Quick answer
A 16 × 12 ft room with 8 ft ceilings, ceiling included and 40 sq ft of openings needs about 17 sheets of 4×8.
How it works
Add up wall and ceiling area, subtract doors and windows, then divide by the sheet size and add 10% for waste.
Formula
Sheets = (walls + ceiling − openings) × 1.1 ÷ sheet area
Assumptions & limitations
- Standard waste factor of 10%; complex rooms with many corners may need more.
Frequently asked questions
4×8 or 4×12 sheets?
4×12 sheets mean fewer seams on long walls but are heavier and harder to handle.