Drywall calculator
How many sheets of drywall you need for a room's walls and ceiling, with the weight, screws, tape, mud and cost: a quick takeoff for a homeowner or a bid.
Your material adds up to
18 sheets of 4 × 8 ft
- Area to cover
- 496 sq ft
- Weight
- 922 lb (51.2 lb a sheet)
- Drywall screws
- 1.3 lb
- Joint tape
- 184 ft (1 × 250 ft roll)
- Joint compound
- 5.0 gal all-purpose
- Primer
- 1.2 gal
- Estimated cost of sheets
384 sq ft of walls minus 32 sq ft of openings, plus 144 sq ft of ceiling. Sheets include your 10% extra. Screws, tape, mud and primer use USG's estimating rates for the area covered; lightweight compound takes about 4.5 gal. Weights are manufacturers' nominal figures.
How many sheets of drywall do I need?
USG's installation guide says to measure the length and height of each wall, multiply to get square feet, subtract large openings such as doorways and picture windows (not outlets or pipes), do the same for the ceiling, and divide the total by the size of the sheet. The calculator does that for a rectangular room, then adds your extra for cut-offs and breakage.
- Walls = 2 × (length + width) × wall height
- Openings = doors × 20 sq ft + windows × 12 sq ft
- Ceiling = length × width, if you're covering it
- Sheets = (walls − openings + ceiling) × (1 + extra %) ÷ sheet size (32 sq ft for 4 × 8 ft, 40 sq ft for 4 × 10 ft, 48 sq ft for 4 × 12 ft), rounded up
- Screws, tape, mud and primer = area ÷ 1,000 × USG's quantity per 1,000 sq ft (table below)
Worked example
A 12 × 12 ft room with 8 ft walls, one door and one window: the walls are 2 × (12 + 12) × 8 = 384 sq ft, less 32 sq ft of openings, plus a 144 sq ft ceiling = 496 sq ft. With 10% extra that's 545.6 sq ft, and 545.6 ÷ 32 rounds up to 18 sheets of 4 × 8 ft, about 922 lb of 1/2 in. regular board. Finishing it takes about 1.3 lb of screws, 184 ft of tape and 5.0 gal of all-purpose compound.
How much a sheet of drywall weighs
Nominal weights from manufacturers' data sheets. Brands and product lines differ, so the range shows both makers where two publish a figure. Lightweight 1/2 in. board weighs less than regular; the label says which you have.
| Thickness | lb per sq ft | 4 × 8 ft sheet | 4 × 10 ft sheet | 4 × 12 ft sheet | Source |
|---|---|---|---|---|---|
| 1/2 in. regular | 1.60 | 51 lb | 64 lb | 77 lb | National Gypsum Gold Bond submittal 110638 |
| 1/2 in. lightweight | 1.25 | 40 lb | 50 lb | 60 lb | USG Sheetrock UltraLight product page |
| 5/8 in. Type X (fire-rated) | 2.20 | 70 lb | 88 lb | 106 lb | USG Sheetrock Firecode X product page |
| 3/8 in. | 1.40 (1.30 to 1.40) | 45 lb | 56 lb | 67 lb | USG submittal WB1473; National Gypsum submittal 110638 |
| 1/4 in. | 1.20 (1.10 to 1.20) | 38 lb | 48 lb | 58 lb | USG submittal WB1473; National Gypsum submittal 110638 |
Materials per 1,000 sq ft of drywall
From the USG Sheetrock Brand Installation and Finishing Guide (J371, rev. 9-15). USG says compound coverage "can vary widely" with the wall, tools and finisher; the figures cover flat joints, inside corners and outside corners with metal bead in a typical room.
| Material | Per 1,000 sq ft | Notes |
|---|---|---|
| 1-1/4 in. Type W screws | 2.7 lb | Spaced 12 in. on ceilings, 16 in. on walls |
| Drywall nails (instead of screws) | 5.3 lb | For 1/4, 3/8 and 1/2 in. panels |
| Paper joint tape | 370 ft | Sold in 250 and 500 ft rolls |
| All-purpose joint compound | 10 gal | Ready-mixed |
| Lightweight all-purpose compound | 9 gal | About two 4.5 gal pails |
| Primer | 2.5 gal | At 400 sq ft per gallon |
Maximum framing spacing
For a single layer on wood framing, from the same USG guide. Fire-rated walls and ceilings follow their tested design, and local codes and the product's instructions come first.
| Thickness | Where | Sheet direction | Max. spacing | Notes |
|---|---|---|---|---|
| 3/8 in. | Ceiling | Perpendicular | 16 in. | Not recommended below unheated spaces or under water-based texture |
| 3/8 in. | Wall | Parallel or perpendicular | 16 in. | |
| 1/2 in. | Ceiling | Parallel | 16 in. | Not recommended under water-based texture |
| 1/2 in. | Ceiling | Perpendicular | 24 in. | 16 in. if water-based texture will be applied |
| 1/2 in. | Wall | Parallel or perpendicular | 24 in. | |
| 1/2 in. UltraLight | Ceiling | Parallel or perpendicular | 24 in. | |
| 5/8 in. | Ceiling | Parallel | 16 in. | Not recommended under water-based texture |
| 5/8 in. | Ceiling | Perpendicular | 24 in. | |
| 5/8 in. | Wall | Parallel or perpendicular | 24 in. |
Drywall questions
How many sheets of drywall for a 12x12 room?
With 8 ft walls, one door and one window, a 12 × 12 room has 496 sq ft of walls and ceiling to cover: 18 sheets of 4 × 8 ft with 10% extra. Press "12 × 12 room" above to start from it, then change the height, openings or sheet size. Longer sheets mean fewer joints to tape: on walls taller than 8 ft or long runs, 4 × 12 sheets save finishing work if you can get them into the room.
How many sheets of drywall for a 1,500 sq ft house?
Floor area alone doesn't tell you, because drywall covers walls and ceilings and every interior wall has two sides. Even a plain 50 × 30 ft box (1,500 sq ft) with 8 ft walls needs 2,780 sq ft for its outside walls and ceiling, or 96 sheets of 4 × 8 ft with 10% extra, before a single interior wall. For a real house, measure room by room with "Room size" (choose "Walls only" for a wall you've already counted from the other side), add the totals, and use "Square feet" for the sum.
How much does a sheet of drywall weigh?
A 4 × 8 ft sheet of 1/2 in. regular drywall weighs about 51 lb (1.60 lb per sq ft, from National Gypsum). Lightweight 1/2 in. board such as USG's UltraLight is about 40 lb, and a 4 × 8 ft sheet of 5/8 in. Type X (fire-rated) is about 70 lb. Longer sheets weigh proportionally more; the table above lists every size, and the calculator totals the weight for your order, which helps with delivery and carrying it upstairs.
How thick is drywall?
Standard drywall comes in four thicknesses: 1/4, 3/8, 1/2 and 5/8 in. Half-inch is the usual single layer for walls and ceilings in homes. Five-eighths Type X is fire-rated board, used where a fire-rated wall or ceiling calls for it; your local code says where that is. USG says 1/4 in. shouldn't be used as a single layer, only over existing walls and ceilings or as an extra layer for sound control, and recommends 3/8 in. for walls and ceilings on framing up to 16 in. apart, for extra layers and for covering old surfaces. The framing table above shows how far apart the studs and joists can be for each thickness.
How much drywall mud, tape and screws do I need?
USG's estimating table gives, per 1,000 sq ft of drywall, about 370 ft of tape, 10 gal of all-purpose joint compound (or 9 gal of lightweight, about two 4.5 gal pails), and 2.7 lb of 1-1/4 in. drywall screws spaced 12 in. apart on ceilings and 16 in. on walls. The calculator scales those to your area. Compound use varies a lot with the finisher and the level of finish, so buy a little more if you're new to taping, and keep the receipt.
How much does drywall cost?
Enter the price of one sheet above and the calculator multiplies it by the sheets you need. Hanging and finishing labor varies widely by region and by the level of finish you want, so get quotes for installation; use this calculator to check the material quantities on them.