Flat Roof Drain Repair

A roof drain is more than a hole in the membrane — it’s a fitting that connects the roof surface to the building’s plumbing, usually with a clamping ring that seals the membrane to the drain body. Over decades, that seal can crack, the drain bowl can corrode, or the drain line itself can become disconnected below the roof surface.

Signs you need drain repair rather than just cleaning: water still pools around the drain even when it’s clear of debris, you can see cracking or rust at the drain bowl, or water is tracking down into the building near the drain location rather than through the pipe. On older Downey homes with built-up (BUR) roofing, drain bowls installed decades ago are a common failure point simply due to age.

Repair typically involves resealing or replacing the clamping ring and surrounding membrane, or in more serious cases, replacing the drain assembly itself. This is different from a simple cleaning — if the drain hardware itself has failed, no amount of clearing debris will stop the leak.

Signs the Drain Itself Needs Repair, Not Just Cleaning

A cracked clamping ring, visible rust or corrosion on the drain bowl, or water tracking down into the building specifically at the drain location even when it’s clear of debris are all signs the hardware itself has failed, not just gotten clogged. On older BUR roofs especially, original drain assemblies installed decades ago are common candidates for this kind of age-related failure.

Repairing a failed drain properly means resealing or replacing the clamping ring and surrounding membrane collar, and in more serious cases, replacing the drain body itself — a bigger job than clearing debris, but often still far less extensive than a full re-roof.