Roof Leak? Here's What To Do Before the Crew Arrives

An active leak is a race against water damage. Every hour it runs, it soaks more insulation, drywall, and framing. Here is what to do while help is on the way.

Contain it first

1. Put a bucket or bin under the drip and move furniture and electronics clear.
2. If a ceiling is bulging with trapped water, carefully puncture a small hole at the low point to let it drain into a bucket in a controlled way, rather than letting the whole ceiling collapse.
3. Pull back wet carpet and get air moving with fans to slow mold growth.
4. Photograph everything before you clean it up, for insurance.

Finding the source is harder than it looks

Water rarely enters directly above where it drips. It travels along rafters and decking, sometimes many feet, before it finds a place to fall. That is why chasing a leak from inside the house is unreliable, and why the actual entry point is usually somewhere upslope.

The most common entry points are not holes in the middle of the roof field. They are transitions and penetrations:

• ▸Flashing around chimneys, skylights, and wall intersections.
• ▸Plumbing vent boots, whose rubber gaskets crack from UV over time.
• ▸Valleys where two roof planes meet and water concentrates.
• ▸Roof edges and drip edge details.
• ▸Fasteners that backed out or were overdriven at install.

Repair or replace?

A repair usually makes sense when the roof is relatively young, the damage is isolated, and the rest of the system is sound. Replacement starts making more sense when the roof is near end of life, leaks are appearing in multiple places, or the decking has been compromised.

Be cautious of anyone who recommends a full replacement without getting on the roof, and equally cautious of anyone who patches repeatedly without ever discussing the underlying condition.