Ceiling area and sheet estimate
Ceiling square footage = room length × width. A 14×20 ft basement room needs 280 sq ft of ceiling board — nine sheets of 4×8 at 10% waste, or seven sheets of 4×12.
Use our ceiling drywall calculator when walls are already estimated separately — it defaults to including ceiling area in the total sheet count.
Thickness and fire code
1/2 inch gypsum is typical on residential ceilings with joists 16 or 24 inches on center. 5/8 inch Type X is required on some garage ceilings, multifamily demising assemblies, and commercial ratings — check local code.
Heavier 5/8 board needs more screws and a stronger lift — plan help for ceiling hangs regardless of thickness.
Installation technique
Mark joist lines perpendicular to sheet orientation. Apply adhesive in serpentine beads where allowed, then drive screws into joists — misses are obvious when the board sags between fasteners.
Install perimeter screws first to hold the sheet, then fill the field. Butt joints need backer board or clip systems if they fall between joists — never leave a butt joint floating.
- Rent a panel lift for $30–40/day on large ceilings
- Two-person “deadman” T-brace works for small rooms
- Start on the side farthest from the door for headroom while working
- Cut ceiling sheets 1/4 inch short on walls — walls tuck under