How much render do I need per square metre?

For one-coat render at 15mm thickness, you need approximately 10kg per m² (about 2.5m² per 25kg bag). Silicone render systems use less - around 7kg/m² for basecoat and 3kg/m² for topcoat.

Do I need mesh when rendering?

Mesh is essential when rendering over external insulation boards or mixed substrates to prevent cracking. For brick and block walls, mesh is optional but recommended at stress points like window corners and where different materials meet.

What is the difference between one-coat and silicone render?

One-coat render is applied in a single 15mm layer and requires painting. Silicone render is a two-coat system with a coloured topcoat that is through-coloured, low maintenance, and self-cleaning. Silicone render costs more but lasts longer without repainting.

What mix ratio for traditional sand and cement render?

For external render, use 1:1:6 (cement:lime:sand) or 1:5 (cement:sand with plasticiser). The scratch coat should be stronger than the top coat. Always use building sand (soft sand), not sharp sand.

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