Sold under many names

Sill pan

A waterproof tray set under the window at the bottom of the opening that catches any water getting past the window and drains it back outside.

What it means for you

One of the most important invisible parts of an install, and one of the first things a cheap job skips. Without it, wind-driven NC rain that sneaks in has nowhere to go but the wall and subfloor. Ask whether the opening gets a sill pan on a full-frame job.

Where you'll see it

Buried under the window on a proper full-frame install; almost never an itemized line.

Also sold as: sill pan flashing

Related terms

Defined by Marc Hanley

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