How Many Sheets of Drywall for a Garage?

By Anthony Hudson · Updated July 30, 2026 · 5 min read

The quick answers, for 9-foot walls and ceiling included: a one-car garage (12×22) takes about 30–35 sheets, a two-car (20×22) about 45–50, and a three-car (30×22) about 60–70 — using 4×8 sheets with standard waste. Here's the math and the two garage-specific wrinkles that change what you buy.

The math

A 20×22 two-car garage with 9-foot walls has roughly 756 sq ft of wall (perimeter 84 ft × 9), minus the garage door opening (~130 sq ft for a 16×8 door) and an entry door, plus a 440 sq ft ceiling — call it 1,050 sq ft of surface. Add 10% waste, divide by 32 sq ft per 4×8 sheet: 36 sheets... for finished walls that already exist. Framing-to-finished (both faces of any new interior wall) adds more. Run your exact garage through our drywall calculator — it handles the openings and the ceiling toggle.

Wrinkle one: fire code

The wall between an attached garage and the house — and usually the ceiling if there's living space above — requires 5/8" Type X fire-rated drywall in most US jurisdictions. Many builders simply sheet the whole garage in 5/8" for simplicity and stiffness. It's heavier (make the lift rental decision accordingly) and a bit pricier, but mixing thicknesses to save $50 usually isn't worth the two-pile logistics. Check your local code; the house-side wall is non-negotiable almost everywhere.

Wrinkle two: garages are moist

Cars drip snowmelt and rain; unconditioned garages swing in humidity. Finish the board — tape, mud, and at minimum a coat of PVA primer — rather than leaving bare paper exposed, and consider moisture-resistant board on the bottom course in wet climates. Our primer calculator covers the bare-drywall rates.

The buying list beyond board

Per 1,000 sq ft: about two 4.5-gallon buckets of joint compound, two 500-ft rolls of tape, a 5-lb box of screws, and corner bead for the outside corners. And 5/8" sheets on a ceiling are a two-person-plus-lift job — the $40 lift rental is the best money in the entire project.