Brick chimney repair with metal flashings
Older homes may need chimney repairs. Common issues include:
- Rotted roof sheathings under shingles;
- Expired metal flashings cause roof leaks
Any rotted roof sheathings must be replaced because they can no longer support the weight of the shingles, nor can they hold nails.
Cricket is a wood saddle used to redirect water from the high point of a roof, preventing pooling. We recommend installing a cricket when a chimney is wider than 24" and the roof pitch is 6/12 or greater, and where snow and ice accumulations are likely.
Flashings are sheet metals installed to ensure the roof-to-deck connection is watertight. They also allow for some chimney/roof movement. Flashings may last a long time, but they eventually expire and may cause roof leaks.
There are two types of metal flashings: base and step flashings are secured to the roof deck against the front vertical chimney wall and on the side and back walls. In colder climates that experience heavy snow, ice or heavy winds, we also recommend installing a waterproofing membrane around the base of the chimney (and up the walls too) before installing flashings.
Counter flashings are the second type. They are secured to the chimney and act as a "cap" on top of the base and step flashings. Counter flashings can be installed by cutting out a mortar joint to a depth of 1.5" and inserting the bent edge of the flashing into the cleared joint. Some brickworks may be required after the counter flashings are installed.
A large chimney repair costs $1,000 to $2,000. Cricket costs $400 per chimney.