12 m × 2.6 m wall, 4 m² of openings, 15 mm
Net area 27.2 m²; with 15 % margin, 0.469 m³ of mortar, 164 kg of cement (5 bags of 35 kg) and 657 kg of sand at 350 kg/m³ and 1,400 kg/m³.
Plaster and render calculator
Enter the wall dimensions or the area, the number of faces and the thickness: PRAXAO calculates the mortar to prepare, the cement (in bags) and the sand for your mix, with a margin for waste and uneven walls.
Enter the dimensions to see the drawing.
Calculation results
Fill in the fields to see the result.
Preliminary estimate from the values entered: not a structural validation and not an execution plan. Check the local rules and the manufacturers’ data.
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Results are provided for information. Check tax rates and legal requirements that apply to you.
How to use it
- Enter the wall length and height, or the area directly.
- Deduct doors and windows and choose one or two faces.
- Set the thickness, the waste margin and your mix.
- Read the mortar, the cement bags and the sand to order.
Examples
Frequently asked questions
What thickness for a plaster coat?
A single cement coat is often 10 to 20 mm. Walls that are not plumb need more, and several coats are used above about 20 mm.
Why a waste margin of 15 %?
Rough masonry absorbs mortar and part is lost while working. 10 to 25 % is common; adjust it to your wall.
Does it work for gypsum or ready-mixed plaster?
Those products have their own consumption per m² and per mm, given on the bag. Use the manufacturer’s figure for them.
Guides to go further
BUILNORA
How to calculate plaster and render for a wall
Net area, coat thickness, waste margin, then mortar, cement and sand: the method to order the right quantity of render, with a worked example.
BUILNORA
How to calculate a plasterboard partition
Boarded area, stud spacing, track and screws: the method to count the materials of a metal-stud partition, with a worked example.
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