UK DIY Cost Calculator
Masonry & Render Paint Calculator
Work out exterior masonry paint for your walls. Enter the wall dimensions, subtract doors and windows, and account for the extra paint that textured or previously unpainted render absorbs.
Your project
Estimate
Estimates are for guidance only. Coverage rates, pack sizes and prices vary by brand — always confirm quantities with your supplier before buying.
Textured walls change everything
The single biggest variable in exterior paint is surface texture. Smooth render might give 10 m² per litre, but pebbledash and heavy textured coatings can halve that because the paint has to cover a far larger true surface area than the flat measurement suggests. Choosing the right texture option above is what makes this estimate realistic rather than optimistic.
The first coat on bare masonry
Previously unpainted render and masonry are porous and drink the first coat. A stabilising primer or a thinned mist coat is often recommended, and it counts as an extra layer of product, so factor it in when it applies to your walls.
Frequently asked questions
How much masonry paint for a house?
A typical semi-detached elevation of around 100 m² needs roughly 20–30 litres for two coats on smooth render, and considerably more on pebbledash. Enter your own wall dimensions for a precise figure.
Why does pebbledash need so much more paint?
The rough, three-dimensional surface has far more actual area than its flat measurement, and paint pools in the texture. Halving your expected coverage rate is a realistic starting point for heavily textured walls.
Do I need to paint in one go?
Masonry paint is best applied wall by wall in dry weather, avoiding direct hot sun. Buy all your paint from the same batch at once so the colour is consistent across every elevation.
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