Cracked chimney masonry repaired in Stoneybrook East

When joints need to be cut out and repointed

Five conditions, listed in brick industry guidance, call for repointing rather than surface treatment. We check for each of them during the inspection, joint by joint, on every face of the chimney we can reach.

• Mortar eroded back more than about a quarter inch
• Mortar that crumbles when scraped
• Voids in the joints
• Hairline cracks in the mortar
• Cracks between the brick and the mortar

When brick and joint work come together

Chimney masonry repair covers the mixed jobs. A few cracked or broken bricks among worn joints, a crack that runs through both, or a section where units and mortar have both failed.

Jobs that are only joint work, or only brick replacement, have their own services with their own scope. When the damage is mixed, we handle it as one repair with one boundary, so the new joints and new units are laid together and match each other.

Removing vines without damaging the brick

Ivy shoots work their way into gaps in the mortar and bring moisture in with them. Technical Note 46 says to cut vines away from the wall rather than pull them, which can damage the brickwork, and to let the remaining shoots dry out before brushing them off.

Chemicals and acids are not recommended for the job. Once the growth is gone, any joints it opened are repointed as part of the repair area, since those are the openings water will use next. Where roots have pushed deep into the joints, the repair area extends to sound mortar behind them.

Coatings are not a substitute for flashing

Water repellents and coatings, according to Technical Note 46, should not replace, or be considered equivalent to, essential code-required details that resist water penetration, such as flashing and weeps.

On a chimney, that means a coating cannot fix a failed flashing joint at the roofline or a cracked crown. When those are the real problem, we say so and quote them separately rather than selling a coating in their place. A coating over a flashing problem can even hide the leak for a while, which makes the real repair harder to find later.