Measuring Round Grates

Round drains: Physical dimensions required for recommending and installing Fabco Industries water quality filter inserts

Step 1:

The first measurement required is the DIAMETER of the Grate. Following this measurement you need to remove the GRATE from the FRAME


Step 2:

Next we need to measure the DIAMETER of the CLEAR SPACE inside the GRATE support ledge. A close up of the GRATE SUPPORT LEDGE is shown in Image 3. The Fabco water quality insert features a circular supporting flange that is designed to fit on this ledge. The maximum diameter of this support flange needs to be slightly less than the diameter of the grate. And the Physical diameter of our filter must be less than the area of the CLEAR SPACE. The unit hangs down inside this clear space.


Step 3:

The circular GRATE SUPPORT LEDGE supports the Fabco unit. Once the Fabco unit is in place, the grate is re-installed directly on top of the Fabco unit. Any water entering the grate will be directed to the Fabco filter.


Step 4: This image shows the bottom surface of the grate.

In most cases cast grates have ribbing on the bottom surface that extends downward. This ribbing provides extra load bearing strength. In this image the rib is central and is located next to the tape measure. There are variations of ribbing. In some cases every bar or every other bar extends downward. 3 points are critical to us 1) Is there ribbing 2) Does the rib height tapper to the grate edge like the one shown or does it hold its’ height from edge to edge and 3) measure the distance from the rib edge to the outside edge of the grate. In the photo this is about 1”

The last measurement required is depth – we need 30” for cartridge units (StormPod) and a minimum 15” for filter bag units (StormSoks)