Drywall Calculator

Wall area = 2 × (length + width) × height. Add ceiling area = length × width when hanging board overhead. Subtract openings that will not receive drywall. In Metric, use metres for dimensions and m² for area.

A 4×8 sheet covers 32 sq ft, so 500 ÷ 32 = 15.625 → 16 sheets before waste. With 10% waste, 550 ÷ 32 = 17.1875 → plan for 18 sheets. Use Known area mode to confirm with your waste percent.

1,000 ÷ 32 = 31.25 sheets before waste. With 10% waste, 1,100 ÷ 32 = 34.375 → plan for 35 sheets.

With an 8 ft ceiling and walls only: 2 × (10 + 10) × 8 = 320 sq ft → 10 sheets of 4×8 before waste. With ceiling included: 320 + 100 = 420 sq ft → 14 sheets before waste. At 10% waste with ceiling, 462 ÷ 32 = 14.4375 → 15 sheets. Height and openings change the result.

With an 8 ft ceiling included: walls 384 + ceiling 144 = 528 sq ft. With 10% waste and 4×8 panels: 580.8 ÷ 32 = 18.15 → 19 sheets. That is the default worked example in this calculator.

Walls at 8 ft: 2 × (20 + 20) × 8 = 640 sq ft. Ceiling: 400 sq ft. Total 1,040 sq ft. With 10% waste: 1,144 sq ft → about 36 sheets of 4×8 (1,144 ÷ 32 = 35.75 → 36). Adjust height, openings, and panel size for your plan.

Include the ceiling when you will hang drywall overhead. Leave it off for walls-only jobs. Turning Include ceiling on/off immediately changes net area, sheets, screws, tape, and compound in this tool.

Yes—large openings that will not receive drywall can be deducted. Use total opening area or door/window sizes and counts. The calculator rejects openings that exceed the available drywall surface instead of silently clamping to zero.

About 10% is a common planning default for many simple rectangular rooms. Waste covers cuts, damaged sheets, awkward offcuts, corners, and layout variation. Complex shapes or many openings may need more—enter the percent that matches your job.

A 4×8 sheet covers 32 sq ft of face area. That is the most common residential panel size in North America.

A 4×12 sheet covers 48 sq ft. Larger sheets can reduce seams, but they are heavier and harder to handle—availability and ceiling height often decide the choice.

4×12 panels cover more area per sheet and can reduce seams on long walls or ceilings, but they are harder to carry and hang. 4×8 is more common and easier for DIY. Choose based on room dimensions, crew, and local stock—not a universal rule.

This calculator shows approximate screws using about 1 per sq ft on walls and 1.25 per sq ft on ceilings. Real counts depend on framing spacing, panel orientation, wall vs ceiling, wood vs steel, and code or manufacturer fastening schedules—about 1,000 screws per 1,000 sq ft of walls under the wall planning factor alone.

A common planning reference is about 370 linear ft of joint tape per 1,000 sq ft (0.37 ft per sq ft). Actual seam length depends on sheet size, orientation, and room geometry.

It depends on product type and finish level. Planning rates in this tool: conventional all-purpose ready-mix ≈ 10 gal / 1,000 sq ft; lightweight ready-mix ≈ 9 gal; lightweight setting-type ≈ 52 lb; conventional setting-type ≈ 72 lb. Level 5 / skim coats often need more—check the product label.

Estimate required tape length, then divide by roll length and round up. Example: ~195 ft of tape with 250 ft rolls → 1 roll; with 75 ft rolls → ceil(195 ÷ 75) = 3 rolls. Enter roll length in the calculator when you want a roll count.

Select a compound type, estimate gallons or pounds, then divide by pail or bag size and round up. Example: ~5.3 gal of ready-mix in 4.5 gal pails → ceil(5.3 ÷ 4.5) = 2 pails. Optional container size fields drive that estimate.

Use Quantity for identical rooms, or run each room separately and add sheets. For irregular spaces, use Known drywall area with the summed net area.

Measure each wall face (and ceiling if finishing it), subtract large openings, then enter Known area—or use room dimensions when the space is a simple rectangle. Basements often have more corners and bulkheads; consider a higher waste percent.

Switch to Metric: room size in metres, known area in m², custom panels in millimetres. The tool converts the same physical project when you change unit systems.

Enter an optional price per sheet to see estimated drywall sheet cost = sheets × price. That figure does not include screws, tape, compound, labor, tax, or delivery unless you price those separately.

Yes. Horizontal vs vertical hanging changes seam length and often tape and mud demand. This calculator’s sheet count is area-based and does not optimize orientation—plan seams separately for finishing.

It applies exact area formulas with full internal precision and rounds purchasable sheet counts up. Real jobs still vary with layout, offcut reuse, openings, framing, and finish level. Verify panel sizes and product coverage before you buy.

In everyday speech, yes—Sheetrock is a brand name often used for gypsum board. Panels also come in 4×9, 4×10, and 4×12 sizes and in several thicknesses. Use Custom panel size for non-standard faces.