Drywall Calculator

Estimate drywall sheets, joint compound, screws, and tape for walls and ceilings with wastage built-in.

Project Inputs

Provide wall perimeter, height, openings, and board options to project material needs.

Adds ceiling area to the total square footage.

Use the board size you plan to hang; the calculator rounds boards up to whole sheets.

How to Use This Calculator

Gather your wall perimeter and height, subtract openings, and let the calculator project the material counts for the selected sheet size.

  • Enter the total wall perimeter and room height in feet.
  • Toggle the ceiling option and add ceiling square footage if you are covering the ceiling as well.
  • Deduct large openings (doors, windows) so materials are not double-counted.
  • Adjust the wastage factor to reflect how tightly you plan to hang and finish the boards.
  • Select the drywall sheet size that matches your deliverable (4×8, 4×10, or 4×12).

Methodology

We compute the wall area, optionally add ceiling area, subtract openings, and then inflate the net exposure by the wastage percentage. Total drywall sheets are rounded up to the next whole board, while finishing materials follow trade heuristics: 1.5 gallons of compound and 1 pound of screws per 100 square feet, and one roll of 500 ft tape per 500 square feet.

  • Net area never goes negative; if openings exceed the gross area an error prompts you to revise the inputs.
  • Materializing ceilings and higher wastage percentages conservatively buffers your order for mistakes.
  • Results reflect typical contractor coverage estimates rather than structural design rules.

Full original guide (expanded)

The legacy audit, source list, and changelog remain intact below so every formula and reference is traceable from the prior Drywall page.

Formulas
Area & material formulas
Wall area
\[A_{wall} = ext{Wall Perimeter} \times ext{Room Height}\]
A_{wall} = \text{Wall Perimeter} \times \text{Room Height}
Gross area
\[A_{gross} = A_{wall} + A_{ceiling}\]
A_{gross} = A_{wall} + A_{ceiling}
Net area
\[A_{net} = \max(0, A_{gross} - A_{openings})\]
A_{net} = \max(0, A_{gross} - A_{openings})
Total area with wastage
\[A_{total} = A_{net} \times \left(1 + \frac{\text{Wastage \%}}{100}\right)\]
A_{total} = A_{net} \times (1 + \frac{\text{Wastage \%}}{100})
Drywall sheets
\[N_{sheets} = \left\lceil \frac{A_{total}}{A_{sheet}} \right\rceil\]
N_{sheets} = \lceil \frac{A_{total}}{A_{sheet}} \rceil
Compound, screws, tape heuristics
Compound = 1.5 gal / 100 sq ft, Screws = 1 lb / 100 sq ft, Tape = 1 roll / 500 sq ft
Compound = \frac{A_{total}}{100} \times 1.5
Screws = \frac{A_{total}}{100} \times 1
Tape = \left\lceil \frac{A_{total}}{500} \right\rceil
Citations
Changelog
  • 0.1.0-draft — 2026-01-19: Initial draft (review required).
    • Initial audit spec draft generated from HTML extraction (review required).
    • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
    • Confirm sources are authoritative and relevant to the calculator methodology.
✓ Verified by Ugo Candido Last Updated: 2026-01-19 Version 0.1.0-draft
Version 1.5.0