Home / Drywall calculator
Drywall Calculator
The sheets are the easy part, and they are also the smaller part of the cost. Tell us the room and the framing and you'll get the whole finishing list (mud, tape, screws, bead), with the thickness the code requires for the spacing you have.
- Sheets and square footage
- Mud, tape, screws, and bead
- The thickness the code wants
Project measurements
What are you boarding? This decides the thickness
The usual job is four walls and a ceiling, but the ceiling may need a different type of sheet.
Measurements Tape measure or decimals
Framing and board The spacing is what the code checks
Finish going on
Sheet size
Finish level and allowance Level 5 adds a skim coat over everything
Allowance
How this number is built
With drywall, the code sets the thickness, not the installer. The rest is arithmetic.
The ceiling's framing spacing decides the board
IRC Table R702.3.5 permits 1/2 inch on a ceiling framed at 16 inches on center, and requires 5/8 at 24 inches. The reason is sag: a half-inch sheet spanning two feet carries more of its own weight than the paper and gypsum can hold, and the ceiling bows between the joists before the job is even finished. This is why this page asks for the spacing instead of assuming one.
Not all 1/2 inch board is the same
Ordinary half-inch wallboard and half-inch sag-resistant ceiling board are different products with different edge stamps, and the difference is what an inspector looks for. If a finish is going on that adds water (sprayed or rolled texture, or plaster), the code lets you use 5/8 at 24 inches, or half-inch sag-resistant board, and plain half-inch ceiling board is not that.
The wall between a garage and the house is a fire barrier
IRC R302.6 requires 5/8 inch Type X on the wall or ceiling between a garage and the house, fastened 6 inches on center with all joints taped. Thicker ordinary board does not satisfy it: Type X has a different core, and the rating comes from the assembly. This matters for safety and is easy to miss on a renovation, so use the specified board even if you have another on hand.
Mud is the biggest thing you buy after the board
Mud is where the level of finish shows up. A Level 4 finish runs about 9–10 gallons per 1,000 sq ft of board; a Level 5 full skim adds roughly 16 gallons more to the same area. Compound is sold in 4.5-gallon pails, so that difference is three or four extra pails on a normal house.
About 32 screws on a wall sheet, 40 on a ceiling
The usual rule is 1 screw per square foot on walls at 16 inches on center and 1.25 on ceilings, per ASTM C840. A 4 × 8 sheet is 32 sq ft, which is where the 32 and the 40 come from; a pound of 1¼ inch coarse-thread screws is roughly 240 of them. Drive them until the head is just below the surface, because an overdriven screw breaks the paper face and the paper is what holds. Tape runs 350–500 linear feet per 1,000 sq ft of board.
The board is only 20–30% of the cost
Hanging is $0.25–0.90 per square foot; taping and finishing is $0.75–1.50. On a finished job the board itself is only 20–30% of the cost. So most of a drywall quote is labor, and the level of finish you choose has a real effect on the price. Ceilings run another 15–25% on top, because the work is overhead.
What 1,000 sq ft of board takes
| Material | Quantity | Basis |
|---|---|---|
| 4 × 8 sheets | 32 sheets | or 25 × 4×10, 21 × 4×12 |
| Joint tape | 350–500 linear ft | manufacturer tables; a 500 ft roll |
| Joint compound, Level 4 | 9–10 gal (123–140 lb) | ≈ 280 sq ft per gallon per coat |
| Joint compound, Level 5 | + 16 gal | the full skim coat on top |
| Screws | 768–1,250 | 1.0 per sq ft on walls, 1.25 on ceilings |
| Corner bead | 8 ft lengths | one per outside corner, per story height |
Manufacturer estimating tables (National Gypsum's finishing guide and USG's estimator documentation) rather than a trade standard. They do not agree exactly: National Gypsum puts screws at 768 per 1,000 sq ft and the ASTM C840-derived figure runs to 1,250, so this page shows the range and computes from the spacing you enter rather than picking one. The compound figures assume the joints are filled and finished to the stated level, which is where the real consumption is decided: a heavy first coat uses more compound than the table predicts.
Tiling a bathroom? Drywall is the wrong wall material inside a shower. That needs backer board and a membrane, which the tile calculator covers.
Where these numbers come from
- IRC Table R702.3.5 (2021, unchanged from 2018) for the ceiling requirement by framing spacing, the water-based-texture footnote, and the fastener spacing, plus IRC R302.6 for the garage separation, Type X, and the 6-inch fastening. Read via state code summaries and published tables rather than the code book itself.
- National Gypsum and ProForm's drywall finishing construction guide and ProForm paper tape data sheet (350 ft of tape, 123 to 140 lb of compound, 32 sheets per 1,000 sq ft), cross-checked against USG's Sheetrock estimator documentation (about 10 gal per 1,000 sq ft, about 280 sq ft per gallon per coat, and the Level 5 addition) and Georgia-Pacific's more conservative tape table. ASTM C840 for the screw counts per square foot.
- Some sources claim 5,000 linear feet of tape per 1,000 sq ft. That is roughly ten times every manufacturer table we could find and could not be confirmed, so it is not used.
- 2026 drywall cost guides for sheet prices, installed rates by level, and the hang-versus-finish labor split. Secondary sources only: no gypsum price series could be confirmed cleanly enough to cite, so read these as retail listings rather than trade figures.
The other nine calculators
Every material, same layout, its own crew.
