What is Masonry Cement?
Masonry cement is a mixture of Portland cement, ground limestone and air entrainment (in the form of soap). This mixture creates a mortar with properties that can actually damage historic brick. Masonry cement is hard and inflexible. Because the bricks on historic homes are softer than modern cement, bricks may be damaged as the wall moves and shifts. It traps moisture (is vapor impermeable) which can cause the face of the brick to explode. It also has a lower bond strength, which results in a poorer bond to the brick.
