If specifications call for a 1:2 cement-sand floor topping, would you suggest using a mix containing coarse aggregate?
A 1:2 cement-sand mix is an outdated topping, expensive in cement but easily placed and generally prone to dust if not expertly finished and cured. Floor topping should contain coarse aggregates of a size not exceeding one-third of the floor topping thickness. You can get a better topping using a 1:1:2 mix than the 1:2 cement-sand mix specified. The 1:2 mix will require about 3 sacks of cement per 100 square feet of 1-inch topping, as compared to 2.3 sacks for the 1:1:2 mix. Shrinkage upon drying will be greatly reduced and resistance to abrasion improved by using coarse aggregate.