Walls & ceilings
Drywall Calculator
Estimate drywall sheets, screws, joint tape, compound, waste, coverage, and panel cost for a room.
Estimated order quantity
0 drywall sheets
Planning estimate only. Verify product specifications, site conditions, and supplier purchase increments before ordering.
How the drywall estimate works
Wall area equals room perimeter multiplied by wall height. Doors, windows, and other excluded areas are subtracted, and the ceiling is added only when selected. The result is increased by the visible waste allowance, divided by panel coverage, and rounded up to whole sheets.
Sheets: ceil[net area × (1 + waste) ÷ panel area]
Drywall ceiling calculator
Select Include ceiling to add length × width to the room’s drywall area. Ceiling layouts often create more butt joints and difficult cuts than walls, so review panel direction, joist spacing, lifting requirements and whether a higher waste allowance is appropriate.
Drywall mud, tape and screw estimate
Planning quantities use approximately 0.3 lb of Type W screws, 37 linear feet of joint tape, and 1 gallon of ready-mixed all-purpose joint compound—often called drywall mud—per 100 ft² of installed gypsum panels. These rates follow published USG/CGC planning tables and should be replaced by the selected product and assembly requirements.
Drywall cost calculator
Enter the price of one sheet to estimate panel cost from the rounded purchase quantity. Joint compound, tape, fasteners, corner bead, delivery, tools, tax and labor are shown as planning quantities or exclusions and are not added to the panel-cost total.
Worked example
A 12 × 10 ft room with 8 ft walls, one standard door, two standard windows, and no ceiling has 301 ft² of net wall area. With 10% waste and 4 × 8 ft panels, plan for 11 sheets.
Planning notes
- Measure each room separately when heights or panel orientation differ.
- Fire-rated, moisture-resistant, abuse-resistant, and multi-layer assemblies require project-specific products and quantities.
- Confirm framing spacing, fastener schedule, local code, product instructions, and delivery constraints.
Drywall calculator FAQ
How many drywall sheets do I need for a ceiling?
Select Include ceiling and enter the room length and width. The ceiling area is added before waste and divided by the selected sheet coverage, then the result is rounded up to whole sheets.
How much drywall mud do I need?
The planning estimate uses about 1 gallon of ready-mixed joint compound per 100 ft² of installed panels. Finish level, number of coats, bead, texture, product and crew technique can change actual use.
How many drywall sheets should I add for waste?
Ten percent is a useful starting point for simple rooms. Complex ceilings, short walls, many openings, or diagonal cuts may justify 15% to 20%.
Does the estimate include both sides of a wall?
No. It estimates the four interior room faces entered. Add separate areas or calculate again for partitions requiring drywall on both sides.
Should I use 4 × 8, 4 × 10, or 4 × 12 sheets?
Longer panels can reduce joints but are heavier and harder to transport. Choose a size that matches framing, access, handling, and local availability.