Drywall Sheet Calculator

How to Measure Drywall Quantity

To estimate drywall for a room, measure each wall's height and width, multiply to get wall area, add all walls together, then add the ceiling area. Subtract approximate area for doors (21 sq ft each) and windows (8–12 sq ft each) if you want a precise number — but many contractors don't bother subtracting small openings since the offcuts are used elsewhere.

Standard residential drywall is 4×8 feet (32 sq ft per sheet). For rooms with 9- or 10-foot ceilings, 4×9 or 4×10 sheets eliminate horizontal seams on the walls, though they're harder to find at local suppliers. 4×12 sheets are common for commercial work or when minimizing butt seams is important.

Drywall Thickness

Most residential walls use ½-inch drywall. Ceilings typically get ⅝-inch for added sag resistance, especially on longer spans. Bathrooms and laundry rooms use moisture-resistant "green board" or fiberglass-mat drywall in wet areas. Fire-rated ⅝-inch Type X is required in garage/living space assemblies and some wall separations per IRC.

Hanging Sequence and Waste

The 10% waste factor in this calculator accounts for cuts around outlets, switches, windows, and the inevitable corner waste. Professional drywall hangers on simple rectangular rooms can achieve 5–8% waste. Complex rooms with cathedral ceilings, multiple windows, arched openings, or built-ins run 12–15%.

UIR's residential remodeling and general contracting crews hang drywall on all types of projects — from basement finishing to full additions. For a written material and labor estimate, contact UIR.