The Tiny

A parametric tiny house frame in OpenSCAD: a floor platform, four stud walls and a gable roof. Set the size and the lumber, and it frames the house on a 16 in grid and prints a cut list of what to buy.

Use it

Open src/house.scad in OpenSCAD. All sizes are in inches.

Parameter	Default	Description
length, width	240, 96	Outside size of the floor and walls. The ridge runs along the length.
wall_height	96	Bottom plate to the top of the top plates.
spacing	16	Distance between joist, stud and rafter centres: 12, 16 or 24, so sheet joints land on framing.
joist, stud, rafter	"2x6", "2x4", "2x6"	Lumber sizes.
stock_feet	[8, 10, 12, 14, 16]	Lumber lengths you can buy, in feet.
pitch	6	Roof rise per 12 in.
overhang	12	Eave overhang, measured level from the wall.
ridge_vent	1	Gap left in the roof sheathing each side of the ridge.
subfloor, roof_sheet	"ply 3/4", "ply 1/2"	Sheet goods.
show_floor, show_subfloor, show_walls, show_roof, show_roof_sheathing	true	Show or hide each layer.

The console prints the cut list. For the defaults:

The Tiny: 240 x 96 in, walls 96 in, 6/12 roof
Top plates at 102.25 in; ridge board (2x8) top at 130.27 in
Birdsmouth: seat 3.5 in, notch 1.75 in deep
Buy 2x4: 58 @ 8', 6 @ 14'
  cut 2x4: 2 x 76.5 in, 4 x 80 in, 4 x 89 in, 46 x 91.5 in, 2 x 96 in, 2 x 156.5 in, 4 x 160 in
Buy 2x6: 66 @ 8', 2 @ 14'
  cut 2x6: 32 x 66.25 in, 2 x 80 in, 16 x 93 in, 16 x 96 in, 2 x 160 in
Buy 2x8: 1 @ 8', 1 @ 14'
  cut 2x8: 1 x 80 in, 1 x 160 in
Buy ply 3/4: 6 sheets
Buy ply 1/2: 12 sheets

just cutlist -D length=192 -D width=90 prints it for another size without opening OpenSCAD. It buys one stick per piece at the shortest length that fits, and one sheet per sheet piece; it doesn’t plan cutting several pieces from one stick.

How it’s framed

• Floor. Rim joists run the length of the house; joists span the width between them, one flush at each end and the rest on the grid. The subfloor runs across the joists in 4’ rows, every other row shifted 4’, so every sheet end lands on a joist.
• Walls. The front and back walls run the full length and the end walls fit between them. Each has a bottom plate, studs flush at both ends and on the grid between, and a double top plate. The end walls’ upper top plates lap over the long walls.
• Roof. Rafter pairs sit on the same grid as the studs, plus one pair flush with each end wall. Each rafter has a plumb cut against the ridge board, a birdsmouth seat on the top plate, and a plumb-cut tail. The seat is the wall’s full depth unless that would notch more than a third of the rafter. The ridge board is the first size deeper than the rafter’s plumb cut. A ceiling joist beside each pair ties the walls together, its ends cut to the roof line. Sheathing rows are staggered like the subfloor.
• Long runs. A rim joist, plate or ridge board longer than the longest stock is spliced, and each joint lands on a joist, stud or rafter. Upper top plate joints sit half a piece away from the joints below them.

Sizes that can’t be built stop with a message, for example a width whose joists are longer than any stock, or a roof too low for the ties to pass under the ridge board.

Checks

just test takes about 2 s on OpenSCAD 2026.10.15. It builds the house at four sizes: the default, a 9’2” wide house on 24 in centres at 8/12, a 30’ house in 2x8 and 2x6 on 12 in centres at 4/12 with no overhang, and a 12’ x 7’ house at 12/12. For each it checks that:

• every piece has its stock’s cross-section and fits the longest stock;
• no two members overlap, rafters, ties and roof sheathing included;
• the subfloor covers the floor exactly, in staggered rows;
• every splice joint lands on a member, and upper plate joints sit at least 24 in from the ones below;
• every rafter sits its full seat on a top plate, and no notch is deeper than a third of the rafter;
• the cut list buys one piece of the right stock for every member.

It also checks that four sizes that can’t be built are refused. just images renders the pictures.

Not covered yet

There are no doors or windows, so no headers. The gable ends aren’t framed or sheathed, and the walls aren’t sheathed. Nothing checks spans or loads: pick the joist and rafter sizes from your local span tables. Planned work is in the issue tracker.

Licence

MIT; see LICENSE.