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12 × 8 shed plan.

A free 12 × 8 ft lean-to shed plan: 3 × 4x6 skids, 2x6 @ 16 in o.c. floor joists, 2x4 @ 16 in o.c. studs and 2x8 @ 24 in o.c. rafters, about $3,404 in materials at estimated big-box prices. Blueprint, 3D model, materials list, code check and build steps.

12 × 8 ft lean-to shed

Framing
Skids3 × 4x6
Joists2x6 @ 16 in o.c.
Wall studs2x4 @ 16 in o.c.
Rafters2x8 @ 24 in o.c.

Estimated big-box prices (USD)before tax

Materials$3,403.90

A 12 × 8 ft shed on skids with a 3/12 lean-to roof, 96 sq ft of floor. 31 items in the list below, every one with its quantity and why.

Open this plan in 16Span: change it, price it at your store (free account)

Where these numbers come from. The floor, walls and roof are sized from the IRC 2021 tables and computed spans for No. 2 lumber, at the snow load the plan states. Those table values are still being checked line by line against the code book. Many towns need no permit for a small shed, but the size limit varies: check with your building department before you build.

013D model

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02Blueprint

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03Materials list

QtyItemEachTotal
Lumber$577.42
10 each2 in. x 6 in. x 8 ft. #2 Prime Ground Contact Pressure-Treated Lumber2 rim joists at 8'-0", 8 joists at 7'-9" → 2 boards cut 8'-0"; 8 boards cut 7'-9" (2'-0" total offcut).$8.48$84.80
2 each2 in. x 6 in. x 12 ft. #2 Prime Ground Contact Pressure-Treated Lumber2 rim joists at 12'-0" → 2 boards cut 12'-0" (0" total offcut).$12.98$25.96
3 each4 in. x 6 in. x 12 ft. #2 Ground Contact Pressure-Treated Timber3 skids at 12'-0" → 3 boards cut 12'-0" (0" total offcut).$38.40$115.20
32 each2 in. x 4 in. x 8 ft. #2 & Better Kiln-Dried SPF Lumber2 studs at 7'-11.25", 4 plates at 7'-7.75", 2 studs at 7'-7.25", 2 plates at 7'-5", 2 studs at 7'-3.25", 2 studs at 6'-11.25", 2 studs at 6'-9", 2 studs at 6'-7.25", 2 studs at 6'-4.25", 12 studs at 6'-3.5" → 2 boards cut 7'-11.25"; 4 boards cut 7'-7.75"; 2 boards cut 7'-7.25"; 2 boards cut 7'-5"; 2 boards cut 7'-3.25"; 2 boards cut 6'-11.25"; 2 boards cut 6'-9"; 2 boards cut 6'-7.25"; 2 boards cut 6'-4.25"; 12 boards cut 6'-3.5" (36'-2.25" total offcut).$3.98$127.36
15 each2 in. x 4 in. x 10 ft. #2 & Better Kiln-Dried SPF Lumber12 studs at 8'-2.75", 2 studs at 1'-0.25", 2 studs at 8'-2.25", 2 plates at 4'-5" → 2 boards cut 8'-2.75" + 1'-0.25"; 10 boards cut 8'-2.75"; 2 boards cut 8'-2.25"; 1 board cut 4'-5" + 4'-5" (24'-1.5" total offcut).$5.48$82.20
5 each2 in. x 4 in. x 12 ft. #2 & Better Kiln-Dried SPF Lumber5 plates at 12'-0" → 5 boards cut 12'-0" (0" total offcut).$6.78$33.90
1 each2 in. x 6 in. x 8 ft. #2 & Better Kiln-Dried SPF Lumber2 headers at 3'-5" → 1 board cut 3'-5" + 3'-5" (1'-2" total offcut).$6.48$6.48
9 each2 in. x 8 in. x 10 ft. #2 & Better Kiln-Dried SPF Lumber9 rafters at 9'-7.5" → 9 boards cut 9'-7.5" (3'-5" total offcut).$11.28$101.52
Hardware$12.32
14 eachSimpson Strong-Tie H2.5A ZMAX Hurricane TieOne per rafter at each wall it crosses against uplift: 7 × 2 = 14.$0.88$12.32
Fasteners$244.76
2 eachSubfloor Construction Adhesive (28 oz.)About one tube per 3 sheets glued to the joists: 4 sheets → 2.$9.98$19.96
4 box2-1/2 in. Stainless Steel Siding Nails (1 lb box)About 1 lb per 100 sq ft of siding: 333 sq ft → 4.$17.98$71.92
1 box1-1/2 in. Metal Roofing Screws with Washers (250-pack)About 1 screw per sq ft of panel: 125 sq ft → 1.$39.98$39.98
1 box8d 2-3/8 in. Ring Shank Sheathing Nails (5 lb box)About 50 nails a sheet (6 in at edges, 12 in in the field), ~250 per lb: 16 wall and roof sheets → 1.$24.98$24.98
4 box3-1/4 in. Bright Common Framing Nails (5 lb box)About 10 nails a framing piece (77), ~45 per lb = 18 lb → 4.$21.98$87.92
Foundation$110.00
2 cu. yd.Crushed Gravel 3/4 in., Bulk (cu. yd.)46.7 cu ft under the skids, + 10% for compaction = 1.9 cu yd → 2 (from a landscape supplier).$55.00$110.00
Sheathing$406.70
4 each23/32 in. x 4 ft. x 8 ft. Tongue and Groove Plywood Subfloor96 sq ft of floor ÷ 32 sq ft per sheet + 10% for cuts = 4.$54.98$219.92
11 each7/16 in. x 4 ft. x 8 ft. OSB Sheathing4 walls, 303 sq ft less openings ÷ 32 sq ft + 15% for gables and openings = 11.$16.98$186.78
Siding & trim$1,314.92
1 roll9 ft. x 100 ft. House Wrap303 sq ft of wall + 10% for laps ÷ 900 sq ft = 1.$159.00$159.00
1 roll1-7/8 in. x 165 ft. House Wrap TapeSeams, laps and openings.$14.98$14.98
42 each3/8 in. x 8 in. x 16 ft. Engineered Wood Lap Siding303 sq ft of wall less openings + 10% ÷ (6 in exposure × 16 ft = 8.0 sq ft a piece) = 42.$21.98$923.16
3 each1 in. x 4 in. x 12 ft. Primed Exterior Trim Board11 corner board and casing pieces (82'-11.25" in all), packed onto boards: 3 at 12 ft.$14.98$44.94
4 each1 in. x 4 in. x 16 ft. Primed Exterior Trim Board11 corner board and casing pieces (82'-11.25" in all), packed onto boards: 4 at 16 ft.$19.98$79.92
2 each1 in. x 6 in. x 16 ft. Primed Exterior Fascia Board2 fascia runs (26'-0"), packed onto boards: 2 at 16 ft.$27.98$55.96
1 roll4 in. x 75 ft. Self-Adhered Window and Door Flashing TapeSill pans and jambs at 1 opening.$29.98$29.98
1 each10 ft. Vinyl Drip Cap FlashingOver each opening's head casing: 4 ft ÷ 10 ft = 1.$6.98$6.98
Doors & windows$328.98
1 eachPre-Hung Exterior Door 36 in. x 80 in.The DOOR-1 unit; its opening is framed 38 x 82.5 in to suit it.$279.00$279.00
1 eachExterior Keyed Entry Door Knob and Deadbolt ComboLockset for DOOR-1.$49.98$49.98
Roofing$408.80
5 each1/2 in. x 4 ft. x 8 ft. OSB Roof Sheathing1 roof plane, 125 sq ft on the slope ÷ 32 sq ft + 10% = 5.$19.98$99.90
1 rollSynthetic Roofing Underlayment (10 sq. roll)125 sq ft + 10% for laps ÷ 1000 sq ft = 1.$89.00$89.00
5 each10 ft. Galvanized Steel Drip Edge45 ft of eaves and rakes, 10 ft pieces lapped 6 in = 5.$8.98$44.90
50 lin. ft.29-Gauge Galvalume Metal Roof Panel (36 in. coverage)5 panels at 36 in coverage, each cut to its plane's slope: 50 lin ft.$3.50$175.00
Estimated total, before tax$3,403.90

Prices are illustrative big-box estimates in US dollars, not a quote. Open the plan in 16Span to look up prices at your own store.

04Code check

Code check · not specified

What the rules say

  • N/A
    Stairs
    No stair is included. A 0 ft 11.75 in drop would need 2 risers of at most 7.75 in (IRC 2021 R311.7.5).
  • OK
    Joist cantilever
    Joists cantilever 0 ft 0.25 in past the beam. IRC 2021 R507.6 limits the cantilever to the lesser of 1/4 of the 3 ft 10.25 in back span (0 ft 11.5 in) and the table value — 0 ft 11.5 in. OK, 0 ft 11.25 in margin. (table values not yet verified against the code book)
  • Verify
    Span tables
    Joist, beam, post, footing and ledger values come from tables modeled on AWC DCA 6 and IRC 2021 R507 that have not yet been verified against the code book. Have the building department or a design professional confirm the member sizes before building.
  • Action
    Roof snow load
    No ground snow load was found for this site, so the roof is checked at 70 psf: an assumption, not the site's value. Confirm the ground snow load with the building department or the code's climate tables before buying lumber; a heavier load may need bigger rafters or headers.
  • OK
    Uplift
    Every rafter is tied down to its wall plate with a hurricane tie (IRC 2021 R802.11).
  • Verify
    Permit size
    This shed is 96 sq ft. Many places exempt small one-storey accessory buildings from a building permit: the IRC's model exemption (R105.2) is 200 sq ft, and Ontario's is 10 m² (about 108 sq ft). Your municipality sets its own limit, setbacks and height rules: check before you build.
  • Verify
    Foundation and frost
    The shed floats on skids on a gravel pad: nothing goes below the frost line, so it rises and settles a little with the frost each year, which a free-standing shed tolerates. No frost depth was found for this site. Re-level it in spring if a door starts to bind, never fasten it to the house or a fence, and confirm the building department accepts a floating foundation for an accessory building.
  • Verify
    Wind and uplift
    No design wind was found for this site. A shed on skids on a gravel pad is held down only by its own weight: where storms come through, and wherever the building department or an insurer asks for it, add ground anchors.
Structure

Every size, checked

RoleSizeSpecies / gradeSpan / loadChecked against
Joists2x6 @ 16 in o.c.Southern Pine #2, pressure-treated3 ft 10.25 in beam-to-beam + 0 ft 0.25 in cantileverIRC 2021 Table R507.6: 2x6 Southern Pine @ 16 in allows 9 ft 0 in; design spans 3 ft 10.25 in — OK, 5 ft 1.75 in margin. (table values not yet verified against the code book)
Skids3 × 4x6Ground-contact pressure-treated (AWPA UC4A)bear on grade along their length; the floor joists span between themNo span table applies: each skid bears continuously on a level, compacted gravel pad. The joist row above checks the span between skids.
Rafters2x8 @ 24 in o.c.Southern Pine #2, kiln-dried (under cover)8 ft 0 in horizontal, wall to wall, 3/12Computed span (AWC NDS 2018 No. 2 values, roof snow = ground snow, 10 psf dead): 2x8 Southern Pine @ 24 in, 70 psf ground snow, allows 8 ft 2 in; this roof spans 8 ft 0 in — OK, 0 ft 2 in to spare (table values not yet verified against the code book)
Wall studs2x4 @ 16 in o.c.Southern Pine #2, kiln-dried (under cover)tallest 8 ft 2.75 inIRC 2021 Table R602.3(5): 2x4 bearing studs carrying a roof may be 10 ft 0 in tall between supports; the tallest is 8 ft 2.75 in — OK (table values not yet verified against the code book)
Header DOOR-12-2x6Southern Pine #2, kiln-dried (under cover)3 ft 2 in rough openingComputed span (AWC NDS 2018 No. 2 values, roof snow = ground snow, 10 psf dead): 2-2x6 for a 8 ft wide building at 70 psf allows 5 ft 4 in with 1 jack stud a side; this opening is 3 ft 2 in — OK (table values not yet verified against the code book)

Assumptions

  • Sized for a 12 × 8 ft shed on 4x6 skids at an assumed snow load, with no snow load looked up for the site.
  • No location was given, so the local code, frost depth and permit rules are not looked up: confirm them with your building department.

Discrepancies flagged

None — the numbers close.

Code and structural values are AI-generated from published tables and can be wrong or out of date. Confirm anything marked “Verify” with your local building department before you dig. Read the safety disclaimer.

Build steps

Build steps

In this order

Each phase builds on the one before, so there is always something solid to fix to.

  1. 01

    1. Gravel pad and skids

    The skids carry the whole shed, so they must sit level on a firm, draining base.

    1. Strip the sod over the footprint plus 12 in all round, and lay 4 in of compacted crushed gravel, level within 1/4 in (check with a long straightedge and level).
    2. Set the 3 4x6 ground-contact skids on the pad where the plan shows them, parallel and level with each other.
  2. 02

    2. Floor frame

    The floor is the base the walls are laid out on: it must be square.

    1. Build the rim around the outline and fill it with 8 2x6 joists at 16 in o.c., crowns up, nailed through the rims.
    2. Square the frame (equal diagonals), then toe-nail or strap each joist to every skid it crosses.
  3. 03

    3. Floor sheathing

    The subfloor ties the frame together and is the deck the walls are built on.

    1. Glue and nail 23/32 in tongue-and-groove plywood across the joists, joints staggered and landing on joists; 8d ring-shank nails at 6 in on edges, 12 in in the field.
  4. 04

    4. Walls

    Walls are framed flat on the floor, then stood up: square, plumb and braced before the roof goes on.

    1. Snap the wall lines on the floor and cut the plates; lay out studs at 16 in o.c. from one corner, the same layout on the bottom and top plates.
    2. Frame each wall flat: 2x4 studs (the side walls' studs cut to the slope under their sloped plates) between a single bottom plate and the first top plate, three studs at each corner; at each of the 1 opening, king and jack studs, a 2-ply header on edge and cripples.
    3. Stand each wall up, nail its bottom plate through the floor into the joists, plumb it both ways and brace it; nail the corners together.
    4. Add the second top plate.
  5. 05

    5. Roof framing

    The roof frame has to be complete and tied down before sheathing stiffens it.

    1. Cut 7 2x8 rafters from a pattern rafter at 3/12, with a birdsmouth over each wall and the tails cut plumb; set them at 24 in o.c.
    2. Fasten a hurricane tie at every rafter where it crosses a plate.
  6. 06

    6. Sheathing

    Sheathing braces the walls and roof and is the base for everything weather-tight.

    1. Sheathe the walls with 7/16 in OSB, vertical, from the floor framing up, nailed at 6 in on edges and 12 in in the field; cut the openings out after.
    2. Sheathe the roof with 1/2 in OSB, long edges across the rafters, joints staggered, with 1/8 in gaps; nail the fascia to the rafter tails.
  7. 07

    7. Roofing

    Get the roof dry before the walls are finished.

    1. Drip edge on the eaves, synthetic underlayment lapped down-slope, then drip edge on the rakes.
    2. Screw the metal panels from one end, square to the eave, lapping one rib; then the ridge cap.
  8. 08

    8. Wrap, door and windows

    Openings are flashed before the units go in, so water drains out, not in.

    1. Wrap the walls in house wrap, lapped shingle-fashion (upper over lower), seams taped; cut the openings in an I pattern and fold the flaps in.
    2. Flash each sill and jamb with flashing tape, then set the pre-hung door: shim plumb and level, fasten, and tape the head flange over the wrap.
  9. 09

    9. Siding and trim

    The siding is the weather face: trim first, then courses up from a level line.

    1. Nail the corner boards and the casing round each opening, with drip cap flashing over each head.
    2. Snap a level line for the first course and run the engineered wood lap siding up at 6 in exposure, butting it to the trim; caulk the joints at the trim, and paint or stain to the maker's instructions.

05What this plan assumes

  • Sized for a 12 × 8 ft shed on 4x6 skids at an assumed snow load, with no snow load looked up for the site.
  • No location was given, so the local code, frost depth and permit rules are not looked up: confirm them with your building department.
Make it yours

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Open this plan in 16Span and ask for changes in plain words, like "make it 2 ft deeper" or "add stairs on the left". The structure is checked again, and the materials and price follow.

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