Drywall · basement
How much drywall does a basement need?
In a basement the ceiling is the hard part, not the walls. Ducts, beams and shut-offs all want a box built around them, and every box eats board.
- Walls or walls + ceiling
- Drops and soffits noted
- Copy-ready shopping list
The room
Openings
21 sq ft each
15 sq ft each
Stair openings, archways, a bricked-up fireplace. Measure them — a stairwell hole is 40 to 60 sq ft of wall you do not board.
Sheet size
Thickness
The default for walls on framing at 16 in centres.
Waste is 10%, 2 outside corners. Defaults are fine for most rooms.
Room plan
shape only, not to scale
You need
39sheets
4 × 8 ft · 1/2 in · 10% waste
Materials
$739
at your prices
- Walls
- 704 sq ft
- Ceiling
- 480 sq ft
- Openings
- −51 sq ft
- Net area to board
- 1,133 sq ft
- Sheets before waste
- 36 → 39
- Weight to carry
- 2,221 lb
What to put in the cart
Finishing follows the manufacturer coverage rates: 10 gal of mud and 370 ft of tape per 1,000 sq ft.
- 1$624
39 × 4 × 8 ft 1/2 in drywall sheets
- 2$36
4 × 1 lb box of 1-1/4 in drywall screws (about 1,097 screws)
- 3$14
2 × 250 ft roll of paper joint tape (420 ft needed)
- 4$57
3 × 4.5 gal pail of all-purpose joint compound (11.3 gal needed)
- 5$8
2 × 8 ft corner bead
The whole setup lives in the link — send it to whoever is helping.
Your rooms
A renovation is never one wall. Save each room here and load it when you get to it — kept in this browser only, no account needed.
Nothing saved yet. Set up a wall above, then hit Save this room.
Worked example: A 24 × 20 ft basement room, 8 ft ceiling, walls and ceiling
One door, two windows, two outside corners, 4 × 8 sheets in 1/2 in, 10% waste. The ceiling is fully boarded — the tidy version, with no boxes built around the ducts.
| Walls | 704 sq ft |
| Ceiling | 480 sq ft |
| Openings | −51 sq ft |
| Net area to board | 1,133 sq ft |
| Sheets before waste | 36 |
| Sheets to buy | 39 |
| Screws | 1,097 (about 4 lb) |
| Paper tape | 420 ft (2 × 250 ft) |
| Joint compound | 11.3 gal (3 × 4.5 gal) |
| Weight on the truck | 2,221 lb |
| Heaviest single sheet | 57 lb |
The ceiling is 480 of those 1,133 sq ft. If you are leaving it open and painting the joists, flip the ceiling switch before you buy anything — it is a third of the board.
Turn the ceiling off and it drops to 23 sheets — that toggle is worth 16 sheets, or about 41% of the job.
Where these numbers come from
Three steps. Every coefficient is a published figure, so you can redo any of it on paper.
- 1
Perimeter, then footprint
Walls are 2 × (24 + 20) × 8 = 704 sq ft. The ceiling is 24 × 20 = 480 sq ft. Two different sums, and the ceiling one has nothing to do with the wall height.
- 2
Deduct the holes, then add waste
One door at 21 sq ft and two windows at 15 sq ft each come off the walls. Then 10% goes back on for cuts — basement rooms are usually small and broken up, so 15% is a fair call if yours has a stairwell, a beam or two levels.
- 3
Finish the number, not the job
Screws come from the boarded area at the manufacturer rate, tape at 370 ft per 1,000 sq ft, compound at 10 gal per 1,000 sq ft. Those three are the ones people forget, then drive back for.
Joint compound
10 gal
per 1,000 sq ft of board
Paper tape
370 ft
per 1,000 sq ft of board
Fasteners
16 in / 12 in
walls / ceilings, on centre
What this calculator cannot know
Four things the number has no way of seeing. Better to read them now than at the counter.
- It boards a rectangular room. An L-shaped basement is two rectangles — run each one and add the sheets, because the shared corner wall only gets boarded once.
- Soffits and box-outs around ducts and beams are not counted. They eat board and they eat mud, because every one of them adds four inside corners to tape. If your ceiling plan has boxes, add a sheet or two.
- It does not touch moisture. Below-grade walls need the water problem solved before board goes up — that is a waterproofing and insulation decision, and no calculator can make it for you.
- It assumes a flat ceiling. A dropped ceiling in part of the room, or a bulkhead over a stair, is extra area the room dimensions cannot express.
Questions people actually ask
Including the ones where the honest answer is “ask your inspector”.
How much drywall do I need for a 1,000 sq ft basement?
A 1,000 sq ft basement with 8 ft ceilings is about 1,040 sq ft of wall plus 1,000 sq ft of ceiling — 2,040 sq ft before openings. At 10% waste that is 71 sheets of 4 × 8. Walls only, it drops to 36. The ceiling is not a detail on a basement; it is often more board than the walls.
Should basement ceilings be 5/8 in?
If the joists are at 16 in centres, 1/2 in holds up fine. At 24 in, or if there is anything above that might sag it, 5/8 in is the safer board — it is also the usual choice when the ceiling is a fire separation. Switch the board thickness above and the screw length and weight change with it.
How much does a basement ceiling lower the room?
About 1/2 in of board plus whatever furring or resilient channel you use — call it 1 to 1-1/2 in. That matters in a basement with a 7 ft 6 in clearance, because it is the difference between a legal sleeping room and not. Measure the lowest duct before you commit.
Do I deduct the stair opening?
The stairwell hole in the ceiling, yes — it is area you do not board. The walls around the stair, no, those still get covered. Put the hole in the "other big openings" field and leave the room dimensions to the room.
How much mud and tape for a basement?
Around 10 gallons of ready-mixed compound and 370 ft of paper tape per 1,000 sq ft of board. For the 1,133 sq ft room on this page that works out at roughly 11 gallons — three 4.5 gal pails — and 420 ft of tape, so two 250 ft rolls. Buy the second roll; a splice in the middle of a long seam is not worth saving seven dollars.
Boarding a different room?
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Who wrote this
Shawn Chen
I built these calculators and I keep them up to date. I am not a contractor, so treat this as arithmetic you can check yourself, not as advice from a tradesman.
Last checked and updated
Coverage and fastener figures are the manufacturers' published numbers; the sheet count is the standard area method used across the trade.
Where the numbers come from
- Gypsum Association — GA-216, Application and Finishing of Gypsum Panel Products
- USG — fastener spacing for gypsum board (16 in on walls, 12 in on ceilings)
- USG Sheetrock All Purpose Joint Compound — coverage figures
Coverage and spacing figures are the manufacturers’ own numbers. Where brands disagree, the page uses the lower one.