This is not the first time I have written about the installation of roof pipe flashings that are not “consistent” with the expected life of the roof.
The types of pipe flashings that I am talking about are the ones that have a stretch-rubber component designed to fit tightly against the sides of the pipe. They may be constructed entirely of this stretch rubber material or a combination of harder plastic materials or metal materials. All three of these types of flashings have about a 15 year life expectancy making them suitable for roofs designed to last that long. These types of flashings should not be used with any of the many other types of roofs designed to last a lot longer than that.
This first picture is of the “metal/rubber” type pipe flashing installed on a roof designed to last 20-30 years (note also that it is the wrong size flashing for the size of the pipe).
This next picture is of the “all rubber” type pipe flashing installed on a metal roof designed to last 50 years or more.
So far, these flashings have not “failed” because the roofs they are installed on are still less than 15 years old. The other day, the house I inspected had the “plastic/rubber” type pipe flashings installed—-and they were failing. The flashings and the roof were 15 years old. The roof has a design life of 25-35 years. Here are a couple of pictures of two of six flashings on that roof.
You might ask, “Well, yeah, but how much water can actually get in there?” The answer is quite a lot—-enough to do significant damage over time—-not to mention a place where insects and other vermin can get into the roof structure.
Charles Buell, Seattle Home Inspector
If you enjoyed this post, and would like to get notices of new posts to my blog, please subscribe via email in the little box to the right. I promise NO spamming of your email