Timber roof trusses — materials
A rough list to take to a sawmill. The frame is cut green — full-sawn timbers straight from the log — and pinned with dry oak pegs: as the timbers dry they shrink onto the pegs, and the drawbored joints pull tighter. The mill cuts every stick to its section and length; the framer cuts the joints.
Each length is the piece’s cut length plus 10 in for tenons and trimming, rounded up to the foot. A piece longer than 24 ft is ordered in two or more lengths joined by a scarf (A2-16). Board feet are full-sawn: width × depth × feet ÷ 12. Sizes follow the model, which is proportioned from measured drawings, not engineered — a frame that will carry a load is sized by an engineer first.
King — span 240 in (20 ft), pitch 9/12
| Section (in) | Length (ft) | Pieces | Board feet | For |
|---|---|---|---|---|
| 6 × 12 | 24 | 1 | 144 | tie beam |
| 6 × 12 | 10 | 1 | 60 | king post |
| 6 × 10 | 14 | 2 | 140 | principal rafter L · principal rafter R |
| 4 × 6 | 7 | 2 | 28 | raking strut L · raking strut R |
372 board feet of green timber in 6 pieces.
Pegs: 5 of dry oak, 1 in by 8 in — order a tenth over.
Queen — span 360 in (30 ft), pitch 9/12
| Section (in) | Length (ft) | Pieces | Board feet | For |
|---|---|---|---|---|
| 6 × 12 | 19 | 2 | 228 | tie beam |
| 6 × 10 | 21 | 2 | 210 | principal rafter L · principal rafter R |
| 6 × 8 | 11 | 1 | 44 | straining beam |
| 6 × 8 | 9 | 2 | 72 | queen post L · queen post R |
| 4 × 6 | 7 | 2 | 28 | raking strut L · raking strut R |
582 board feet of green timber in 9 pieces.
1 member is longer than a 24 ft stick and is scarfed.
Pegs: 10 of dry oak, 1 in by 8 in — order a tenth over.
Scissor — span 240 in (20 ft), pitch 10/12
| Section (in) | Length (ft) | Pieces | Board feet | For |
|---|---|---|---|---|
| 6 × 10 | 15 | 2 | 150 | rafter L · rafter R |
| 6 × 8 | 16 | 2 | 128 | scissor brace L · scissor brace R |
| 6 × 6 | 3 | 2 | 18 | wall plate L (length shown) · wall plate R (length shown) |
296 board feet of green timber in 6 pieces.
Pegs: 8 of dry oak, 1 in by 8 in — order a tenth over.
Hammerbeam — span 288 in (24 ft), pitch 12/12
| Section (in) | Length (ft) | Pieces | Board feet | For |
|---|---|---|---|---|
| 6 × 12 | 9 | 2 | 108 | arch brace L (curved) · arch brace R (curved) |
| 6 × 10 | 19 | 2 | 190 | principal rafter L · principal rafter R |
| 6 × 8 | 16 | 1 | 64 | collar |
| 6 × 8 | 7 | 2 | 56 | hammer beam L · hammer beam R |
| 6 × 6 | 7 | 2 | 42 | wall post L · wall post R |
| 6 × 6 | 6 | 2 | 36 | hammer post L · hammer post R |
496 board feet of green timber in 11 pieces.
Pegs: 12 of dry oak, 1 in by 8 in — order a tenth over.
Cruck — span 216 in (18 ft), pitch 15/12
| Section (in) | Length (ft) | Pieces | Board feet | For |
|---|---|---|---|---|
| 6 × 12 | 18 | 2 | 216 | cruck blade L (curved) · cruck blade R (curved) |
| 6 × 8 | 11 | 1 | 44 | collar |
| 6 × 6 | 3 | 3 | 27 | ridge purlin (length shown) · sill L (length shown) · sill R (length shown) |
287 board feet of green timber in 6 pieces.
Pegs: 4 of dry oak, 1 in by 8 in — order a tenth over.
Arch-collar — span 240 in (20 ft), pitch 12/12
| Section (in) | Length (ft) | Pieces | Board feet | For |
|---|---|---|---|---|
| 6 × 12 | 13 | 2 | 156 | arch brace L (curved) · arch brace R (curved) |
| 6 × 10 | 16 | 2 | 160 | principal rafter L · principal rafter R |
| 6 × 8 | 11 | 1 | 44 | collar |
| 6 × 6 | 5 | 2 | 30 | wall post L · wall post R |
| 6 × 6 | 3 | 2 | 18 | wall plate L (length shown) · wall plate R (length shown) |
408 board feet of green timber in 9 pieces.
Pegs: 10 of dry oak, 1 in by 8 in — order a tenth over.
Not in this list: stone, brick and mortar; siding, trim, windows and doors; roofing; nails. Nothing here is priced.
Cut list, piece by piece
| Piece | Qty | Section (in) | Cut length (in) | Ends |
|---|---|---|---|---|
| king — span 240 in (20 ft), pitch 9/12: Tie beam | 1 | 6 × 12 | 277 3/8 | A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg · A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg |
| king — span 240 in (20 ft), pitch 9/12: Principal rafter L | 1 | 6 × 10 | 153 1/8 | foot: A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg · head: A6-24 joggle, plumb shoulder 5 1/2 in, tenon 3 in up the rafter axis, 1 peg; cut square to the axis at both ends, 36.9° |
| king — span 240 in (20 ft), pitch 9/12: Principal rafter R | 1 | 6 × 10 | 153 1/8 | foot: A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg · head: A6-24 joggle, plumb shoulder 5 1/2 in, tenon 3 in up the rafter axis, 1 peg; cut square to the axis at both ends, 36.9° |
| king — span 240 in (20 ft), pitch 9/12: King post | 1 | 6 × 12 | 103 1/2 | foot: A6-13 stub tenon 2 in into the tie, 1 peg · head: A6-24 jowled head, two joggles square to the principals |
| king — span 240 in (20 ft), pitch 9/12: Raking strut L | 1 | 4 × 6 | 67 1/2 | foot: A6-25 joggle on the post foot, face square to the strut, stub tenon 1 1/2 in · head: A6-25 housing 3/4 in under the principal, stub tenon; strut at 28.6°, no peg (compression only) |
| king — span 240 in (20 ft), pitch 9/12: Raking strut R | 1 | 4 × 6 | 67 1/2 | foot: A6-25 joggle on the post foot, face square to the strut, stub tenon 1 1/2 in · head: A6-25 housing 3/4 in under the principal, stub tenon; strut at 28.6°, no peg (compression only) |
| queen — span 360 in (30 ft), pitch 9/12: Tie beam | 1 | 6 × 12 | 397 3/8 | A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg · A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg |
| queen — span 360 in (30 ft), pitch 9/12: Principal rafter L | 1 | 6 × 10 | 235 1/4 | foot: A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg · head: A6-19 tongue-and-fork at the ridge, plumb cut, tongue 6 in, 1 peg; passes over the queen head A6-26 on a stub tenon; 36.9° |
| queen — span 360 in (30 ft), pitch 9/12: Principal rafter R | 1 | 6 × 10 | 235 1/4 | foot: A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg · head: A6-19 tongue-and-fork at the ridge, plumb cut, tongue 6 in, 1 peg; passes over the queen head A6-26 on a stub tenon; 36.9° |
| queen — span 360 in (30 ft), pitch 9/12: Queen post L | 1 | 6 × 8 | 94 | foot: A6-13 stub tenon into the tie, 1 peg · head: A6-26 jowled head cut to the slope, stub tenon up into the principal; straining beam tenon from the side, 1 peg |
| queen — span 360 in (30 ft), pitch 9/12: Queen post R | 1 | 6 × 8 | 94 | foot: A6-13 stub tenon into the tie, 1 peg · head: A6-26 jowled head cut to the slope, stub tenon up into the principal; straining beam tenon from the side, 1 peg |
| queen — span 360 in (30 ft), pitch 9/12: Straining beam | 1 | 6 × 8 | 120 1/2 | A6-26 tenon into the queen head, 1 peg · same |
| queen — span 360 in (30 ft), pitch 9/12: Raking strut L | 1 | 4 × 6 | 66 1/8 | foot: A6-25 joggle on the post foot, face square to the strut, stub tenon 1 1/2 in · head: A6-25 housing 3/4 in under the principal, stub tenon; strut at 31.3°, no peg (compression only) |
| queen — span 360 in (30 ft), pitch 9/12: Raking strut R | 1 | 4 × 6 | 66 1/8 | foot: A6-25 joggle on the post foot, face square to the strut, stub tenon 1 1/2 in · head: A6-25 housing 3/4 in under the principal, stub tenon; strut at 31.3°, no peg (compression only) |
| scissor — span 240 in (20 ft), pitch 10/12: Rafter L | 1 | 6 × 10 | 163 3/8 | foot: A6-20 birdsmouth 2 1/2 in over the wall plate, plumb tail at the plate's outer face · head: A6-19 tongue-and-fork, 1 peg; 39.8° |
| scissor — span 240 in (20 ft), pitch 10/12: Rafter R | 1 | 6 × 10 | 163 3/8 | foot: A6-20 birdsmouth 2 1/2 in over the wall plate, plumb tail at the plate's outer face · head: A6-19 tongue-and-fork, 1 peg; 39.8° |
| scissor — span 240 in (20 ft), pitch 10/12: Scissor brace L | 1 | 6 × 8 | 173 3/8 | lower end: A6-12 half-dovetail lap on the rafter face at the heel, 1 peg · upper end: A6-12 lap on the opposite rafter at 2/3 of its run, 1 peg; crossing at mid-span A2-04 halved, 1 peg; 22.6° |
| scissor — span 240 in (20 ft), pitch 10/12: Scissor brace R | 1 | 6 × 8 | 173 3/8 | lower end: A6-12 half-dovetail lap on the rafter face at the heel, 1 peg · upper end: A6-12 lap on the opposite rafter at 2/3 of its run, 1 peg; crossing at mid-span A2-04 halved, 1 peg; 22.6° |
| scissor — span 240 in (20 ft), pitch 10/12: Wall plate L (length shown) | 1 | 6 × 6 | 24 | A6-20 seat · — |
| scissor — span 240 in (20 ft), pitch 10/12: Wall plate R (length shown) | 1 | 6 × 6 | 24 | A6-20 seat · — |
| hammerbeam — span 288 in (24 ft), pitch 12/12: Wall post L | 1 | 6 × 6 | 73 1/2 | foot: on a stone corbel (A6-22 pier case; corbel not drawn) · head: A6-27 stub tenon up into the hammer beam |
| hammerbeam — span 288 in (24 ft), pitch 12/12: Wall post R | 1 | 6 × 6 | 73 1/2 | foot: on a stone corbel (A6-22 pier case; corbel not drawn) · head: A6-27 stub tenon up into the hammer beam |
| hammerbeam — span 288 in (24 ft), pitch 12/12: Hammer beam L | 1 | 6 × 8 | 72 | inner end: A6-27 mortise for the hammer post, brace tenon below · outer end: A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg for the principal |
| hammerbeam — span 288 in (24 ft), pitch 12/12: Hammer beam R | 1 | 6 × 8 | 72 | inner end: A6-27 mortise for the hammer post, brace tenon below · outer end: A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg for the principal |
| hammerbeam — span 288 in (24 ft), pitch 12/12: Hammer post L | 1 | 6 × 6 | 60 1/4 | foot: A6-13 stub tenon into the hammer beam · head: cut to the slope, stub tenon up into the principal (A6-26 idiom) |
| hammerbeam — span 288 in (24 ft), pitch 12/12: Hammer post R | 1 | 6 × 6 | 60 1/4 | foot: A6-13 stub tenon into the hammer beam · head: cut to the slope, stub tenon up into the principal (A6-26 idiom) |
| hammerbeam — span 288 in (24 ft), pitch 12/12: Principal rafter L | 1 | 6 × 10 | 213 1/2 | foot: A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg on the hammer beam · head: A6-19 tongue-and-fork, 1 peg; 45.0° |
| hammerbeam — span 288 in (24 ft), pitch 12/12: Principal rafter R | 1 | 6 × 10 | 213 1/2 | foot: A6-23 heel: toe abutment square to the rafter, level seat, tenon under the seat, 1 peg on the hammer beam · head: A6-19 tongue-and-fork, 1 peg; 45.0° |
| hammerbeam — span 288 in (24 ft), pitch 12/12: Collar | 1 | 6 × 8 | 177 1/8 | A6-12 half-dovetail lap on the principal, 1 peg · same |
| hammerbeam — span 288 in (24 ft), pitch 12/12: Arch brace L (curved) | 1 | 6 × 12 | 89 7/8 | foot: A6-03 brace tenon into the wall post, 1 peg · head: A6-03 tenon into the hammer beam underside, 1 peg |
| hammerbeam — span 288 in (24 ft), pitch 12/12: Arch brace R (curved) | 1 | 6 × 12 | 89 7/8 | foot: A6-03 brace tenon into the wall post, 1 peg · head: A6-03 tenon into the hammer beam underside, 1 peg |
| cruck — span 216 in (18 ft), pitch 15/12: Cruck blade L (curved) | 1 | 6 × 12 | 197 1/2 | foot: A6-22 stub tenon into the sill · apex: A6-28 crossed and halved, ridge in the crotch; collar A6-12 lap, 1 peg |
| cruck — span 216 in (18 ft), pitch 15/12: Cruck blade R (curved) | 1 | 6 × 12 | 197 1/2 | foot: A6-22 stub tenon into the sill · apex: A6-28 crossed and halved, ridge in the crotch; collar A6-12 lap, 1 peg |
| cruck — span 216 in (18 ft), pitch 15/12: Collar | 1 | 6 × 8 | 115 3/4 | A6-12 half-dovetail lap across the blade, 1 peg · same |
| cruck — span 216 in (18 ft), pitch 15/12: Ridge purlin (length shown) | 1 | 6 × 6 | 24 | A6-28 seated in the crotch, not fixed · — |
| cruck — span 216 in (18 ft), pitch 15/12: Sill L (length shown) | 1 | 6 × 6 | 24 | A6-22 mortise for the blade foot · — |
| cruck — span 216 in (18 ft), pitch 15/12: Sill R (length shown) | 1 | 6 × 6 | 24 | A6-22 mortise for the blade foot · — |
| arch-collar — span 240 in (20 ft), pitch 12/12: Principal rafter L | 1 | 6 × 10 | 181 3/4 | foot: A6-20 birdsmouth 2 1/2 in over the wall plate · head: A6-19 tongue-and-fork, 1 peg; 45.0° |
| arch-collar — span 240 in (20 ft), pitch 12/12: Principal rafter R | 1 | 6 × 10 | 181 3/4 | foot: A6-20 birdsmouth 2 1/2 in over the wall plate · head: A6-19 tongue-and-fork, 1 peg; 45.0° |
| arch-collar — span 240 in (20 ft), pitch 12/12: Wall post L | 1 | 6 × 6 | 47 | foot: on a corbel (A6-22 pier case; corbel not drawn) · head: cut to the slope, stub tenon up into the principal (A6-13 seat, inverted) |
| arch-collar — span 240 in (20 ft), pitch 12/12: Wall post R | 1 | 6 × 6 | 47 | foot: on a corbel (A6-22 pier case; corbel not drawn) · head: cut to the slope, stub tenon up into the principal (A6-13 seat, inverted) |
| arch-collar — span 240 in (20 ft), pitch 12/12: Collar | 1 | 6 × 8 | 121 1/8 | A6-12 half-dovetail lap on the principal, 1 peg · same |
| arch-collar — span 240 in (20 ft), pitch 12/12: Arch brace L (curved) | 1 | 6 × 12 | 136 | foot: A6-03 brace tenon into the wall post, 1 peg · head: A6-03 tenon into the collar underside, 1 peg |
| arch-collar — span 240 in (20 ft), pitch 12/12: Arch brace R (curved) | 1 | 6 × 12 | 136 | foot: A6-03 brace tenon into the wall post, 1 peg · head: A6-03 tenon into the collar underside, 1 peg |
| arch-collar — span 240 in (20 ft), pitch 12/12: Wall plate L (length shown) | 1 | 6 × 6 | 24 | A6-20 seat · — |
| arch-collar — span 240 in (20 ft), pitch 12/12: Wall plate R (length shown) | 1 | 6 × 6 | 24 | A6-20 seat · — |