A roof leak around a plumbing vent pipe is usually a cracked rubber pipe boot. The rubber collar dries out in the sun and splits, and rain runs down the pipe into the attic and ceiling. Loose or rusted nails around the boot, or a boot installed on top of the shingles instead of woven under them, cause the rest. Replacing the boot is a small repair.
Signs the vent pipe is the source
- A round stain on the ceiling of a bathroom, kitchen or laundry room
- Water running down the pipe in the attic
- Daylight around the pipe when you look up from the attic
- A gray, cracked or split rubber collar on the roof
- Nail heads rusted or popped up beside the boot
Why pipe boots fail
The rubber sits in full sun every day. Pine Bluff averages about 23 days a year above 95 degrees, and the roof surface gets much hotter than the air. That dries the rubber until it cracks, usually on the uphill side where water hits first. Many boots fail around 8 to 12 years, often before the shingles around them. Squirrels chewing the rubber is another cause we see.
Other vent leaks
Bathroom exhaust vents, box vents and furnace flue pipes can leak at their flashing or caps too. Ridge vents along the peak are a separate case: see ridge cap and ridge vent repair.
The fix
The old boot and nails come out, a new boot is slid under the shingles above it and over the shingles below, and the fasteners are sealed. If the decking around the pipe is soft from a long leak, it gets replaced. It is one of the quickest roof repairs. See roof vent and pipe boot repair and pipe boot replacement cost.
Can I fix it from inside?
No. The water gets in at the roof, so the fix has to happen on the roof. From inside you can only catch the drip and dry things out.
Should all the boots be replaced?
If one boot has cracked, the others on the same roof are the same age. Replacing them all in one visit usually saves a second trip later. See how long pipe boots last.
How do I check my pipe boots from the ground?
Zoom in with your phone camera or use binoculars on the pipes sticking out of the roof. A healthy boot is dark and smooth. A failing one looks gray, cracked or split, and sometimes the rubber collar has pulled away from the pipe. Look for dark streaks on the shingles right below the pipe, too. If you have a two-story home or a steep roof, a photo is the safest way to check.
Are there better boots than rubber?
Yes. Lead boots and boots with a metal base and a replaceable rubber collar last longer in the sun than all-rubber boots. For homes with squirrels or lots of sun exposure, they are often worth the small extra cost. We will tell you which ones make sense for your roof.
What if water still comes in after a new boot?
Then the leak may be elsewhere, often flashing or a nail uphill of the pipe, with water running down to the pipe before it drips. See why a roof still leaks after a repair.
Why does my bathroom ceiling leak when it rains?
There is usually a plumbing vent pipe right above the bathroom, and a cracked boot around it lets rain in.
Can I put caulk around a leaking vent pipe?
It may slow it for a season. A new boot is the lasting fix and costs little more.
How long do vent pipe boots last?
Many last about 8 to 12 years in the Arkansas sun.
Is a vent pipe leak covered by insurance?
Usually not, since boots wear out with age.