Cracked pipe boots and vent leaks fixed in Vancouver, WA

Every roof has several openings for plumbing vents, bath and kitchen exhaust fans, attic vents and sometimes furnace or water heater flues. Each one is sealed with a boot, collar or vent cap that has to keep water out for as long as the shingles last. Many do not. Rubber pipe boots dry out and crack in the sun, plastic vent caps get brittle, and exposed nails around them back out over time.

Pipe boot and roof vent repair is often a quick fix with a big payoff. We replace the failed boot or vent, weave the new flashing into the shingles correctly, and seal the fasteners. While we are on the roof, we check every other opening, because if one boot has cracked, the others of the same age are usually close behind. Replacing them together saves a second trip.

Why pipe boots and vents fail

Most pipe boots are a metal or plastic base with a rubber collar that hugs the vent pipe. The rubber is exposed to sun every day, and over years it dries, shrinks and cracks, often well before the shingles around it wear out. Once the collar splits, water runs straight down the outside of the pipe and into the attic. On many Vancouver homes, the original boots fail long before the roof does.

Box vents and exhaust caps fail differently. Plastic vent hoods get brittle and crack, especially on south and west slopes that take the most sun. Metal vent caps rust at the seams. Dampers on bath and kitchen fan caps stick open, letting wind-driven rain in. And the nails holding vents down can back out, lifting the shingle above them and leaving a hole that drips every time it rains. Each one is a small, cheap fix.

What we replace and how

For pipe boots, we lift the shingles around the boot, remove the old one, slide on a new boot sized to the pipe, and weave its base into the shingles so the upper part sits under the course above and the lower part sits on top. For vents and exhaust caps, we follow the same lapping rule. All fasteners are placed where the next course covers them, and any exposed heads are sealed.

• Rubber-collar or all-metal pipe boots
• Lead boots for older cast iron vent stacks
• Box vents and ridge-adjacent attic vents
• Bath and kitchen exhaust caps with dampers
• Storm collars on furnace and water heater flues

Choosing longer-lasting boots

Standard rubber-collar boots are inexpensive but can crack in sunny exposures within a decade or so. Upgraded options include boots with thicker, UV-resistant collars, all-metal boots with a separate sealing gasket, and soft lead boots that fold over the top of the pipe. Lead boots last a long time but can attract squirrels that chew them. We explain the options and recommend what fits your roof and budget. There is no single best boot.

For bath and kitchen exhaust, we use caps with working backdraft dampers sized to the duct. A cap that is too small restricts airflow, and moisture then condenses in the duct and drips back into the attic, which can look like a roof leak. If we find a bath fan venting straight into the attic instead of through the roof, we point it out, since that causes moisture problems of its own.

Replacing boots during other roof work

If you are planning a roof replacement soon, there is no need to replace boots separately, since all new flashing goes in with the new roof. But if the roof has years left, replacing every aging boot at once makes sense. It costs less per boot than calling us out one at a time, and it stops the pattern of a new leak every winter as each boot fails in turn.