How to Measure Your Drain

Name: How to Measure Your Drain
Uploaded: 2026-11-04
Duration: 1 min 28 s
Description: How to measure a floor drain for a Green Drain waterless trap seal: lift the grate, measure the pipe below the drain body inside wall to inside wall, take two readings at right angles, match the smaller one to a size, then press the seal in and see how to take it out.

Before you order, measure the one width that sets your Green Drain size: the pipe below the drain body, inside wall to inside wall. Not the grate and not the top of the body: both are wider than the pipe. This video shows where to measure, how to read it, and how the seal goes in and comes out.

How to measure your drain. The video measures a 3 in floor drain; the reading from your own pipe sets your size.

Match your reading to a size

Each size seats in its own range of pipe openings. On the edge of two, either one fits. The installation guide has the full size chart, and the measuring tool reads the size straight off the drain.

GD151.5 in pipe, 39 to 47 mm GD22 in pipe, 51 to 59 mm GD252.5 in pipe, 55 to 65 mm GD33 in pipe, 68 to 81 mm GD353.5 in pipe, 89 to 95 mm GD44 in pipe, 99 to 107 mm GD55 in pipe, 125 to 133 mm GD66 in pipe, 149 to 157 mm