Drywall Sheets for a 20×20 Room with 9 ft Ceilings
Calculate the number of 4×8 drywall sheets needed for a large 20×20 room with 9-foot ceilings.
How to use this tool
- Enter the room's length, width, and wall height in feet.
- Set the waste allowance (10% is standard; use 15% for complex rooms).
- The calculator outputs total wall area and the number of 4×8 sheets to buy.
A 20×20 open-plan living room with 9-foot ceilings is a common renovation scenario — estimate your drywall here.
Frequently asked questions
- How many drywall sheets do I need?
- Calculate the total wall area (perimeter × height), divide by 32 ft² per 4×8 sheet, and add a 10% waste factor for cuts and mistakes.
- What size are standard drywall sheets?
- The most common size is 4 ft × 8 ft (32 sq ft per sheet). 4×12 sheets are also available and reduce seams on tall walls.