Roof sewer vents can leak rain water down into your walls for years
Every home has them but homeowners and even some professionals rarely think to look them over and apply an easy fix.
They are roof vents mostly used for sewer vent pipes. Homes will have them sprouting up across the roof line.
Most are only sealed by a simple rubber gasket, which will eventually dry rot from long hot summers.
Since most of these pipes center in the walls leading up through the attic space from plumbing fixtures, rain water can leak in for years without any noticeable signs from the inside.
The picture at the bottom fortunately showed up as a paint blister, it was attributed to water leaking in around the sewer vent located in the same area.
Since the vent pipe flanges or flashing's are raised the main rain runoff from the roof is sealed off. It is the rain that hits the pipe directly that runs down through the dry rotted opening.
Just think of the amount of water that runs down the side of a flag pole during a heavy rain. Without the rubber seal no longer stopping it, the water continues to run down into the walls of the house.
This moisture can accumulate inside the drywall and create mold issues for the home.
The rubber seal can be easily caulked around using a high grade clear silicone caulk and then checked each year after.
Badly deteriorated gaskets can be covered by purchasing a new flange and cutting the gasket out with a sharp knife then adding clear silicone and slipping it over the pipe down to cover the top of the old seal.
New flanges can be purchased at any home center and are made to fit pipe size ranges.
Since the flange slides up under the shingles and then is layered an nailed in with the shingles it is not a good idea to try and replace the flange as shingle damage may occur making the situation worse than just the gasket.
If you have an older home you may have a lead flange that covers the sewer pipe and then is bent over and inside the pipe.
These are better than the rubber seal but do also crack open with age. Those cracks can be sealed with silicone as well.
A simple walk across the roof each fall will help spot these issues as well as other flashing problems around fire places and additions.