ποΈ Drywall Calculator
Calculate sheets, joint compound, tape, and screws for your drywall project.
Drywall Sheets Needed
How to Use This Calculator
Enter your room length, width, and ceiling height. Count your doors and windows for deductions. Toggle the ceiling option if you need drywall on the ceiling as well. Choose between 4x8 and 4x12 sheets, then add your waste percentage. The result includes sheet count plus joint compound and screw estimates.
Measure room length, width, and ceiling height. The calculator figures wall perimeter automatically.
Count doors and windows. The calculator deducts 20 sq ft per door and 15 sq ft per window from total wall area.
Choose sheet size. 4x8 sheets (32 sq ft) are standard and easier to handle alone. 4x12 sheets (48 sq ft) create fewer seams on tall walls and are worth it if you have a helper.
Set waste to 10%. This covers small cutouts for outlets, switches, and short wall sections where a full sheet is not usable.
Drywall Calculation Formula
A 12x14 ft room with 8-foot ceilings and no ceiling drywall has about 398 square feet of wall area after deducting one door and two windows. At 10% waste and 4x8 sheets, that is 14 sheets. You would also need about 21 gallons of compound in total across three coats, or roughly four 5-gallon buckets.
Example Projects
Tips for Your Project
Hang ceiling drywall first, then walls. The wall sheets hold the ceiling sheets against the joists at the perimeter, which makes taping the ceiling-to-wall joints much easier. Use 1-5/8 inch coarse-thread screws for walls and 1-5/8 inch fine-thread screws for metal studs. Coarse-thread screws hold better in wood and drive faster without stripping.
Budget for three separate coats of joint compound: tape coat, filler coat, and finish coat. Each coat adds drying time, typically 24 hours in a climate-controlled space. In a cold or humid basement, drying can take 48 hours per coat. Buy lightweight all-purpose compound for the finish coat since it sands much more easily than regular compound and gives a smoother final surface.
Frequently Asked Questions
How many drywall sheets do I need?
Calculate total wall area (minus large openings), divide by sheet area (4Γ8=32 sq ft or 4Γ12=48 sq ft), add 10% waste.
What size drywall sheets should I use?
4Γ8 ft is standard for walls. 4Γ12 ft reduces joints and finishing work for longer walls. 4Γ16 ft for very long spans.
How much joint compound per sheet?
Approximately 0.053 gallons of all-purpose compound per sq ft of drywall. A 5-gallon bucket covers about 85β100 sq ft.
How many drywall screws per sheet?
Standard: 1 screw every 12 inches on studs in the field, 8 inches on edges. Approximately 30β35 screws per 4Γ8 sheet on 16" stud spacing.
What is the difference between drywall types?
Standard: most walls and ceilings. Moisture-resistant (green/purple): bathrooms. Fire-resistant (Type X): garages, near fireplaces. Soundproof: home theaters.