or plum cut. Square across from 
 the upper edge corner, from G to C, as 
 C F, and from C D, set off the thickness 
 of the jack rafter, 2 inches, or 3 inches, 
 or whatever it may be. The bevel will 
 be as shown in the engraving. 
 
 B X. From the points where these 
 dotted lines cut B X, draw up square to 
 BX, lines of an indefinite length. Now, 
 commencing from B, on line B E, take 
 the first division 1, and set off the 
 height from the line to 1, on the 
 first line on the hip seat, also height 
 at 2, 3, 4, 5, and so on up to 12". 
 To be explicit, I would say transfer 
 these heights from perpendiculars 
 on B E, to perpendiculars on B X. 
 Next trace the curve, F B, through 
 the points 12, 11, 10, etc., and the 
 proper outline of hip rafter will be 
 found. 
 
 CHAPTER XXI. 
 
 To FRAME A TRUSSED ROOF OF 
 
 LARGE SPAN ON THE BALLOON 
 
 PRINCIPLE. 
 
 THAT carpentry is a progres- 
 sive art is a truism that the 
 observer will not hesitate to 
 admit, and a careful exami- 
 nation of the timber structures be- 
 ing erected in the United States 
 to-day will impress the examiner 
 with the fact that it is also a liberal 
 art. This is, without doubt, one of 
 the chief reasons why wood has 
 not been entirely driven out of the 
 field by its great competitor, iron, 
 as it can be readily and econo- 
 mically employed where the latter 
 
ROOF FRAMING MADE EASY. 
 
 
 \ 
 
 \ 
 
 ' ' \ X 
 
 * ' / v X 
 
 V ___ _ . _/_ \ X 
 
 I / 
 
 \ I / 
 
 \ I ' 
 
 - I / 
 
 \i ,_ _K 
 
 /<r/ - 
 
 / x / 
 
 / /\ " 
 
 / x / 
 
 FIG. 59. 
 
 material would be inadaptable. The 
 numerous and exceedingly artistic dwell- 
 ings which are erected in all parts of the 
 country attest this, and while designing 
 them the architects have endeavored to 
 devise new forms of construction which 
 might enable them to produce an effec- 
 tive design and at the same time be a 
 cheap one to build. An illustration of 
 this will be seen in the sketches which 
 are here introduced, as they explain a 
 unique method of balloon framing which 
 was adopted in a church, the building 
 being a frame structure, and having an 
 auditorium measuring 56 feet square. 
 The architect wished to avoid inserting 
 the usual form of trusses and, after 
 careful study, he devised the manner of 
 construction here shown . Fig. 59 is the 
 plan of the auditorium, E A D G C I B 
 E being the outside line. B F A, A L 
 D, D H C and C J B are the trusses 
 which the reader will notice do not span 
 the roof at right angles in the way gen- 
 erally followed, but are placed at an 
 angle of 45 degrees across the angle of 
 the corner. Each of these were 25 feet 
 on base line and were framed in the way 
 represented in the isometrical projected 
 view (see frontispiece), without any tie 
 beam, yet of a form statically strong 
 enough to support the rafters and shing- 
 ling placed upon it. They were then 
 
 placed diagonally across the plan so 
 that their seats formed a square, as it 
 were, within a square. This the reader 
 will comprehend better by referring 
 again to Fig. 59, where the dotted lines 
 A D, D C, C B and B A, are the seats of 
 the trusses, and a close observation of 
 the projection (see frontispiece), will give 
 him a perfect idea of how they were 
 positioned. The hip rafters E F, K, D, G 
 H and I J, rested against the trusses 
 which supported on their peaks the up 
 per wall plate or purlin on which the 
 ventilator was raised, and against which 
 the jack rafters from the trusses rested. 
 A peculiar feature of the construction, 
 which the reader will notice, is that the 
 principal rafter of the trusses in each 
 plane of three, as D I and D H. in the 
 plane G H L K. was partly a hip and 
 partly a valley rafter at the same time, 
 because the jacks were cut from the 
 plates below to them and from them to 
 the purlin above; but the sides still 
 formed separate planes and, when cov- 
 ered, showed a straight surface, as G H 
 L K, Fig. 59. Taking the whole con- 
 struction as a piece of statical and 
 economical design, it savors more of en- 
 gineering than architecture, but as an 
 uncommon piece of roof framing it is 
 a most ingenious method of solving an 
 old problem in a new way. 
 
ROOF FRAMING MADE EASY. 
 
 FIG. 61. ROOF TIMBERS WHEN RAISED. 
 
 CHAPTER XXII. 
 
 To FRAME A ROOF OF UNEQUAL HEIGHTS 
 OF PITCHES AND PLATES. 
 
 HAVING described in previous chap- 
 ters roofs springing from wall 
 plates on the same level, I will 
 show in this the proper method 
 to be followed in framing two roofs 
 where the plates are at different heights 
 and the roofs at different pitches. 
 These roofs to those unused to them 
 appear very difficult to frame, but are 
 really not so. 
 
 Fig. 61 will give readers a full con- 
 ception of the timbers forming the two 
 roofs as they will appear when "raised" 
 or set up in their permanent position. 
 It will be noticed that the wall-plate of 
 the projection or bay is about four feet 
 higher than the plate on the main wall 
 of the house, also that the rafters are 
 cut on different pitches. 
 
 If the reader cannot clearly under 
 stand this I would refer him to Fig. 62. 
 which is a sectional view of the roof 
 when raised through the line A B, on 
 Fig. 63, the plan of roofs. Here the 
 different levels of the plates will be seen 
 
 and another view of the rafters and stud 
 wall of the projection. As the timbers 
 are all marked very little description is 
 necessary. 
 
 Concerning the methods to be fol- 
 lowed in finding the lines for this form, 
 it is as f ollows : C D E F. Fig. 63, is the 
 plan of the extension plates, I and J 
 being the plates of the main house wall. 
 
 FIG. 62. SECTION ON LINE A B. 
 
ROOF FRAMING MADE EASY 
 
 G C and G F are the seats or plans of the 
 valleys determined by the intersection 
 of the two peaked roofs. To find the 
 exact length of these valleys raise up 
 square the pitch G K. Set off the height 
 G K equal to A B Fig. 62, and join K F, 
 which line is the exact length of the 
 valley rafter as seen at Figs. 61 and 62, 
 also the length of G C. 
 
 Next, to find the lengths of the jack 
 rafters on each side of the valleys set a 
 
 f 
 
 JDL 
 
 FIG. 63. PLAN OF ROOFS. 
 
 pair of compasses to the line K F, and 
 with F as centre cut the line H G L at L 
 and join L F. Now if the jacks from 
 the ridge line H G be produced to the 
 line L F their exact length will be given 
 with the side or top edge bevel. To 
 obtain the length of the jack rafters on 
 the main roof, the feet of which nail 
 against the valleys, draw R M parallel 
 to L F and the lengths of these jacks 
 will be thus found. 
 
 CHAPTER XXIII. 
 
 To FRAME A HIP AND VALLEY ROOF 
 OF UNEQUAL PITCH. 
 
 FIGURE 64 is the projection of the 
 roofs completed, and it will be 
 noticed that they are of different 
 pitches and widths. A B C D E F 
 G M H K IJ, Fig. 65, is the plan of the 
 building. A B is a gable end, and A N 
 is the length of the common rafter ; also 
 D E is a gable end. D O being the 
 length of the common rafter each has a 
 ridge L N X and P O Y. The main roof 
 
 is hipped, having four principal hip 
 rafters with jacks. The intersection of 
 each of the L's on the building with or 
 rather in the main roof gives three val- 
 iey rafters and creates the framing 
 p oblem which is to be worked out. 
 
 Proceed to lay out the plan of the 
 plates, hips, valleys and ridges as shown 
 on Fig. 66, and join I G and H Q giving 
 the peak R ; also draw the dotted lines 
 K R F and M R X in Fig. 65. To ob- 
 tain the length of the main hip rafters 
 square up from R and set off on the 
 square line the pitch height R C equal 
 to E T. Join H S, which will be the 
 exact length of the hip rafter, with the 
 bevel S for the top cut and the bevel H 
 for the bottom cut. 
 
 FIG. 64. ELEVATION OF ROOF. 
 
 To find the lengths of the jacks set a 
 pair of compasses or a rod at Hand with 
 H S as radius sweep the arc S V . Join 
 V where the arc cuts the line R F and 
 H, also draw the jack rafters square to 
 the plate K H until they reach the line 
 V H, and this line will determine their 
 length and the bevel U will be the cut 
 across the top of each against the hip, 
 that at I being the plumb cut. Reverse 
 cuts are made to go against the hip I R 
 and G R, from the plates K I and G F. 
 
 To find the lengths of the jacks placed 
 on the plate G M H. proceed to raise up 
 from R square to G R, the pitch R Z ; 
 join Z G and with G as centre and rad- 
 ius G Z sweep the arc Z X, cutting M R 
 N L in X; join X G. Set off the jack 
 rafters in the manner shown, reaching 
 from the plate G M H to the line G X 
 and their lengths will be thus found. 
 The bevel W will be the cut across the 
 top edges of jacks in getting the cut to fit 
 against the hip. It will also be the bevel 
 reversed on the opposite to fit against 
 the hips standing over Q R and R I. 
 
 In framing the valleys to stand over 
 the seats X C and X J, first find out 
 where the ridge will penetrate the main 
 roof. This may be simply done by set- 
 ting off on the line E T, the half pitch 
 height L N and drawing out square as 
 1, 2. The point 2 will be the point 
 where the ridge L N will enter the main 
 roof. This must be transferred over to 
 cut the ridge X ; and J X, C X will be 
 the seats of, the valleys. 
 
ROOF FRAMING MADE EASY. 
 
 45 
 
 FIG. 65. LAYOUT OF RAFTERS 
 
 To find the valley rafters, square up. 
 from X. which will be the line X 5, on 
 it set off the ; pitch N L, and join J 5 
 which will be the exact length of the 
 valley rafter with the top and bottom 
 bevels as indicated on the diagram. It 
 will be here seen that I have prolonged 
 one valley from X till it cuts the centre 
 line of the main roof and at the point 
 where it cuts raised up the whole pitch 
 of T E, as 6 A. This is done for the 
 purpose of determining the lengths of 
 the jack rafters, and is necessary to find 
 the angle. C 6 F is the angle. To find 
 the short jacks reaching from the hip 
 Q R to the valley C X, join C F and 
 divide it into two equal parts as 6 7. 
 Now with C as centre and C 4 as radius, 
 sweep the arc 4 8, cutting 7 6, produced 
 at 8 and join C 8 ; next draw the jack 
 rafters from R Q to the dotted line C 8, 
 which will be their lengths and the bot- 
 tom cuts across the top edge of each 
 jack, nailing against the valley rafter 6 
 C, will bethebe-e!9. 
 
 The jacks from the ridge L N X to the 
 valley J X. are found similarly by set- 
 ting the compasses to radius J 5 and 
 sweeping the arc cutting the line X R; 
 then by joining this point with J by the 
 dotted'line seen to the left of the valley, 
 the jacks may be drawn as before. 
 
 For the valley F Y raise up square 
 trom Y the pitch Y Y equal to P O, and 
 join Y F for the length of valley. The 
 jacks are found by the process described 
 before and the bevels are clearly seen . 
 Each hip and valley rafter should be 
 gotten out separately to avoid con- 
 fusion, and the diagram closely studied 
 as the system is simple and easily 
 understood. 
 
 FIG. 66. FLAN OF ROOF 
 
46 ROOF FRAMING MADE EASY. 
 
 CHAPTER XXIV. 
 
 To FRAME A ROOF OF UNEQUAL LENGTHS 
 OF RAFTERS. 
 
 LET A B C D in Fig. 67 be the square 
 plate or lower plate, which has 
 short, or curb rafters supporting 
 a circular plate, E F G H, on 
 which rests a drum, or short cylindrical 
 tower as E C D F, Fig. 69, topped by a 
 roof with curved rafters. By referring 
 to the plan. Fig. 67, .it will be seen that 
 the seats of the rafters will be of differ - 
 
 PLAN OF PLATES AND RAFTERS. 
 
 eiit lengthening from the centre, or 
 number 6, to the corner or hip rafter I, 
 and that this occurs on all four sides of 
 the square plate. As the seats are of 
 different lengths the rafters will also be 
 of different lengths, though they have 
 the same rise or pitch, as X Y in Fig. 68. 
 In this figure the different lengths of 
 rafters will be distinctly seen decreasing 
 in size from the hip or angle to the 
 centre of the plate, this occurring on 
 each side, which will necessitate 8 sets 
 of five rafters, cut with right and left 
 hand bevels on the plate, also one set of 
 
 FIG. 69. PROJECTION OF ROOF AND 
 DRUM. 
 
 4 with square cut on plate, as number 6. 
 Each succeeding rafter will have differ- 
 ent top and bottom bevels, and require 
 great care in laying out. so as to cut the 
 timbers without waste, so that it would 
 be wisest to lay out and cut them in sets, 
 one for each side. The top and bottom 
 cuts as represented in Fig. 69, are also 
 notched to fit over the plates and thus 
 prevent their slipping; this will also 
 demand care in laying out, because each 
 notch will have a different bevel. The 
 got hie roof on the drum may be struck 
 out to the curve shown and rafters cut 
 out. As all the rafters are the same 
 length, they can be sawn from one pat- 
 tern, and set up in the manner which I 
 have already described. 
 
 FIG. 68. DIFFERENT LENGTHS OF 
 RAFTERS. 
 
 CHAPTER XXV. 
 
 To FRAME A ROOF WITH PITCHED 
 RIDGES. 
 
 THE following roof of an unusual 
 kind will be found of value to 
 those carpenters who live in the 
 country or whose duty it is to 
 construct barns, or other special build- 
 ings, where great room is required in 
 the roof or attic. 
 
 The engraving. Fig. 70, is an isometric 
 view of the roof, and as will be seen it 
 consists of a roof of four gables on a 
 square plan, with four valleys and four 
 ridges which rise on a pitch from the 
 peaks of the gables and terminate at the 
 peaks of the valleys, giving the effect as 
 shown. The rafters of the gables are 
 half or mitre pitch, and twelve and 
 twelve 011 the steel square. The peak of 
 the valleys represented in Fig. 71 is 4 
 
ROOF FRAMING MADE EASY. 
 
 47 
 
 / O 
 
 Fi<;. 7*2 LAYOUT OF ROOF. 
 
48 
 
 ROOF FRAMING MADE EASY. 
 
 feet higher than the gable peaks so that 
 the ridges rise on pitch in the manner 
 shown in the cross section Fig. 71, thus 
 forming a very peculiar and unusual 
 form of roof. 
 
 In order to frame this roof in the sim- 
 plest manner proceed to Fig. 72, and let 
 A E, B, H, D C, be the plan of the roof 
 A F, B F. D F and C F, being the seats 
 of the valleys. E F, H F, G F, and I F, 
 being the seats or plans of the hips. To 
 find length of valley from F square up 
 as F, A J, equal in height to at C Fig. 71, 
 and join J C, Fig. 72 for the lengths and 
 bevels of the four valley rafters. Now 
 for the eighteen jack rafters the author 
 has found it most convenient to develop 
 the roof in order to prove the accuracy 
 
 FIG. 70. GENERAL APPI ARANCE OF 
 ROOF. 
 
 of the layout ; therefore on C G D, erect 
 one gable to stand over C G D, as C K D. 
 From D, make D M, equal in length to 
 F J, and K M, equal in length to the 
 ridge E., C, or C F, Fig. 71. Divide off 
 on K M, Fig. 3, the jack rafters as on K 
 M, Fig. 71, and draw them parallel to 
 K D, in the way illustrated at Fig. 72, 
 as N O, P Q R S, T U, V W, and X Y. 
 The bevels at O, and N, Fig. 72, will be 
 the side bevels against the ridges and 
 valleys, being reversed for 
 different right and left 
 sides, the down or verti- 
 cal cut of the bottom ends 
 of the jacks nailed against 
 the valley sides will be as 
 the pitch of the valleys 
 and the top cuts as that of 
 the gables or mitre cut. 
 Carpenters should cut this 
 diagram out, as it is print- 
 ed, to prove the accuracy 
 
 FIG. 71. VALLEYS, RAFTERS AND 
 RIDGES . 
 
 of the methods, or first paste the en- 
 graving on cardboard and then cut 
 out as follows: Cut out the whole 
 plan, A E B H D, M K L C, and A; 
 then make a slight cut with a pocket- 
 knife or chisel from C, to K, and from 
 K, to D, also across C G D. Fold over 
 the development until K, is over G D 
 M, is over D F C L over C F, and L, 
 and M, joined together are over F, with 
 the ridge L K, over G F. 
 
 CHAPTER XXVI. 
 
 To FRAME A ROUND-HOUSE ROOF. 
 
 ASSUME the roof to be semi circular 
 in plan as represented in Fig. 74, 
 and to have a pitched roof with 
 a ridge, the pitch being half, or 
 12 and 12 on the steel square, as seen at 
 D, G, F, Fig. 74, where the lengths of 
 the rafters and bevels are delineated. 
 A, B, C and D, E, F, are the gables on 
 the plan Fig. 74 seen on the elevation 
 Fig. 73, with windows and doors in 
 same. In order to find the length of the 
 common rafter simply raise up from E, 
 Fig. 74, the pitch or rise E, G and join 
 D, G. As the outer plate line A, X, F, 
 is much longer than the inner plate line 
 C, Z, D, more rafters will be required so 
 as to form a sufficient support for the 
 roof boards and covering. For this rea- 
 son an extra rafter from the plate line 
 A, X, F, to the ridge B, K, I, E, must 
 
 FIG. 73. 
 
ROOF FRAMING MADE EASY. 
 
 be inserted bet ween each abutting rafter 
 so as to equalize the spacing and obtain 
 a stable roof. 
 
 The proper way to find the shape of 
 the roof boards is seen at the bottom 
 side of Fig. 74. Divide D, H, into 10 
 equal parts, or more if desired, then with 
 O. as centre and O. l,as radius, describe 
 a curve, similarly describe from D. 
 2, :'.. 4 .I. I). 7. 8. 9 and 10. which will 
 of course bring the boards up to the 
 
 FIG. T4, 
 
 ridge line. Now take the distance from 
 E to I and set it off from H to P, the 
 centre of the rafter at I. and this will 
 give the lengths of boards for one sec- 
 tion. A like method can be followed 
 tor covering the outride slope of the 
 roof. This roof is of a very rare kind 
 and is only found on railroads where 
 locomotives are stored or on large estates 
 for barns or outhouses. 
 
 CHAPTER XXVII. 
 
 FRAMING A CANTILEVER ROOF. 
 
 T N answer to a letter requesting me to 
 
 illustrate and describe a cantilever 
 
 1 roof. I submit for the benefit of all 
 
 students of carpentry the following 
 
 design for a roof of this description, 
 
 which will be adaptable either for a 
 
 large shed or station. 
 
 The engraving, Fig 75, shows a 
 a transverse or cross section of the shed, 
 which may beany length desiied, the 
 width (covered) shown is 48' 0". at a 
 sca'e of i inch = 1 foot. If the width 
 
 be reduced half, timbers half the width 
 and thickness given here will be sum' 
 cient The height to under side of 
 straining beam is 13' 0", to ridge 2ti ? 6". 
 The construction of this building is very 
 simple and is fully illustrated by the 
 drawing. It consists of a series of con- 
 crete footings about 3 feet or 4 feet 
 square, placed on sand or hard clay 24' 
 0" apart, measuring from centre to cen- 
 tre across; and 10' 0" apart, measuring 
 from centre to centre, 
 longitudinally or length- 
 ways. On top of these 
 footings is set a good blue 
 or gianite stone mortised 
 out to receive the bottom 
 ends of the posts or up- 
 rights. These del ai Is con - 
 stitute the foundation. 
 
 The frame superstruc- 
 ture primarily consists of 
 the series of 10"xlO ' yel- 
 low pine square posts, 
 which are tenoned at top 
 and bottom ends, at the 
 bottom to fit into the hot 
 torn stone and at the top 
 to receive the 10" x 10" 
 stringer beam or plate A . 
 This longitudinal plate 
 or stringer is mortised to 
 receive the top ends of 
 the posts and the top 
 ends of the diagonal 
 braces H, which stiffen 
 the whole structure 
 lengthways. When con 
 structing this shed the posts, braces 
 and stringers should first be framed, 
 put together, raised and temporarily 
 braced across before commencing to 
 frame the truss roof. 
 
 Before commencing the latter a close 
 study should be made of the different 
 constructive details of the roof and the 
 lengths and forms carefully noted and 
 studied out in order not to spoil any of 
 the timber. 
 
 The first important detail is the 
 straining beam B This stick should be 
 procured 50' 0" long, laid out and 
 wrought as follows: First, the proper 
 position of the stringers A. 24'0"between 
 centres is laid out on the underside, also 
 laid out and gained for the braces D. 
 Then directly in the centre of this dis- 
 tance on the top side of the beam, the 
 position of the king tie C, is laid off and 
 distinctly marked. Directly over the 
 position of the stringers a mortise to re- 
 ceive the short 6" x 10" posts F is made 
 on both ends, also the opposite ends are 
 notched or gained out for the feet of 
 the principal rafters E. in the manner 
 shown, about 2" down in the beam. 
 
50 
 
 ROOF FRAMING MADE EASY 
 
ROOF FRAMING MADE EASY. 
 
 51 
 
 I 
 
 en 
 W 
 
52 
 
 ROOF FRAMING MADE EASY. 
 
 Next the principal rafters G, are mor- 
 tised out for the short posts, cut to the 
 exact length as given, to the top bevel 
 and notch required to fit into the strain- 
 ing beatn. It is also bored out for the 
 wrought iron rods and bolts G. delin- 
 eated. The straining beams are like- 
 wise bored for these irons. The short 
 posts F, and braces D are finally framed 
 with the usual tenons and the trusts is 
 ready to be put together . 
 
 In doing this the proper way to pro- 
 ceed is to first set the straining beam B. 
 then to insert the tenons of the short 
 posts F, into their mortises, next the 
 king tie C, and finally the principal 
 rafters E. The vertical bolts I, and 
 washers are next inserted andthe straps 
 J put on. This operation must of course 
 be gone through on each truss, and the 
 whole number finished before commenc- 
 ing to raise them into their permanent 
 position on top of the stringer beams 
 A A. The raising can be done with a 
 good gi^n pole or derrick. When the 
 trusses are set vertically on stringers 
 AA, to form the appearance seen in the 
 engraving, directly over the posts be- 
 low, each one should be well braced 
 with 2" x 4" joists to prevent it from be- 
 ing blown or knocked down. Each 
 truss should also be set perfectly plumb 
 sideways. If desired, the outer braces 
 KK may be omitted and the wrought 
 iron rod G inserted to counterbalance 
 the overhanging portion of the roof. 
 The space inside the braces may also be 
 filled in with ornamental scroll work, 
 either in iron or wood. In regard 
 to the strains on the different timbers 
 I would say that the straining beam 
 B is in tension, the braces K and D 
 underneath to the posts are in com- 
 pression. The principal rafters are in 
 compression. The king tie C is in 
 compression and the purlins bear a 
 lateral strain across the fibres. The 
 bolts are wrought iron. The washers 
 and plates cast iron Straps .are of 
 wrought iron |" x 2". This roof may 
 be safely covered with shingles, or 
 metal shingles, or tar paper. 
 
 It will be noticed that I have given in 
 this description a full written and de- 
 tailed description of the construction of 
 this roof and ''mode of procedure" 
 necessary to be followed in building it. 
 The years which I have studied con- 
 struction have taught me that much 
 detailed information is never superfluous 
 in conveying accurate mechanical prac- 
 tice to others. 
 
 The truss illustrated at Fig. 76 was 
 designed by Walter P. Rice, C. E.. 
 of Cleveland, Ohio, for the roof of the 
 grand stand at the baseball park in 
 that city, and reflects great credit on 
 him for the economical manner in 
 which he disposed of the constructive 
 details in such a way as to leave a view 
 of the field unobstructed. As will be 
 seen on reference to the plan the portion 
 of the roof where the cantilevers were 
 employed covered the portion on the 
 corners which was contained in the two 
 sides placed at right angles, and had a 
 post been placed under each truss the 
 view of the field would have been much 
 intercepted To avoid this he suspended 
 the intervening trusses shown by the 
 dotted lines on the plan on iron rods 
 which were carried over those trusses 
 resting on the posts, thus leaving the 
 space below clear for the spectators to 
 see the players. These trusses are but 
 slightly different in form from those in 
 ordinary roofs, though the static con- 
 ditions are changed on account of the 
 cantilever form. The drawing will ex 
 plain to readers its form and show how 
 judiciously and economically the pieces 
 were proportioned, also how the engi- 
 neer, realizing by calculation that the 
 greater part of the vertical strain would 
 necessarily be exerted on the front col 
 umns, increased its efficiency by using 
 an iron post of the diagonal lattice pat- 
 tern of the proportions shown. The 
 idea is an excellent one and worthy of 
 the high reputation of its designer. It 
 need scarcely be added that the entire 
 workmanship of the whole construction 
 of the stand, mostly timber, was done in 
 the most creditable manner. 
 
> lv 3v# **A f* 
 
 H 
 
 
 UNIVERSITY OF CALIFORNIA LIBRARY, 
 BERKELEY 
 
 
 THIS BOOK IS DUE ON THE LAST DATE 
 STAMPED BELOW 
 
 Books not returned on time are subject to a fine of 
 50c per volume after the third day overdue, increasing 
 to $1.00 per volume after the sixth day. Books not in 
 demand may be renewed if application is made before 
 expiration of loan period. 
 
 
 
 
 
 
YC 13059 
 
 
 
 cfr .** 5^ ^. *SK 
 
 
 %?*JW 
 
 UNIVERSITY OF CAlJFORNIA UBRARY 
 
 IF*. 
 
 '*.* 
 
 
 
 , , ^V'^ ^ 
 
 ^ 
 
 .f^,^^. 
 
 , ^*