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A 10×12 lean-to shed material list on skids comes to 50 2×4 framing boards, 12 2×6 x 12 ft rafter boards and 12 treated 2x6s. Sheets: 4 floor plywood, 6 OSB and 14 T1-11, plus 6 shingle bundles. That assumes an 80 in back wall, a 109 1/8 in front wall and a 3/12 roof.

Every number on this page comes from the 3DSHEDPLANS plan generator. It lays out each stud, rafter and sheet, checks that every sloped side stud meets the roof line, and counts what to buy by stock length. A single-slope roof has fewer parts than a gable, but each side wall has 9 studs of 9 different lengths. This list is for a freestanding shed, not one attached to a house.

What this 10×12 lean-to list assumes

The generator ran a shed 10 ft deep and 12 ft wide, with 120 sq ft of floor. The roof slopes front to back, so the 12 ft front wall with the door is the tall one. These are its settings:

  • Walls: the back (low) wall is 80 in tall and the front (high) wall is 109 1/8 in, both including the bottom plate and double top plate. Back studs are 6′ 3 1/2″ and front studs 8′ 8 5/8″.
  • Roof: 3/12 pitch (about 14 degrees), 2×6 rafters with a birdsmouth on both walls, 8 in overhangs front and back, 4 in rakes. The roof is about 152 in long by 140 in down the slope, roughly 148 sq ft.
  • Spacing: studs, floor joists and rafters at 16 in on center.
  • Floor: four pressure-treated 4×4 skids on a crushed stone pad, 2×6 joists across the 10 ft depth, 3/4 in tongue and groove plywood.
  • Loads: the 2×6 rafters span 113 in against a 143 in limit (SPF #2 at 16 in, 30 psf ground snow). In heavier snow country, check your local permit office for your snow load.
  • Openings: a 60 in double door in the front wall and one 36 x 36 in window in the back wall.

Shopping list by stage: the full 10×12 lean-to shed material list

Lumber sizes are nominal. A 2×4 measures about 1 1/2 x 3 1/2 in and a 2×6 about 1 1/2 x 5 1/2 in, as the American Wood Council explains. Check the grade stamp on plywood and OSB; the APA trademark guide shows how to read it.

Floor

Item Qty Used for
Pressure-treated 4×4 x 12 ft 4 Skids
Pressure-treated 2×6 x 12 ft 2 Rim joists
Pressure-treated 2×6 x 10 ft 10 Floor joists
3/4 in T&G plywood, 4×8 sheet 4 Floor decking
2×4 x 8 ft 2 Blocks under the flat decking seams
Crushed stone 3/4 in, loose 2.5 cu yd Gravel pad
Deck screws 2 in (or 6d ring-shank nails) 3 lb Decking

Walls

Item Qty Used for
2×4 x 8 ft 15 Shorter side-wall studs, back sill and lower cripples, front cripples, lookout blocks
2×4 x 10 ft 21 Front wall studs, taller side-wall studs, side-wall plates, sloped top plates
2×4 x 12 ft 7 Front and back wall plates and cap plates, back window trimmers
2×4 x 14 ft 7 Back wall studs (two per board), front door trimmers
2×8 x 12 ft 1 Door header
2×6 x 8 ft 2 Window header, some rafter blocking
Strap ties (twist straps) 4 Lean-to wall corners
Temporary braces 2×4 x 12 ft 8 Wall bracing, reused later
2×4 stakes, 24 in 8 Brace stakes, cut from offcuts

The two header filler strips of 1/2 in plywood are ripped from the soffit sheet, so buy that sheet with the wall lumber. With the 2 seam blocks and 8 braces, the truck carries 60 2x4s in all.

Roof

Item Qty Used for
2×6 x 12 ft 12 10 rafters and 2 fly rafters
2×6 x 10 ft 2 Blocking between rafters over each wall
Hurricane ties, H2.5A type or equal 20 Rafter to plate, both walls
7/16 in OSB, 4×8 sheet 6 Roof sheathing
15 lb felt, 400 sq ft roll 1 Underlayment, laid double below 4/12
3-tab shingles, 26 per bundle 6 bundles Roof and starter course
Drip edge, 10 ft 6 Eaves and rakes
Roofing nails 1 1/4 in galvanized 5 lb Shingles
Roofing cap nails 1 in 1 lb Felt
Roofing cement, 10 oz tube 2 Roofing

Siding and trim

Item Qty Used for
5/8 in T1-11, 4×10 sheet 3 Front (high) wall
5/8 in T1-11, 4×8 sheet 3 Back (low) wall
5/8 in T1-11, 4×10 / 4×9 / 4×8 sheet 2 / 2 / 2 Sloped side walls
5/8 in T1-11, 4×8 sheet 2 Door leaves (one per leaf)
1/2 in plywood, 4×8 sheet 1 Eave soffit and header fillers
1×8 x 14 ft 4 Eave and rake fascia
1×4 x 14 ft 6 Back corner trim, door casing sides, stiles, Z braces
1×4 x 12 ft 1 Door rails
1×4 x 10 ft 4 Front corner trim
1×4 x 8 ft 3 Door head casing, window casing
1×2 x 8 ft 2 Door stop and astragal
Drip cap, 10 ft 1 Over the door and window head casings
Insect screen, 2 ft x 25 ft 1 roll Gaps at the eaves and soffit
Exterior paint and primer in one 4 gal Two coats, about 499 sq ft each
Exterior caulk 3 tubes Trim

Hardware and window

Item Qty
Framing nails 3 1/2 in (16d), hot-dip galvanized 21 lb
Siding nails 2 1/2 in (8d), hot-dip galvanized 10 lb
Sheathing nails 2 1/2 in (8d) for OSB 5 lb
Connector nails 1 1/2 in for ties and straps 2 lb
Construction adhesive, 10 oz tube 3
T-strap door hinges 6
Door handle and latch set 1
Barrel bolts for the fixed leaf 2
Exterior screws 1 1/4 in (door frame to T1-11) 1 lb
Exterior screws 2 1/2 in (hinge straps into framing) 1 box
Prefabricated window, 36 x 36 in rough opening 1
Flashing tape 4 in 1 roll
Wood shims 1 bundle

Cut list highlights

Most of the 10×12 lean-to cut list is square cuts: 10 front studs at 8′ 8 5/8″, 12 back studs at 6′ 3 1/2″, 10 floor joists at 9′ 9″ and four skids at 12′ 0″. The parts below carry angles or a different length every time, so a layout error repeats or one wrong cut costs a board. Dry-fit the first of each part on your own frame before cutting the rest.

Part Lumber Cut length Qty
Rafter (board length) 2×6 11′ 9 1/2″ 10
Fly rafter (rake) 2×6 11′ 9 1/2″ 2
Side wall sloped top plate 2×4 9′ 8 1/2″ 2
Side wall bottom plate 2×4 9′ 4 7/8″ 2
Left wall studs 2×4 6′ 5 3/8″ to 8′ 9 1/4″ 9, all different
Right wall studs 2×4 8′ 9 1/4″ down to 6′ 5 3/8″ 9, all different
Door header (2×8 doubled + 1/2 ply) 2×8 5′ 3″ 2
Door trimmer 2×4 6′ 4 1/2″ 2
Cripple over the door 2×4 1′ 8 7/8″ 4
Window header (2×6 doubled + 1/2 ply) 2×6 3′ 3″ 2
Window trimmer 2×4 5′ 10″ 2
Blocking between rafters 2×6 1′ 1 3/4″ and 1′ 2 1/2″ 4 and 14
Lookout block (rake overhang) 2×4 2 1/2″ 14
Eave fascia 1×8 12′ 8″ 2
Rake fascia (tip to tip) 1×8 11′ 11 1/2″ 2

Rafters. The 11′ 9 1/2″ figure is the board each rafter needs, measured corner to corner. Along the top edge it is about 11′ 8 3/16″, including both 8 in overhangs. Plumb cuts are at about 14 degrees (3/12).

Each rafter gets two birdsmouths, one on each wall, with a 3 1/2 in seat that notches under 1 in into the 2×6, well inside the one-third rule. Cut one pattern rafter, test it on both walls, then trace the other 9. The 2 fly rafters sit on the lookout blocks and get no birdsmouth.

Side wall studs. Each side wall has 9 studs under a sloped top plate. The steps are 4 in except at the ends: 2 7/8 in and 1 in on the left wall, 3 in and 7/8 in on the right. Every length is the long point, from the top of the bottom plate to the underside of the sloped plate. The left wall, listed from the back corner, runs 6′ 5 3/8″, 6′ 8 1/4″, 7′ 0 1/4″, 7′ 4 1/4″, 7′ 8 1/4″, 8′ 0 1/4″, 8′ 4 1/4″, 8′ 8 1/4″ and 8′ 9 1/4″. The right wall, listed from the front corner, runs 8′ 9 1/4″, 8′ 6 1/4″, 8′ 2 1/4″, 7′ 10 1/4″, 7′ 6 1/4″, 7′ 2 1/4″, 6′ 10 1/4″, 6′ 6 1/4″ and 6′ 5 3/8″.

The two walls do not mirror each other because the 16 in layout starts from one corner on both. Mark each stud with its wall and position as you cut it. Cut the top of each stud at the roof angle (3 on a speed square, about 14 degrees) and check the first one against the plate before cutting the rest.

Headers. The 60 in door gets a doubled 2×8 header with a 1/2 in plywood filler on 6′ 4 1/2″ trimmers. The front wall is tall, so the four cripples above the header are 1′ 8 7/8″, far longer than on a gable shed. The back window header is a doubled 2×6 on 5′ 10″ trimmers, and it fills the space right up to the plates, so there are no cripples above it. Below the window go a 3′ 0″ sill and two 2′ 8 1/2″ cripples.

Plates. The front and back cap plates run the full 12′ 0″. The side walls have a single sloped top plate, 9′ 8 1/2″, that runs between them, and the 4 twist straps tie the lean-to wall corners together.

Gable vs lean-to: what changes

The same 10×12 footprint run as a gable at 6/12 (94 1/2 in walls, ridge along the 12 ft side) keeps the floor and changes almost everything above it. Our 10×12 shed material list covers the gable version in full.

Item Lean-to (3/12) Gable (6/12)
Rafters 10 2×6 at 11′ 9 1/2″ + 2 fly 20 2×4 at 6′ 5″ + 4 fly
Ridge board None 2×6, cut 12′ 8″
Rafter ties and collar ties None (no ridge, no outward thrust) 8 rafter ties + 4 collar ties
Wall studs 8′ 8 5/8″ front, 6′ 3 1/2″ back, stepped sides 7′ 6″ on all four walls
2×4 framing boards (plus 2 seam blocks and 8 braces in both) 50 91
2×6 boards (not treated) 16 2
T1-11 sheets 14: five 4×10, two 4×9, seven 4×8 16, all 4×8
Roof OSB sheets 6 7
Shingle bundles 6 7
Felt 1 roll, laid double 1 roll, single
Fascia 1×8 1×6
Framing nails 21 lb 29 lb
Extra hardware 4 twist straps 2 gable vents, 2 Z-flashing
Floor (skids, joists, decking) 4, 10, 4 sheets 4, 10, 4 sheets

The lean-to saves 41 2x4s and needs no ridge or gable triangles, but it buys 14 more plain 2x6s and a double layer of felt, and 7 of its 14 siding sheets are 4×10 or 4×9 instead of 4×8. A lean-to sends all its roof water off the back edge, so keep that side clear of fences and paths.

Where the waste goes

Buying by stock length means every cut leaves an offcut. Here is where the scraps on a 10×12 lean-to come from:

  • Rafters: 11′ 9 1/2″ from a 12 ft 2×6 leaves only about 2 1/2 in. There is no room for a bad end, so pick straight boards with square, uncracked ends, and buy one spare if your yard’s stock is rough.
  • Back studs: two 6′ 3 1/2″ studs come out of each 14 ft 2×4, leaving about 17 in. The two door trimmers pair up in one more 14 ft board.
  • Front studs: 8′ 8 5/8″ from a 10 ft board leaves about 15 in each. That is too short for the eight 24 in brace stakes, so cut those from the longest scraps of the job, or buy two extra 2×4 x 8 ft for them.
  • Side studs: the short ones come from 8 ft boards and the tall ones from 10 ft boards, so the offcuts vary from a few inches to over a foot.
  • Floor joists: 9′ 9″ from a 10 ft board leaves 3 in for squaring the ends.
  • Fascia: each 12′ 8″ eave fascia leaves about 16 in of a 14 ft 1×8; each rake fascia leaves about 2 ft.
  • No spares: the counts are exact. Add a few 2×4 x 8 ft if you expect to reject warped or split boards.

No board on this list is longer than 14 ft. A 14 ft board still hangs well past a pickup bed, so flag the overhang or ask the yard to deliver.

Common mistakes

  • Buying 4×8 siding for the front wall. The front wall alone is 109 1/8 in tall, over 8 ft, so the front and part of each side take 4×10 or 4×9 T1-11 sheets. Check that your yard stocks them before you order.
  • Measuring side studs off the wrong end. The left and right walls step the opposite way and do not mirror. Lay out both sloped plates first, then cut and number the studs wall by wall.
  • Single felt at 3/12. The generator doubles the felt from 2/12 up to 4/12. Read the minimum slope on the shingle wrapper, and check your local permit office for the underlayment rule in your area.
  • One birdsmouth instead of two. Each rafter bears on both walls, so it needs a seat at the front and at the back. Mark both from the pattern rafter.
  • Skipping the twist straps. With no ridge, the corners where the sloped side plates meet the front and back walls rely on the 4 straps and the nailing to stay together.
  • Untreated wood near the ground. Skids, rims and joists are pressure treated; plain framing lumber there rots. The USDA Wood Handbook explains why wet, untreated wood decays. Use hot-dip galvanized nails and treated-lumber rated screws in treated wood.

Setbacks, tie-downs and whether a 120 sq ft shed needs a permit vary by town, so check your local permit office before you order. For how to read any list like this one, see our shed material list guide, and for the base under the skids, shed foundation options. For other sizes, try the shed material calculator.

Get the full plan

We do not sell a 10×12 lean-to plan yet. If you want a printed set with every step, the 10×12 gable shed plan and the 10×12 hip roof shed plan are 3DSHEDPLANS PDFs for the same footprint, each with 3D drawings, cut details and its own printable material list.

For a single-slope roof, the 12×14 lean-to shed plan is the nearest size up, and the 8×16 lean-to shed plan is a longer, narrower option. Download the free 12×14 lean-to preview PDF to see the format, or compare every size on the lean-to shed plans and shed plans pages.

Frequently asked questions

How much lumber do I need for a 10×12 lean-to shed?

For a 10×12 lean-to on skids with an 80 in back wall and a 3/12 roof, our generator lists 50 2×4 framing boards, 16 plain 2×6 boards (12 of them 12 ft rafter stock), 12 pressure-treated 2x6s, 4 pressure-treated 4×4 skids and one 2×8 for the door header.

What size rafters does a 10×12 lean-to shed need?

The generator picks 2×6 rafters at 16 in on center, cut from 12 ft boards to 11' 9 1/2". They span 113 in against a 143 in limit at 30 psf ground snow. If you get more snow than that, check your local permit office.

How many sheets of plywood, OSB and T1-11 for a 10×12 lean-to shed?

4 sheets of 3/4 in tongue and groove plywood for the floor, 6 sheets of 7/16 in OSB for the roof, 14 sheets of 5/8 in T1-11 (five 4×10, two 4×9, seven 4×8) and 1 sheet of 1/2 in plywood for the soffit and header fillers.

How many bundles of shingles does a 10×12 lean-to roof take?

6 bundles of 3-tab shingles, including the starter course, for a 3/12 roof of about 148 sq ft with 8 in eaves and 4 in rakes. At 3/12 the felt goes on in a double layer, and one 400 sq ft roll covers it.

Is there a 10×12 lean-to shed material list PDF?

We do not sell a 10×12 lean-to plan yet, so this page is the list. The 3DSHEDPLANS 10×12 gable plan PDF has its own printable material list, and our lean-to plans in other sizes each include one too.

Shed building guides