Drywall calculators

Estimating drywall

The drywall calculator works out sheets for walls and ceilings by sheet size, subtracts doors and windows, and builds the rest of the shopping list from the same measurements: joint compound, paper or mesh tape, screws and corner bead. A chart of standard sheet sizes, thicknesses and weights sits alongside it.

Plan on 10 to 15% extra board. Rooms with many openings, sloped ceilings or short wall sections waste more. Longer sheets (10 or 12 feet) reduce the number of butt joints to finish but are heavier and harder to carry up stairs. For ceilings framed at 24 inches on center, use 5/8 inch board or 1/2 inch board rated sag-resistant.

Mud and tape scale with the length of the joints rather than the area alone, so the calculator estimates them per sheet. Insulation goes in before the board: see the HVAC and insulation calculators for batts and blown-in. Painting comes after, and the painting calculators handle primer and finish coats.

Hanging drywall is manageable for a careful DIYer; taping and finishing to a smooth level 4 or level 5 surface is where professionals earn their money. Fire-rated assemblies, such as the wall and ceiling between a garage and living space, have specific board and fastening requirements, so check local code before you buy.

How each calculator is specified, tested and corrected is described on our methodology page.