What sort of sand do i use for rendering a breeze block wall?
For rendering an external wall it is best to use a ‘Washed Sand’ type There are a few different types of washed sand, and what type to use will depend on what part of the country you are in….Different quarries supply different types and grades. Your local builders merchant should be able to give you good advice based on your location, and availability of sands in that area. Do not, under any circumstances, be tempted to use ‘Red Sand’ or ‘Building Sand’ as it is commonly called. Building sand is too soft and fine for rendering (although many use it so) and in time it will take in water…..If the water in the render freezes during winter time, the render will expand and spall,and then fall off. A good quality sand for rendering will be made up of grains of slightly differing sizes….This is what gives it its strength.
