How many sheets of drywall do I need for a 12 × 14 ft room, walls and ceiling?
For the worked example (12 × 14 ft room, 8 ft ceilings, ceiling included) the material list is Drywall: 21 × 4 × 8 ft sheets (calculated 20.08 sheets, based on 10% waste, 32 sq ft per sheet); Joint tape: 1 × 250 ft roll (calculated 216 ft, based on 370 ft / 1,000 sq ft); Joint compound: 2 × 4.5 gal pails (calculated 5.3 gal, based on 9 gal / 1,000 sq ft); Drywall screws: Approx. 1.6 lb (calculated 1.58 lb, based on 2.7 lb / 1,000 sq ft (planning default)). Quantities to buy are whole units rounded up from the calculated amounts. Enter your own measurements in the calculator above for your exact list.
How to use this calculator
- Enter the room length, width and height, and keep “Include ceiling” on if the ceiling gets drywall too.
- Pick your sheet size and waste allowance.
- Leave “Subtract doors/windows” off for a safer purchase quantity, or turn it on to subtract them.
- Check the tape, compound and screw rates under Assumptions.
- Copy, print or share the material list.
How this is calculated
- Surface area = 2 × (length + width) × height (+ length × width for the ceiling)
- Board area = surface area × (1 + waste ÷ 100)
- Sheets = round up (board area ÷ sheet area)
- Joint tape (ft) = surface area × 370 ÷ 1,000, then rolls = round up (tape ÷ roll length)
- Joint compound (gal) = surface area × 9 ÷ 1,000, then pails = round up (compound ÷ pail size)
- Screws (lb) = surface area × 2.7 ÷ 1,000
Geometry is deterministic. Material coverage, density, installation waste and product yield can vary. We expose those assumptions so you can replace them with the values printed on the products you are actually buying. Treat every result as an estimate. Items on your list are labelled Calculated (straight from your measurements) or Estimated (depends on an assumption), and “Buy” quantities are whole units rounded up.
Sources
- USG – Sheetrock FAQ on joint compound coverage. Roughly two 4.5 gal pails of Sheetrock UltraLightweight All Purpose Joint Compound finish 1,000 sq ft of gypsum wallboard. Basis for the 9 gal per 1,000 sq ft default. USG product data sheets list roughly 9–10 gal per 1,000 sq ft depending on the compound, so 9 gal is the low end. Other compound types differ.
- USG – Sheetrock Wallboard Estimator. USG’s own estimator notes that its estimate does not include a waste allowance. Why a separate, editable waste allowance is applied to the boards here.
- Ace Hardware listing – USG Sheetrock paper joint tape (retailer page, not a USG specification). About 370 linear feet of paper joint tape per 1,000 sq ft. Taken from a third-party listing of a USG product, not from a USG specification sheet. Confirm against USG literature or the tape you buy. The screw rate is a rough planning default; we found no published USG figure for it.
Last reviewed: . See the methodology.
Assumptions
These starting values are used until you change them. They are typical, not universal. Check the label on the product you are buying.
| Assumption | Starting value | Where it comes from |
|---|---|---|
| Sheet area | 4 × 8 ft = 32 sq ft (and so on) | Mathematical |
| Waste allowance | 10% | Common planning default |
| Joint tape per 1,000 sq ft | 370 ft / 1,000 sq ft | Manufacturer / industry sourced |
| Joint tape roll length | 250 ft | You enter it (product / supplier) |
| Joint compound per 1,000 sq ft | 9 gal / 1,000 sq ft | Manufacturer / industry sourced |
| Joint compound pail size | 4.5 gal | You enter it (product / supplier) |
| Drywall screws per 1,000 sq ft | 2.7 lb / 1,000 sq ft | Common planning default |
Worked example
A 12 × 14 ft room with 8 ft walls and a drywall ceiling, 4 × 8 ft sheets and 10% waste:
- Drywall: 21 × 4 × 8 ft sheets (642.4 sq ft of board) · 10% waste, 32 sq ft per sheet
- Joint tape: 1 × 250 ft roll · 370 ft / 1,000 sq ft
- Joint compound: 2 × 4.5 gal pails · 9 gal / 1,000 sq ft
- Drywall screws: Approx. 1.6 lb · 2.7 lb / 1,000 sq ft (planning default)
Common questions
Why are doors and windows not subtracted by default?
Small openings often do not reduce how many sheets you buy, because cutting around them creates offcuts. You can turn subtraction on if you prefer.
Do the tape, compound and screw numbers apply to every wall?
No. They are planning defaults for a simple case. Different framing, fire-rated assemblies, finishing levels and installation methods can require different amounts. Follow the assembly and product instructions for your project.
Why are screws shown in pounds instead of boxes?
Package sizes vary a lot by brand and store, so we show the weight and leave the package choice to you.
Guides
- How Many Sheets of Drywall Do I Need?Wall and ceiling area divided by sheet size, with waste and rounding.
- How to Measure for Drywall: Walls and CeilingsWalls, ceilings and openings, one room at a time.
- 4×8 vs 4×12 Drywall: How Sheet Size Changes the CountSheet area and sheet count compared for the same room.
- How to Measure a Room for a Material EstimateFloor, wall and ceiling area from a tape measure and a sketch.
- How Much Extra Material Should You Buy?Waste, overage and rounding: what an allowance is and what moves it.