Chimney cricket flashing. Installing new copper flashing and chimney cricket support on a large brick chimney.
The finished flashing. The copper sheet metal has been cut and fabricated to fit the wood framing of the chimney cricket. The roof side of the flashing is extended 14 inches up the roof slope under the roofing shingles. the roof shingles are cut back from the cricket/roof flashing bend to prevent leaves and debris from clogging the area and holding water.
Next to the chimney the flashing extends 3 inches up the back of the chimney. The chimney counter flashing has been cut and bent with a lip at the top edge that fits into the old groove cut into the brick chimney mortar. This counter flashing is secured in place with copper nails and then sealed with a high quality bronze colored urethane sealant.
New wood framing for the cricket flashing.
A new plywood frame has been installed behind the brick chimney. This is basically just two triangles cut to fit the roof slope needed to facilitate good water runoff from behind the chimney. A single rafter is installed under the plywood to support the structure. Tarpaper underlayment is installed over the wood decking. Roof shingles and new sub copper flashings are installed first and then the copper cricket flashing. Copper counter flashing is installed over the base flashing.
The original chimney flashing.
Excessive tarring of chimney flashing is often found where roofers are capable enough to install the field shingles, but are incapable of installing flashings at roof penetrations such as this chimney. In this case the previous roofers removed the existing roof shingles but left, and flashed right over, the original chimney flashing. The saddle flashing they used is actually a length of flashing intended to be used for a roof valley intersection.