What is the formula for brick mortar?

The standard formula for brick mortar begins with one 94-pound bag of Portland cement, 25 pounds of hydrated Type S lime, which is one-half of a typical 50-pound bag, and 28 shovelfuls of masonry sand. These are mixed with 7 or 8 gallons of clean water.

The cement-making process begins by putting two-thirds to three-fourths of the water into a mechanical paddle-type mixer. Then the cement and lime are added. Next comes the sand. During this step, more water is added, when needed, to obtain the proper consistency.

Finally, all components are mixed together for five minutes. The consistency of the mortar depends upon the amount of water added. More water produces thinner mortar.