Tool guide
Drywall sheet calculator: how it works
Practical information to understand the result and use this tool correctly.
About Drywall sheet calculator
This drywall calculator estimates plasterboard sheets and the main consumables for a wall run or a simple room. It is a purchase planner, not a site takeoff that already accounts for staggered joints, backing, or cutouts around boxes.
Net area is wall length times height, minus openings, plus an optional ceiling (length times room depth). Each layer multiplies that area. Sheets are the net area times layers and waste, divided by the sheet area, then rounded up.
Screws use a planning density of about 11 per square metre (close to one screw per square foot) and can be edited. Joint compound uses 0.4 kg per square metre of board as a taping-and-finish allowance. Tape is estimated from the long joints implied by the sheet width, not from corner bead.
Limits: openings are subtracted as area, so a door does not reserve a full sheet for patching. Double-layer walls, ceilings, and waste are included only when you enter them. Local sheet names (pladur, drywall, gypsum board) share the same area method.
How to use it
- 1Enter the total wall length, ceiling height, and the area of doors and windows to subtract.
- 2Turn on the ceiling only if you are boarding it, and enter the room depth.
- 3Pick a sheet preset (1.2×2.4 m, 1.2×2.5 m, or 4×8 ft) or type the sheet size, layers, and waste.
- 4Review sheets, screws, compound, and tape. Copy the result before ordering.
Frequently asked questions
- How are drywall sheets calculated?
- Net area is length × height − openings, plus ceiling if enabled. Sheets = ceil(net area × layers × (1 + waste) / sheet area). A 1.2×2.4 m board is 2.88 m².
- How many screws and how much mud should I buy?
- The default is 11 screws per m² of board and 0.4 kg of joint compound per m². Both fields are editable because screw spacing and finish level change the real quantity.
- Does subtracting a door save a full sheet?
- No. Openings reduce area only. Small offcuts around a door often cannot be reused on another wall, so keep the waste percentage if the layout is cut up.
- Is the room size sent anywhere?
- No. The estimate runs in the browser and is not uploaded.
- Why might the job still need more board?
- The tool does not lay out staggered joints, corner bead, soffits, or damaged edges. Order the same batch and an extra sheet if the pattern of cuts is awkward.