Drywall Calculator

Calculate drywall sheets, tape, mud, and screws needed for a room. Includes waste factor.

By Konstantin Iakovlev · Updated April 2026 · Source: HomeAdvisor

ft
ft
Sheet Size

Total Wall Area

327 sqft

incl. 10% waste

Sheets Needed

11

Estimated Cost

$224.00

Materials Breakdown

Gross Wall Area384 sqft
Door Deductions87 sqft
Net Wall Area297 sqft
With 10% Waste327 sqft
Drywall Sheets11 sheets
Joint Tape132 ft
Joint Compound (Mud)17.0 gallons
Screws308

Cost Estimate

Drywall Sheets$132.00
Tape$8.00
Joint Compound$60.00
Screws$24.00
Total Materials Cost$224.00

Use the Drywall Calculator above to calculate your results. Enter your values and see instant results — all calculations run in your browser.

Disclaimer: This calculator is for informational purposes only and does not constitute tax, financial, or legal advice. Results are estimates based on the information you provide and current rates. Always consult a qualified tax professional or financial advisor for advice specific to your situation.

How It Works

Pinning down how many drywall sheets, how much joint compound, and how many fasteners a job needs is what separates a smooth build from one stalled by repeat trips to the supplier. With 2026 installed drywall running an average of $1.50-$3.00 per square foot, a tight estimate keeps both overspending and schedule slips in check.

Start by totaling wall and ceiling area, then take out the openings for doors and windows. Dividing the remainder by the coverage of a standard sheet (32 sq ft for a 4x8) gives the sheet count, which is then padded by a waste factor in the usual 10-15% range. From there, screws, tape, and compound follow from established industry ratios tied to that area.

Round sheet counts up rather than down, because trimming partial sheets only generates scrap, and pad the order further when the layout throws in lots of corners or angles. Factor in changes in ceiling height as well, and bear in mind that a textured finish can call for 20-30% more joint compound than a smooth one.

Living Room Renovation: 320 sq ft Space with $1,280 Material Budget

  1. 1 Calculate total surface area: 12ft × 14ft room with 9ft ceilings = 468 sq ft walls + 168 sq ft ceiling = 636 total sq ft
  2. 2 Subtract openings: 636 sq ft - 80 sq ft (2 windows) - 21 sq ft (1 door) = 535 sq ft net drywall area
  3. 3 Add waste factor: 535 sq ft × 1.10 (10% waste) = 589 sq ft ÷ 32 sq ft per sheet = 18.4 sheets, rounded to 19 sheets
  4. 4 Final materials needed: 19 drywall sheets ($456), 4 lbs joint compound ($32), 2 rolls tape ($16), 5 lbs screws ($25) = $529 total materials, well under the $1,280 budget

Source: HomeAdvisor · Last updated: April 2026

Frequently Asked Questions

How many sheets of drywall do I need for a room?
Calculate wall and ceiling area in square feet, then divide by 32 (for 4x8 sheets) or 48 (for 4x12 sheets). Add 10-15% for waste and cuts. A 12x12 room with 8-foot ceilings needs about 18-20 sheets for walls and ceiling.
How much does it cost to drywall a room in 2026?
Professional drywall installation costs $2.00-$3.50 per square foot including materials, taping, and finishing in 2026. A 12x12 room costs roughly $1,500-$3,000 for walls and ceiling with Level 4 finish.
What thickness of drywall should I use?
Use 1/2-inch for most walls and ceilings with standard 16-inch on-center framing. Use 5/8-inch for fire-rated walls, ceilings below living spaces, and to reduce sagging on 24-inch on-center framing. Use 1/4-inch for curved surfaces.

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