Drywall Calculator

Calculate drywall materials for your project.

Drywall Calculator

Calculate drywall sheets and materials for your project

Room Dimensions

Drywall Installation Tips

  • • Standard door opening is ~20 sq ft, window is ~12 sq ft
  • • Add 5-15% waste for cuts and mistakes
  • • Use 1¼" screws for ½" drywall on wood studs
  • • Space screws 12" on center for walls, 8" for ceilings
  • • Always measure twice and cut once

How to Use the Drywall Calculator

  1. Enter room dimensions: Input length, width, and height for each room in feet.
  2. Select sheet size: Choose from standard sizes like 4'x8', 4'x10', or 4'x12'.
  3. Count openings: Enter the number of doors and windows to subtract from wall area.
  4. Add waste percentage: Include 5-15% extra for cuts, mistakes, and future repairs.
  5. Review results: Get sheets needed, joint compound, screws, tape, and total costs.

Calculation Examples

Standard Drywall Sheet Sizes

Sheet SizeCoverageTypical CostBest For
4' x 8'32 sq ft$12-15Standard walls, easy handling
4' x 10'40 sq ft$15-20Tall walls, fewer joints
4' x 12'48 sq ft$18-25High ceilings, minimal seams

By Thickness

  • 1/4" (6mm): Curved walls, repairs, overlays
  • 3/8" (9.5mm): Existing walls, mobile homes
  • 1/2" (12.7mm): Most common for walls and ceilings
  • 5/8" (15.9mm): Fire-rated, soundproofing, commercial

Special Purpose Types

  • Regular: Standard interior walls and ceilings
  • Moisture-resistant: Bathrooms, kitchens, basements
  • Fire-resistant: Garages, furnace rooms, commercial
  • Soundproof: Media rooms, bedrooms, offices

Frequently Asked Questions

How do I calculate drywall for ceilings?

Measure length x width of ceiling area. Add this to your total square footage. Ceilings typically use 1/2" or 5/8" drywall.

How much joint compound do I need?

Generally, plan for 1 gallon of compound per 100 square feet of drywall for all three coats of finishing.

What size drywall screws should I use?

Use 1-1/4" screws for 1/2" drywall, 1-5/8" screws for 5/8" drywall. For metal studs, use self-drilling screws.

How long does drywall installation take?

Hanging typically takes 1-2 days, but finishing (taping, mudding, sanding) takes 3-5 days with drying time between coats.

Drywall Installation Best Practices

Hanging Drywall

  • Install ceilings before walls
  • Use proper screw spacing (12" walls, 8" ceilings)
  • Stagger joints between rows
  • Keep screws slightly below surface
  • Cut openings after hanging when possible

Finishing Process

  • Apply tape and first coat of compound
  • Sand lightly between coats
  • Apply second coat, feathering edges
  • Final coat should be smooth and wide
  • Prime before painting for best results

Additional Materials & Tools Needed

Materials

  • Drywall screws (1-1/4" for 1/2" drywall)
  • Joint compound (pre-mixed or powder)
  • Paper or fiberglass mesh tape
  • Corner bead for outside corners
  • Primer and paint

Essential Tools

  • Drywall saw or utility knife
  • Screw gun or drill
  • Taping knives (4", 6", 10")
  • Mud pan for compound
  • Sanding blocks or pole sander