About this calculator
Paint for the outside of a house, including triangular gable ends, with an allowance for rough surfaces that soak up more paint.
How it’s calculated
Area = perimeter × eaves height + ½ × gable width × gable height for each gable − openings. Texture multiplies the area. Paint = area × coats ÷ coverage. Plascon gives a theoretical spread rate of 12 m² per litre for Wall & All, in 1, 5 and 20 litre tins; rough and bagged walls take more.
Worked example
With these inputs:
- House perimeter
- 40 m
- Wall height (eaves)
- 5 m
- Gable ends
- 2
- Gable width
- 8 m
- Gable height (eaves to peak)
- 2.5 m
- Doors and windows area
- 12 m²
- Surface
- Smooth plaster or fibre-cement
- Coats
- 2
- Coverage (m² per litre)
- 12
the result is:
- Paint needed
- 34.7 L
- Wall area (net)
- 208 m²
- Texture-adjusted area
- 208 m²
Tips from the trade
- Soffits and fascias are extra. Add them as their own line in your job.
- Spraying uses 20–30% more than rolling because of overspray.
Results are estimates for planning and pricing. Check quantities against your drawings, the manufacturer’s data and SANS 10400 (the National Building Regulations) and your local municipality before ordering.