How do you measure amount of cement to buy?

Answer 1

The first step is to measure the volume of the amount of concrete for the job by adding up the volume of concrete required for the various parts of the construction. This is, for each part, Volume = length x breadth x depth.

If a 1 part cement, 2 parts sand, and 4 parts gravel mixture is to be used (a common ratio for foundations), 1 bag of cement (1 cu.ft.) + 2 cu. ft. of sand + 4 cu. ft. of gravel yields 4½ cu. ft. concrete.

So, if the total volume of concrete required is 100 cu. ft. then requirements are:

Cement: 100/4.5 = 23 cu. ft. (probably about 23 bags)

Sand: 2 x 100/4.5 = 45 cu. ft. = 45/27 = say 1 cu yard.

Gravel: 4 x 100/4.5 = 90 cu. ft. = 90/27 = say 3 1/2 cu. yard.