The unique climate in Quebec affects the joints in masonry walls in Montreal. With the bad weather and the multiple freeze-thaw cycles, the mortar joints found between the masonry units erode and become porous over time.
To prevent water from seeping into your building and the formation of frost boils on your walls, it’s important for the mortar joints to be watertight and in good condition.
Repointing, also known as filling or pointing, involves scraping off the damaged mortar, generally to a depth of two-and-a-half times the thickness of the joint.
Then, it’s important to clean the hollowed-out joint well and moisten its surface to limit water loss from the new mortar.
The new joint must be filled in thin, successive layers with a mortar compatible with the existing mortar.
For the finish, once the mortar has slightly hardened on the surface, it’s possible to give the new joints the same finishes and profiles as the existing ones.