Clean bricks before remortaring
Photo 1: Chip out old mortar
Chip away the old mortar with a cold chisel or flat utility chisel. Hold the chisel at a low angle, work it in under the mortar and hit the chisel with short, light hammer blows. Dust out the cavity using a whisk broom and dampen it with water to improve mortar adhesion.
When a brick works loose, you can’t just shove mortar in around it and expect the repair to last. Pull it out and fix it right.
It’ll take you at least 20 minutes to remove a loose brick from a wall and clean off the old mortar from both the wall cavity and brick (Photos 1 and 2). If possible, reuse the old bricks. New brick will never match the texture or aged color of the original.
When resetting bricks, follow these guidelines:
- Select bagged mortar mix, not sand or concrete mix.
- Wear safety glasses. Also wear waterproof gloves; mortar contains alkaline chemicals that can burn you.
- Add latex additive to the water and mix the mortar in a shallow container (like an old dishpan) to the consistency of peanut butter.
- Mix small batches of mortar. Hot, dry weather and direct sunlight can reduce the viable working time of the mortar from 60 minutes to 30.
- Immediately clean mortar smears off brick faces using a soft-bristle brush (a wire brush may leave rust marks). If the mortar dries, you’ll have to use chemicals to remove it.