Drywall Calculator
How many sheets of drywall do you need for that room?
How this is calculated
- Wall area = 2 × (length + width) × height; add length × width if the ceiling is boarded
- Area × (1 + waste % ÷ 100)
- Sheets = ⌈area with waste ÷ 32⌉, since a 4×8 sheet covers 32 sq ft
- Screws ≈ 1.5 per sq ft, joint compound ≈ 0.05 lb per sq ft (taping and finishing)
Common questions
How many sheets of drywall do I need for a 10×10 room?
Walls only, a 10 × 10 room with 8 ft ceilings has 320 sq ft to cover — 10 sheets exactly, so buy 11–12 with a 10% cutting allowance. Add the 100 sq ft ceiling and it is 420 sq ft, or 14 sheets with waste.
How many sq ft is a sheet of drywall?
The standard 4 × 8 sheet covers 32 sq ft. Longer 4 × 10 (40 sq ft) and 4 × 12 (48 sq ft) sheets exist — fewer seams on tall walls or long ceilings, but harder to handle alone. This calculator assumes 4 × 8; scale up if you use bigger sheets.
How much joint compound do I need?
For taping and finishing, plan on about 0.05 lb of compound per sq ft of drywall — roughly 20 lb per 100 sq ft... in practice a 4.5 gallon bucket covers a decent-sized room. Texture coats add 30–50% on top.
Should I use 1/2-inch or 5/8-inch drywall?
½-inch is the standard for walls and flat ceilings. 5/8-inch is code for many garage ceilings (fire separation), attached garages shared with living space, and gives better sound dampening — check local code. Ceilings under trusses sometimes use 5/8 to resist sagging.
How much waste should I add for drywall?
10% covers normal rooms. Add 15% if you are working around many openings, stairwells, or diagonal cuts, and consider that offcuts under ~2 ft are usually unusable. Precut and layout planning beats waste percentage every time.