Example of Dormer Flashing Repair
What We Do
These dormers were leaking into the upstairs bedroom because the flashing had rusted out. Our solution was to replace all the dormer flashing with new copper flashing to keep the roof in working order.
First we extracted all the slate bordering the dormers. Then we installed ice and water shield around the dormers for protection if it rained while we worked. Then we custom fabricated metal flashing to replace the old flashing.
Metal flashing on dormers consists of the apron flashing at the bottom of the dormer, the step flashing running up the sides of the dormer, and the valleys on top of the dormer.
On this job the aprons were inset which required custom folding to allow for expansion and contraction. Also this inset flashing had to be retrofitted without taking out the window sill or trim.
The ship lap siding acted as counter flashing to prevent the water from riding behind the step flashing.
We double folded the valley at the seam and installed it using cleats to allow for expansion and contraction of the metal. This also prvents putting nail holes through the valley pans where water can enter. The copper cleats are locked onto the hem also called a slater’s edge, to prevent water from running laterally over the valley.
Because of the complexity of these dormers, this project lasted for two weeks.