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Plaster calculator
Bags of skim and undercoat, and sheets of plasterboard, for a room or a set area.
You'll need about
- Area to plaster
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- Plasterboard (2400 x 1200)
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- Hardwall (25kg bags)
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- Multi-Finish (25kg bags)
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Includes your wastage allowance. Based on manufacturers' coverage figures; uneven walls and thicker coats will use more.
Get the full job measuredHow the numbers are worked out
| Material | Coverage |
|---|---|
| Thistle Multi-Finish, 25kg | About 10 m² at 2mm |
| Thistle Hardwall, 25kg | About 3 m² at 11mm |
| Plasterboard, 2400 x 1200mm | 2.88 m² per sheet |
Wall area is the room perimeter times the ceiling height, less the openings you enter. The ceiling is length x width. If you enter a total area, the room sizes are ignored.
Things the calculator doesn't cover
- Bonding coat on smooth or low-suction backgrounds such as dense concrete, which covers differently to Hardwall.
- Scrim tape, angle beads, PVA and board adhesive or screws.
- Extra board for double-boarding fire-rated ceilings or partitions.
Need the whole job measured?
Send us your drawings and we take off every item, price it at current UK rates and send back an itemised estimate. From £120, in 3–5 working days.