Chimney crown replacement and repair across Edgewater

When cracks run through the crown

A crack that runs from the flue to the outer edge may go through the full depth of the crown. Water can then travel down into the chimney. Pieces may also shift or lift as the crack widens.

Through-cracks change the repair. Filling the surface line does not rejoin the concrete underneath, and coatings are meant for sound material. We tap and inspect the sections on either side. When the crown is split into loose pieces, replacement is usually the honest recommendation, and we explain why.

Shrinkage cracks in new crown concrete

Concrete shrinks as it cures. Brick industry guidance treats shrinkage of a cast-in-place crown as a certainty and calls for reinforcement to help control it. Fine cracks on an older crown may date back to that original cure.

We explain the difference between old shrinkage lines and cracks that are active and growing. On a new crown, reinforcement and curing care are part of the plan. If you notice fine lines on a new crown later, tell us so we can look at them against what was expected.

Layers of old patches on a crown

Some crowns carry several patches from different visits. Each layer may be a different material, and they do not always bond to each other. Water can travel between layers and appear somewhere unexpected.

Tell us what you know about earlier crown work, even if it is only a rough idea. We assess whether the layers can stay or need to come off. A new product applied over a stack of failing patches can only perform as well as the weakest layer underneath it.

Conditions that decide sealing or replacement

The choice between coating and a new crown comes down to a few conditions. We check each one on your chimney and explain what we found.

When all of these hold, a coating may be a sensible repair. When one or more fails, a coating would cover a problem it cannot solve, and we explain replacement instead.

• The concrete is firm and still attached to the brick
• The crown slopes away from every flue
• The edges keep real thickness and overhang the face
• The joint at each flue can be resealed