Roofers use the term flashing, when talking about the thin metal sheet used to direct water away from certain elements on the rooftop. Those are usually protrusions, such as a chimney or skylight. Yet those thin metallic sheets might also be used in one of the roof’s valleys, or over top of joints and seams.
It limits the chances for development of leaks. A majority of leaks form in spots where a contractor has failed to install an adequate level of flashing. A general contractor for Roof Repair in San Mateo does not have all the skill and training of a roofer. Some contractors agree to place a roof on an addition, without knowing anything about the need for thin metal sheets/flashing.
Types of metal used to form the thin sheets
• Stainless steel
• Galvanized steel
Some building codes specify the type of metal that should be used in any flashing; the same codes could also set a standard for the flashing’s thickness.
If a contractor or roofer were to ignore the details in the code, the building inspector would not certify the completed addition. As a result, the homeowner could struggle to find a buyer, if he/she chose to try selling the altered home.
Spots where a contractor should use flashing
Where the roof’s surface comes in contact with a wall
Where there are protrusions on the rooftop.
Where 2 of a roof’s low points come together
At the low edges of roofing: A roofer/contractor should place the thin metal sheets under the shingles.
Why might a contractor fail to recognize the need for flashing’s presence in a given area?
In a spot where something has protruded upward from the roof’s surface, there might not be any visible gaps. Still, there could be very thin cracks in the region where the protrusion has come in contact with the roofing.
Similarly, in a spot where 2 of a roof’s low points have come together, it is possible that the same low region could be gap-free. Still, that fact would not rule out the possible existence of a thin crack. Only a thin metal sheet would do a good job of hiding that crack, without marring the beauty of the rooftop.
A contractor might not understand how low the edge of a roof must be, in order to require flashing’s placement under the shingles that line that same edge. In that case, something worse than a leak could develop.
Water would slowly and repeatedly wash over the roof’s unprotected edge. Hence, it would gradually start to deteriorate. Obviously, no one wants to live a house with where the roof’s edges have begun to deteriorate. They could even break from the roofing.