How much building sand per m2 of wall?

The amount of building sand needed per square meter of wall depends on the type of mortar mix used. Generally, for a standard mortar mix (1 part cement to 3 parts sand), you would need approximately 0.1 to 0.15 cubic meters of sand per square meter of wall. This can vary based on factors like the thickness of the mortar joints and the specific application. Always consult local guidelines or a construction professional for precise calculations.