Non-bearing partition · unfinished basement
Set the real dimensions and end conditions on the left. The elevation, the section details, the cut list and the build order all redraw as you type.
| Member | Size | Cut length | Qty | Buy |
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| Buy | Qty | What it is for |
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This is a stud wall calculator for the most common basement job: a straight, non-load-bearing partition framed in place between a concrete slab and the floor joists above. You enter the real height and length of the wall, choose 16 or 24 in. on-center stud spacing, 2×4 or 2×6 lumber, a single or double top plate, which way the joists above run, what each end of the wall lands on, and an optional door rough opening. From that it draws the framing elevation, works out the stud count and the tape marks for the layout, writes the cut list, packs the pieces onto the fewest boards you can fit in your vehicle, and writes a build order you can follow on the day.
Nothing is stored and nothing is sent anywhere — the numbers are worked out in your browser as you type. Use it to plan a laundry room wall, close off a furnace room, build a basement bedroom partition, or frame a storage closet.
These are ordinary residential conventions, not a code citation. Basements have their own rules for egress, insulation and moisture, and some jurisdictions want a permit for any new wall — check with your local building department before you buy lumber.
At 16 in. on center a 12 ft (144 in.) non-bearing wall takes 10 studs: one at each end plus 8 on layout. At 24 in. on center it takes 7. Add 2 king studs and 2 jack studs for every door opening. Enter your own length above and the calculator counts them for you, including the extra studs a doorway adds and the ones it removes.
Either works for a non-load-bearing partition. 16 in. on center is the usual choice: drywall edges land on a stud every 48 in., the wall feels stiffer, and it costs only a few extra studs. 24 in. on center uses less lumber and is fine for a closet or utility partition, but ½ in. drywall spans more loosely and thinner panelling can oil-can between studs.
Only where wood touches concrete: the bottom plate and any end stud fastened flat to a concrete wall. Every stud and the top plate stay ordinary kiln-dried framing lumber. Put a foam sill gasket under the bottom plate so the pressure-treated wood is not sitting directly in slab moisture.
Snap a chalk line, lay a foam sill gasket, then fasten the pressure-treated bottom plate with 3/16 × 3¼ in. concrete screws (Tapcon style) every 24 in. and within 8 in. of each end. You need a hammer drill and the matching 5/32 in. carbide bit. Powder-actuated nails also work but are harder to remove if you need to shift the plate.
A prehung 32 in. door normally needs a rough opening 34 in. wide by 82½ in. tall — the door width plus 2 in., and the height plus about 2½ in. A 30 in. door needs 32 × 82½ in., a 36 in. door 38 × 82½ in. Check the sheet that comes with your specific door; the calculator lets you type any rough-opening size and places the kings, jacks, header and cripples around it.
Nothing above the wall is carried by it, so a structural header is not required. A single 2× laid flat across the jacks is enough to carry the cripples and give the door casing something to nail to. If the opening is tall enough that the flat header lands within 1½ in. of the top plate, skip the cripples and use a taller header tight to the plate.
A single top plate is fine on a non-bearing partition that no other wall ties into, and in a low basement it gives back 1½ in. of headroom. Use a double top plate when another wall will intersect this one and you want the plates to lap, or if local code asks for it.
Then there is nothing directly above the top plate to screw into. Cut 2× blocks to fit flat between the two joists on either side of the wall line, spaced every 24 in. and flush with the joist bottoms, and screw the top plate up into the blocks. If the joists cross the wall line, the plate screws straight up into each joist and no blocking is needed.
Yes. Switch the Units toggle to Centimeters and every input and every output — stud layout, cut list, shopping list and the build steps — is shown in centimeters. Lumber is still named by its North American nominal size (2×4, 2×6) because that is how it is sold.
No. Everything here follows ordinary practice for a non-load-bearing partition. A wall that ends up under a beam, a post or a bearing point needs a sized header and a designed load path, and that is a job for your local building department or an engineer.