Material estimator

Drywall Calculator

Estimate drywall sheets, wall and ceiling area, waste-adjusted square footage, and sheet cost for a room.

How This Calculator Works

Drywall is bought in sheets, so the useful estimate is whole sheets after wall area, optional ceiling area, and waste are included.

Wall area = room perimeter x wall height. Add ceiling area if needed, apply waste, then divide by sheet coverage.

The default sheet coverage is 32 sq ft for a 4 ft by 8 ft sheet. Change coverage to 40 for 4x10 or 48 for 4x12 sheets.

A 12 ft by 12 ft room with 8 ft walls, ceiling included, 10% waste, and 4x8 sheets needs about 19 sheets.
A 10 ft by 12 ft room with 8 ft walls, ceiling included, 10% waste, and 4x8 sheets needs about 17 sheets.
A 20 ft by 15 ft room with 9 ft walls, ceiling excluded, 10% waste, and 4x12 sheets needs about 29 sheets.
A 12 ft by 8 ft wall-only repair with 10% waste and 4x8 sheets needs about 4 sheets.

Change sheet coverage to match the board size you plan to buy: 32 sq ft for 4x8, 40 for 4x10, and 48 for 4x12.
Larger sheets reduce seams but are harder to move, lift, and fit through tight spaces.
Estimate joint compound, tape, screws, corner bead, and delivery separately from sheet count.

Use 10% waste for simple rooms and more for closets, stairwells, many openings, or awkward cuts.
For rough planning, leaving normal door and window openings in the area often covers offcuts and breakage.

Do not forget ceilings when the room is being fully hung.
Do not choose sheet length from price alone; seams, handling, and delivery can matter more than a small material difference.

A 4 ft by 8 ft sheet covers 32 sq ft before cuts and waste.

For rough planning, many people leave openings in the area and let waste cover cuts. For large openings, subtract them manually.

No. This page estimates sheets and sheet cost only.