Drywall Calculator
Estimate 4x8 drywall sheets for a room's walls. A 4x8 sheet covers 32 sq ft; the calculator deducts ~8% for openings.
Drywall calculator
How it's calculated: Wall area = 2 × (room length + width) × ceiling height, minus 8% for openings; divide by 32 sq ft per 4x8 sheet and round up.
How to estimate drywall
- Add the ceiling separately if you are hanging it too - it is its own square footage.
- Hang sheets horizontally on walls to minimize seams and make taping easier.
- Plan for joint compound at roughly one 5-gallon bucket per ~12 sheets for taping and finishing.
- Use 5/8-inch Type X where fire code requires it - like garage walls under living space - and moisture-resistant board in baths and laundry rooms.
- Store sheets flat or well supported and keep them dry; banged-up or damp edges make taping miserable.
Frequently asked questions
How many drywall sheets do I need?
Divide total wall area by 32 sq ft per 4x8 sheet, then add ~10% for waste and cuts.
Should I use 4x8 or 4x12 sheets?
Longer sheets mean fewer butt joints to tape, which is why pros prefer 4x12 where it fits through the house. For DIY, 4x8 is far easier to carry and hang - a 4x12 is heavy and awkward even with two people.
How many screws per sheet?
Roughly 30 or so per 4x8 sheet at typical 12-16 inch spacing along each stud. Ceilings generally take tighter spacing than walls - follow your local fastening schedule.
What thickness drywall should I use?
1/2 inch is standard for walls. Ceilings get 5/8 inch or sag-resistant 1/2 inch so they do not pillow between joists, and fire-rated assemblies require 5/8 Type X.
Should drywall touch the floor?
No - hold it about 1/2 inch off the floor. The gap stops the board from wicking moisture off the slab, and baseboard hides it anyway.