Mortar is meant to be the weak point: softer than the brick, so it wears first and can be replaced. On most GTA chimneys the joints near the top wear out after 25 to 40 years, especially on the side that faces the weather. Once they are recessed, water runs into the wall instead of off it.
Repointing means grinding out the failed mortar to a proper depth and packing in new mortar in layers, tooled to match the original joints. On older houses we use a softer mix so the new mortar never ends up harder than the brick, which is what damages heritage brick when it is done wrong.
When to call
- You can scrape mortar out with a key
- Joints sit deeper than the brick face
- Gaps you can see daylight through in the attic
- Water staining down one side of the chimney
- Loose bricks at the top courses
What the visit looks like
- Grind outFailed mortar removed to a consistent depth.
- RepointNew mortar packed in layers and tooled to match.
- Clean and sealMortar haze cleaned off, breathable sealer applied.
