Plastering & Rendering

Can you render with sand and cement, but finish surface with k-rend?

Anonymous user 09/03/2024 - 3.11 PM

Hi, I want to render the front of my house which has very hard painted render. This render has not cracked anywhere (after many years), so I'm thinking of leaving it on. But to get good adherence to the paint, I will cover walls with galvanised steel hex mesh netting (chickenwire) and fix securely with masonry screws and washers. Then before starting the rendering I will 'paint' walls with a diluted PVA to add stickiness. Good idea? I'm thinking to render my scratch coat with a sand and cement mix (1:5) with added SBR; two coats with a layer of glass fibre mesh in the middle. And my finishing coat also with sand/cement/lime. However, my main question is: If I wanted the water-resistant maintenance-free benefits of a silicone render, could I just apply a primer and thin layer of silicone render? (eg. Johnstone's Stormshield Silicone enhanced Primer and Render 1.5mm from Selco). In other words, will the sand/cement 'base' be as good as if I used the whole Johnstone's Stormshield system (keycoat, basecoat, mesh, basecoat, silicone primer and silicone render....which will be much more expensive!)?