I’m still surprised when conducting my home inspections at how often I find examples of incorrectly installed flashing. “Flashing” is normally installed around window and door openings, and is made of a variety of material, but flashing is also required on many roof applications. Whenever a pitched section of roofing abuts a wall (or other vertical surface), flashing must be provided.
When installing roof shingles, the flashing is normally referred to as “step flashing,”and each course of roofing material has a piece of step flashing installed over the current course of roofing material and then against the adjacent wall. Step flashing is normally comprised of pieces of “L” sheet metal, but the key to a proper installation is to have the upper portion of the “L” flashing placed against the framing or sheathing of the abutting wall, and this is the important part…under the siding or stucco cover.
To save time and effort, some installers fail to remove the wall cover, and instead, place the L flashing against the wall cover. This defeats the purpose of the flashing, which is to prevent any rain water from getting behind the flashing and into the framing. The attached photos, taken at a 1930’s era home in the East Bay, depict how the flashing is actually placed on top of the stucco. This has resulted in gaps between the flashing and the stucco, and this is a direct pathway for rain water to enter the framing.
Directly below this roof section is a badly cracked and damaged section of stucco that is clearly water-damaged. And this damage is a direct result of the improper flashing. This home has mold growth problems related to a variety of issues, but one of the most obvious (and serious) issues concerns this roof flashing. And until this flashing is removed and re-installed correctly, this section of roof will continue to leak every time it rains!