Case Study: 2 Chimney Repairs
Before and After
Stages of Chimney reconstruction
Rebuild the chimney with new bricks,
Replace the broken pre-cast chimney cap pieces with a cement cap,
Add a flue rain-cover,
Caulk the flashing,
Use high-temperature caulking.for the furnace vent.
The Underlying Problems:
The cement was much stronger than the brick - which leads to brick breakage.
The pre-cast chimney cap's seams failed.
Down to solid structure
The chimney bricks are removed, down to below the flashing, then down to a secure base.
Clean, safe site.
A tarp keeps small debris from being buried in the lawn.
Drop-cloths on the roof around the chimney keep it perfectly clean.
Rebuilding the chimney using new brick, the right masonry cement, and a level.
Based on the heat, humidity, and wind of the day, we might pre-soak bricks to keep them from drawing water from the cement. Cement strength improves with lower water-cement ratios, but we don't want the brick to absorb the water from the cement.
A custom form for the new cap, extending over the sides by the 2 inches required by code.
The black rain and critter cover is installed on the fireplace flue. It should be large and open enough to allow the flue to vent properly.
The red tape covers a rope that will cause an indentation around the bottom of the cap, forming a drip-edge that prevents water from running underneath the cap to the bricks.
The tape makes it easy to remove the form without the cement bonding to the rope.
Rebar or mesh is placed in the cap help reduce shrinkage and thermal cracking.