12x20 gable shed
Every board for this shed counted, cut and priced before you drive to the lumberyard. The whole plan is on this page. The full plan set to take to the yard is $19.
- Floor
- 240 sq ft
- Wall height
- 8' 1-1/8"
- Height from ground
- 12' 1-1/4"
- Rafters
- 32 x 2x4
- Materials
- $4,691
The list you take to the lumberyard
Every board, sheet and box of nails, packed into the stock lengths the store sells, so nothing is a guess at the counter.
- Lumber
- $1,184
- Sheet goods
- $2,057
- Hardware and finish
- $1,450
- 6PT 4x6 x 10 ft$161.88
- 4PT 2x6 x 10 ft$47.92
- 16PT 2x6 x 12 ft$231.68
- 502x4 x 92-5/8" precut stud$205
- 472x4 x 8 ft$204.45
- 82x4 x 10 ft$51.84
- 122x4 x 12 ft$95.76
- 22x6 x 8 ft$14.96
- 22x6 x 12 ft$23.96
- 4PT 2x4 x 10 ft$31.92
- 2PT 2x4 x 12 ft$19.36
- 41x4 x 10 ft$25.92
- 41x6 x 8 ft$27.92
- 41x6 x 12 ft$41.92
- 9T&G plywood 3/4" 4x8$530.82
- 12OSB 7/16" 4x8$203.76
- 21T1-11 siding 5/8" 4x8$1,322.58
- 11Shingles (bundle, 33.3 sq ft)$406.78
- 1Synthetic underlayment (roll, 400 sq ft)$89
- 8Drip edge 10 ft$75.84
- 2Ridge cap shingles (bundle, ~20 lin ft)$116
- 5Framing nails 16d (5 lb box)$124.90
- 4Siding nails 8d galvanized (5 lb box)$111.92
- 2Roofing nails 1-1/4" (5 lb box)$43.96
- 32Hurricane ties H2.5A$31.36
- 3Heavy strap hinges 8" (pair)$56.94
- 1Gate latch / hasp$12.98
- 4Gravel 3/4" crushed (cubic yard, bulk)$220
- 4Exterior paint or stain (1 gal)$159.92
Typical Home Depot and Lowe's shelf prices, October 2026. Your store will differ by a few percent.
The drawings
Framing drawn from the same boards the list counts. Hover a member to see what it is.
Cut list
Every piece, how many, and how long. Tape it to the saw.
| Qty | Board | Cut to | Part |
|---|---|---|---|
| 16 | PT 2x6 | 11' 9" | Floor joist16" on center |
| 6 | PT 4x6 | 10' 0" | Skidpressure treated, sits on gravel |
| 4 | PT 2x6 | 10' 0" | Rim joistside band of the floor frame |
| Qty | Board | Cut to | Part |
|---|---|---|---|
| 2 | PT 2x4 | 12' 0" | Bottom platepressure treated, nailed to the deck |
| 2 | 2x4 | 12' 0" | Top platefirst layer |
| 2 | 2x4 | 11' 5" | Top platesecond layer, between the side plates |
| 4 | 2x4 | 10' 0" | Top platesecond layer, laps the corners |
| 4 | PT 2x4 | 9' 8-1/2" | Bottom platepressure treated, nailed to the deck |
| 4 | 2x4 | 9' 8-1/2" | Top platefirst layer |
| 48 | 2x4 | 7' 8-5/8" | Stud16" on center |
| 2 | 2x4 | 7' 8-5/8" | King studfull height beside the door opening |
| 2 | 2x4 | 6' 3-1/2" | Jack studcarries the header, rough opening 77" tall |
| 2 | 2x6 | 5' 5" | Header plytwo plies with 1/2" plywood between, on edge |
| 4 | 2x4 | 11-5/8" | Cripple studabove the header, on layout |
| Qty | Board | Cut to | Part |
|---|---|---|---|
| 8 | 2x4 | 12' 0" | Rafter tienailed to both rafters of a pair at the plate |
| 2 | 2x6 | 10' 6" | Ridge boardtop flush with the rafter tops |
| 32 | 2x4 | 7' 9-1/8" | Rafterplumb cuts at 26.6°, birdsmouth seat 2-3/8" |
| 4 | 2x4 | 7' 9-1/8" | Barge rafterfly rafter on the gable overhang, no birdsmouth |
| 4 | 2x4 | 2' 5-1/2" | Gable studlong point, top cut at 26.6° |
| 4 | 2x4 | 1' 9-1/2" | Gable studlong point, top cut at 26.6° |
| 4 | 2x4 | 1' 1-1/2" | Gable studlong point, top cut at 26.6° |
| Qty | Board | Cut to | Part |
|---|---|---|---|
| 4 | 2x4 | 6' 4" | Door stiledoor frame, laid flat |
| 6 | 2x4 | 1' 11-1/4" | Door raildoor frame, between the stiles |
| Qty | Board | Cut to | Part |
|---|---|---|---|
| 4 | 1x6 | 10' 6" | Fasciaeave fascia on the rafter tails |
| 4 | 1x4 | 8' 7-3/8" | Corner boardoutside corners over the siding |
| 4 | 1x6 | 7' 9-7/8" | Rake boardalong the gable overhang |
Which piece comes from which board
165 boards, laid out so the offcuts stay small.
Build it in this order
- 01
Check the rules first
Ask your town about permits and setbacks before you buy lumber. Many towns allow a shed of up to 120 to 200 sq ft without a permit, but rules and HOA covenants vary.
- 02
Make the gravel pad
Dig out sod for a pad 1 ft wider than the shed on every side (14 x 22 ft), fill with about 4 cubic yards of 3/4" crushed gravel 4" deep, and level it.
- 03
Set the skids
Lay the 3 PT 4x6 skids along the depth, evenly spaced, and level them to each other. Shim with solid blocks, never with stacked scraps.
- 04
Frame the floor
Nail the two rim joists to the ends of the 16 floor joists at 16" on center. Check square: the two diagonals must be equal. Toe-screw the frame to the skids.
- 05
Sheath the deck
Glue and screw the 9 sheets of 3/4" tongue-and-groove plywood, long edges across the joists, joints staggered.
- 06
Build the back wall
Frame it flat on the deck: bottom plate, 92-5/8" precut studs at 16" on center, first top plate. Raise it, plumb it, brace it.
- 07
Build the front wall
Same layout with the double doors, 5 ft opening opening: king studs full height, jack studs carrying the 2x6 header, cripples above. Rough opening 62" wide and 77" tall.
- 08
Build the side walls
Fit them between the front and back walls, then nail the corners. Add the second top plate so it laps every corner.
- 09
Cut a pattern rafter
Mark the ridge plumb cut at 26.6°, measure 7' 9-1/8" along the top edge to the tail, and cut the birdsmouth with a 2-3/8" seat. Test it at both ends of the shed before you cut the rest.
- 10
Raise the ridge and rafters
Set the end rafter pairs with the 2x6 ridge between them, then fill in the rest at 16" on center. Nail a rafter tie across every other pair at the plates and add a hurricane tie at each rafter.
- 11
Frame the gable ends
Cut the gable studs to their lengths from the cut list (top cut at the roof angle) and set them on layout under the end rafters.
- 12
Sheath and roof
Nail on 12 sheets of 7/16" OSB, then drip edge at the eaves, underlayment, drip edge on the rakes, and shingles from the bottom up.
- 13
Side it and hang the doors
Nail on the 21 sheets of T1-11 (they also skin the doors). Build the door frames flat, skin them, and hang them on strap hinges. Trim the corners and the fascia.
- 14
Finish
Prime and paint or stain every cut edge and the siding. Build a short ramp if you will roll a mower in.
- Every drawing at full page size, dimensions on every member
- The cut list on one page, grouped the way you build
- The cutting diagram for every board
- The materials list ready to hand to the lumberyard or load into a store cart
- The build steps with a check at the end of each
- Your exact size, not the nearest one we had
Before you dig
Do I need a permit for this shed?
240 sq ft. Many towns exempt sheds of 120 sq ft or less (some go to 200), as long as they meet setbacks from the property line. Electricity, plumbing or living space always needs a permit. Call your building department or check the town website before you buy lumber; HOA rules are separate and often stricter.
Is it cheaper to build this or buy a kit?
The lumber and materials for this plan come to about $4,691 at big-box prices. Wood kits of the same size usually cost more and use thinner framing; resin and metal kits cost less but are not the same building. Building from scratch pays when you want 2x4 walls 16 in on center, a real floor and a roof that carries snow.
What foundation does it sit on?
3 pressure-treated 4x6 skids on a 4 in crushed-gravel pad, about 4 cubic yards. It drains, it stays level, and the shed can be moved later. Use concrete piers if your town requires an anchored foundation.
Will the roof hold snow?
This plan uses 2x4 rafters at 16 in on center for little or no snow (up to 20 psf). In a heavier snow area, switch the snow setting in the planner and it upsizes the rafters for you. When in doubt, ask your building department for the local ground snow load.
Can I change the door?
Yes. Set the door in the planner: the rough opening, header, king and jack studs update. This plan has double doors, 5 ft opening with a 62" wide rough opening.
How long does it take?
Most first-time builders frame and roof a shed this size over two to three weekends with a helper. Siding, doors, trim and paint take another weekend.