Family-owned chimney masonry repair in Dover Shores East

Signs that point past routine masonry repair

Brick Industry Association Technical Note 46 lists conditions that are structural rather than routine maintenance, and says they generally warrant investigation by a professional engineer.

When we see any of them, we tell you before quoting a repair, because patching a crack that is caused by movement tends to crack again.

• Cracks wider than about 0.075 inch, or 2 mm
• Cracks that pass through several bricks
• Cracks that follow a stepped or diagonal pattern
• Widespread spalled brick
• Masonry that has moved out of plane

Tinting mortar to match

Matching an existing joint color sometimes needs pigment. Brick industry guidance calls for metallic oxide pigments rather than organic chemicals, and limits how much can be added so the mortar keeps its properties.

Several sample batches may be needed to get close. We do that work before the repair begins, so the color decision is made with you looking at the samples against your own chimney rather than at a chart. Pigment is added by weight and measured, not by eye, so the same color can be mixed again for each batch on the job.

Cleaning brick without damaging it

Cleaning can harm brick when it is done badly. Brick industry guidance warns that too little prewetting, too little rinsing or strong chemical concentrations can cause new staining, etch mortar joints and increase moisture penetration.

When cleaning is part of a masonry repair, we use products made for brickwork, follow their instructions and test a small area first. A harsh cleaner can do more visible harm in an afternoon than years of weather.

Rust on steel supports in the masonry

Accumulated rust on steel lintels or shelf angles is one of the conditions brick industry guidance lists as possibly structural. Rusting steel expands and can crack the masonry around it.

Where a chimney has steel supporting masonry, such as over an opening or at a change in width, we check it for rust and cracking. When the steel itself is failing, we say so plainly and explain whether an engineer's evaluation should come before the masonry repair. Replacing or treating that steel is a separate decision from the masonry around it, and the estimate keeps the two apart.