Data Center Infrastructure Accessories
How to measure a raised-floor cut-out for a replacement brush grommet
Five measurements that decide whether a split grommet fits an existing tile cut-out — and how to send them with an RFQ.
Updated: 27 September 2026
Why measure first
Floor grommets are sold by cut-out size and usable cable opening. Legacy halls often have cut-outs made by hand in different sizes, so a “standard” grommet may not cover the hole, or may leave too little room for the cables already in it.
The five measurements
| # | Measure | Why it matters |
|---|---|---|
| 1 | Cut-out length × width (mm) | The grommet frame must overlap the hole on all sides |
| 2 | Corner radius or round diameter | Rectangular vs. round frames; sharp corners need edge protection |
| 3 | Tile thickness and tile covering | Determines flange vs. recessed mounting and screw/adhesive fixing |
| 4 | Cable bundle cross-section (approx.) | The usable opening must pass the existing and planned cables |
| 5 | Distance to tile edge / pedestal | A frame larger than the cut-out must not overhang the tile edge |
Choosing the grommet type
| Situation | Suitable type |
|---|---|
| Cables already installed, standard rectangular cut-out | Split rectangular grommet |
| Round core-drilled hole | Round grommet of the matching diameter |
| Long slot along a row of racks | Long split grommet or brush strip frame |
| Non-standard hand-cut hole | Custom frame made to the measured size |
| Rough or sharp edges | Add edge protector strips |
What to send with the RFQ
The five measurements (a photo with a tape measure helps), quantity per size, preferred frame material, and whether split installation is required. We match the size to a standard frame where possible and quote a custom frame only when needed.
Keep expectations realistic
Grommets reduce air leakage through cable openings; the overall effect depends on the complete air-management strategy (blanking, containment, gap sealing). We do not quote energy-saving percentages for a single product.
Frequently asked questions
What is the difference between cut-out size and usable opening?
The cut-out is the hole in the tile the frame must cover; the usable opening is the brushed area available for cables inside the frame.
Can one grommet size fit several cut-outs?
Yes, if the frame overlaps each cut-out fully and the usable opening is large enough — group your measurements by size range in the RFQ.
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