Drywall Calculator

A drywall takeoff starts with the wall surface that must be covered. For a rectangular room, wall area equals twice the sum of length and width multiplied by ceiling height. This calculator subtracts twenty-one square feet for each standard door and twelve square feet for each standard window. It then estimates sheets and finishing supplies from the resulting net area. Measure unusual openings separately and adjust the counts or your final order when their dimensions differ substantially from these assumptions. Drywall panels are commonly four feet wide and eight, ten, or twelve feet long. Larger panels can reduce seams but are heavier and may be difficult to move through a building. The calculator divides net wall area by the selected sheet area, adds a fifteen percent cutting and waste allowance, and rounds up to a whole sheet. Layout matters: a room may need additional panels because narrow strips and offcuts cannot always be reused even when total square footage appears sufficient. Finishing quantities use practical planning rates. Joint compound is estimated at two and one-half gallons per one hundred square feet, allowing for multiple coats over joints and fasteners. Screws and tape are each estimated at one purchasable unit per one hundred square feet, then rounded upward. Actual compound use varies with finish level, installer technique, corner count, bead details, panel condition, and whether compound is premixed or setting type. Screw requirements also depend on framing spacing and applicable fastening schedules. The cost result multiplies rounded purchase quantities by the prices entered. This mirrors shopping more closely than costing fractional containers. It does not include corner bead, adhesive, primer, paint, delivery, tax, tools, lifts, disposal, or labor. Moisture-resistant, fire-rated, abuse-resistant, or specialty acoustic panels often cost more than standard board and may require different accessories. Confirm product compatibility and local code requirements before ordering. For reliable planning, measure every wall, note ceiling heights, count actual openings, and sketch panel orientation. Calculate separate rooms when dimensions or panel types differ, then combine purchase quantities while preserving a reasonable spare allowance. Compare the estimate with a panel layout and supplier stock lengths. The calculator is most useful as a fast baseline: it translates room geometry into a consistent materials list, helps compare panel sizes, and gives DIY users and contractors an early budget before a detailed takeoff.