An E-Room is the largest single fabricated item on most campuses and the one with the most interfaces. Buying it well means deciding early who owns the shell, who owns the gear, and who tests the two together.
Sourcing E-Rooms 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.
- Decide the split of scope first: shell only, shell plus fit-out, or shell with equipment installed and factory-tested.
- The RFQ needs the single-line, equipment layout, site loads and transport route, not just a floor plan.
- Qualify on structural and sheet-metal capability under one roof plus electrical assembly experience; a shell bought from a building supplier is a different product.
- Schedule value comes from factory testing before shipment; write the witness points into the PO.
What you are buying
An E-Room, E-House or power control room is a transportable building with a welded structural base, insulated metal walls and roof, doors, HVAC, lighting and grounding, and the medium- and low-voltage switchgear, transformers, panels and bus duct installed inside. For procurement the critical decision is where the scope line falls. A shell package covers the base, envelope, openings and interior mounting steel. A fit-out package adds cable tray, grounding bus, lighting and HVAC. An integrated package has the owner-furnished or fabricator-procured electrical gear set, landed and point-to-point tested before the unit leaves the plant. Each line moves risk and schedule in a different direction, and the RFQ should name the one you want.
Where it sits in the project
E-Rooms sit at the power block or electrical yard, one per hall or per megawatt block, and on substation sites as control and relay houses. They are bought by the developer or EPC early, usually right after the switchgear order, because the room has to be detailed around the gear's certified drawings. Electrical contractors receive them, set them and make final terminations. If the room is late, energization is late; if the gear is late, the room waits.
What to put in the RFQ
| Scope line | Shell only, shell plus fit-out, or integrated with equipment installed and tested; who procures the gear |
|---|---|
| Equipment basis | Single-line diagram, equipment list and the OEM's certified drawings or preliminary outlines |
| Layout | Plan with working clearances, door swings, bus and cable entry locations, raised floor or cable vault |
| Site loads | Wind, snow, seismic category and foundation concept (piers, slab or skid) |
| Envelope | Panel type and R-value, roof system, door and louver schedule, fire and smoke requirements |
| Transport | Route limits (height, width, weight), shipping splits allowed, lifting method |
| Testing | Factory acceptance tests, witness points, water-tightness and door-seal checks |
| Documentation | Structural calcs if stamped drawings are required, material certs, lifting plan, as-built drawings |
How to qualify a fabricator
- One shop for the base, the walls and the enclosures. Fabricators who buy the shell from a modular-building supplier add a layer of markup and a layer of interfaces.
- Electrical assembly experience. Ask who lands the bus and wires the panels, and whether that crew works in the same plant.
- Proof of fit-up. A trial fit of the gear before the walls close is the difference between a room that bolts up on site and one that needs a field crew.
- Lifting and transport engineering. Lifting lugs, spreader-bar plans and shipping splits should be designed, not improvised at the dock.
Lead time, sequencing and delivery
The room is only on the critical path if it is released late. Release the shell once the gear's outline drawings are frozen; the fit-out can proceed while the switchgear is in production, and the gear is set the week it arrives at the fabricator. Agree a factory acceptance test date in the PO and send a witness. Transport is a day; setting is a day; terminations are the electrical contractor's.
Common mistakes
- Buying the shell before the gear is frozen. A room detailed around nominal dimensions is redrawn when the certified drawings arrive.
- Leaving transport to the end. A room that does not fit the route is split at the last minute, in the wrong place.
- No witness points. Factory testing you did not see is a report, not a test.
- Splitting shell and fit-out across two vendors. Every penetration becomes a coordination item.
How FabTek supplies it
FabTek fabricates E-Rooms and electrical houses from the base frame to the equipment-installed unit at four plants in Hazlehurst, Mississippi. The structural base, the insulated shell, the switchgear enclosures and the bus duct housings inside come from the same floor, and owner-furnished gear is set and landed where the project specifies it. Related modular options are power skids and containerized units.
Frequently asked questions
What is the difference between an E-Room and an E-House?
The terms are used interchangeably: a prefabricated, transportable electrical building with switchgear and power equipment installed inside. Utilities tend to say control house or E-House; data center teams say E-Room or power control room.
Who should buy the E-Room, the developer or the electrical contractor?
Most developers buy the room with the switchgear as owner-furnished equipment so it can be released before the electrical contractor is on site. The contractor sets it and makes final terminations.
How long does it take to set a prefabricated E-Room?
Typically a day to lift and set on prepared piers, and days rather than weeks to connect, because the interior is already wired and tested.
Can FabTek build an E-Room around another OEM's switchgear?
Yes. FabTek details the shell to the OEM's certified drawings and either ships the shell to the OEM for fit-out or installs the OEM's gear in Mississippi.
