Four trades hanging four sets of rods over the same row is the slowest way to build a ceiling. A unified grid or prefabricated multi-trade racks is one package, detailed once and hung once.
Sourcing overhead support grid for a data center project? Call 601.892.5017 or email collin.t@fabtekindustries.com — send the drawings and the spec and we quote to print.
- Buy the grid as one package from the coordinated model, owned by the GC or developer, not trade by trade.
- The fabricator needs the BIM or support layout with hanger spacing to the busway and tray manufacturers' requirements.
- Qualify on fabrication from the model, pre-assembly and tagging by grid line.
- Seismic bracing is part of the grid; specify it in the same RFQ.
What you are buying
Above a data hall's rows, busway, cable tray, ladder rack, fiber tray, cooling pipe, containment and lighting all hang from structure. A unified overhead support grid is one structure, strut or HSS, spanning between building members with hanger points at coordinated spacing; multi-trade racks are pre-assembled trapeze sections with the busway hangers, tray supports and pipe saddles already installed. Both are fabricated from the coordinated model and tagged to the grid line. Attachment hardware, headers for heavy loads and seismic braces come with them.
Where it sits in the project
GCs and developers buy the grid to take it off the trade contractors' critical path; electrical and mechanical contractors buy prefabricated rack sections to cut hanging time. The grid goes in after structure and before any service is hung, so it releases as soon as the coordinated model is signed off.
What to put in the RFQ
| Coordinated model | BIM export or support layout with service routing and hanger spacing by system |
|---|---|
| Loads | Busway, tray, pipe, containment and lighting loads per the engineer; seismic category |
| Grid type | Strut, HSS, welded trapeze and header, or hybrid; attachment to deck, beams or inserts |
| Pre-assembly | Which hangers, saddles and brackets are installed in the shop; section lengths |
| Finish | Pre-galvanized strut, hot-dip galvanized steel, or powder coat for exposed grid |
| Seismic | Brace assemblies and attachments per the stamped details |
| Tagging | Grid line and row on every section; delivery sequence by row |
How to qualify a fabricator
- Model-based fabrication. Ask how the shop takes the BIM and holds hanger spacing to the busway and tray manufacturers' requirements.
- Pre-assembly and tagging. Sections built, hangers installed, every piece labeled by grid line.
- Structural and strut work in one shop. Heavy headers and light strut on the same section.
- Related support scopes. A fabricator who builds the tray supports, busway hangers and pipe supports can carry the grid.
Lead time, sequencing and delivery
Release the grid from the signed-off coordinated model, by hall. Sections ship in grid-line order with the attachment hardware and seismic braces for that row. Later halls release against the retained model and tags.
Common mistakes
- Grid bought trade by trade. That is four sets of rods again, just in strut.
- Hanger spacing from a sketch. Spacing comes from the busway and tray manufacturers.
- Seismic bracing left to the field. It belongs on the grid drawings.
- No tags. A thousand identical sections with no grid line is a sorting project.
How FabTek supplies it
FabTek fabricates overhead support grids and multi-trade racks from the coordinated model at four plants in Hazlehurst, Mississippi, with the cable tray supports, busway hangers, pipe supports and seismic bracing it carries built on the same floor and tagged by grid line.
Frequently asked questions
What is an overhead support grid in a data center?
A unified structure hung from the building frame above the rows that carries busway, cable tray, piping, containment and lighting on one set of supports instead of separate trade-by-trade hangers.
What is a multi-trade rack?
A prefabricated trapeze or rack section with the hangers and supports for several trades already installed, so it is hung once and the services are set into it.
Who should buy the overhead grid?
Usually the GC or developer, as one package from the coordinated model, so it comes off the trade contractors' critical path and the hanger spacing is coordinated once.
Who fabricates multi-trade racks for data centers?
FabTek Industries fabricates overhead grids and prefabricated multi-trade rack sections at its Mississippi plants for GCs, developers and electrical and mechanical contractors.
