Electrical estimating for data center construction

If you have estimated electrical work for offices or warehouses, a data center will feel familiar for about ten minutes. The lighting and receptacles are there. Then you reach the one-line diagram and the scale of the power system takes over: medium voltage service, paralleled generators, UPS rooms, battery space, and busway running over every row of racks. Electrical is the largest scope on most of these projects, and it is where an estimate can go wrong in the most expensive way.

This guide covers what a data center electrical estimate includes, how the takeoff differs from conventional work, and where assumptions need to be written down. It gives no unit rates, since gear pricing is moving too quickly for a fixed number to stay useful. For the budget view, see what data centers cost to build in 2026.

The power path, from the utility to the rack

The easiest way to organize the estimate is to follow the power. Start at the utility service: the incoming medium voltage feed, any on-site substation, and the main switchgear. Next comes standby power, which means generators, fuel systems, paralleling gear and transfer equipment. Then the UPS systems and batteries, which condition the power and carry the load during the gap before generators start.

From there power is distributed through low voltage switchboards, panelboards, power distribution units and remote power panels or busway to the racks. Grounding and bonding run through everything. Finally there are the building loads that every project has, including lighting, receptacles, fire alarm and controls, plus the monitoring systems that report on electrical health.

How the takeoff differs from conventional electrical work

Counting devices is a small share of the work. The heavy measuring is in feeders, busway and cable tray. Large feeders are expensive per foot, and a data center has many of them, often in parallel sets. Small routing assumptions change totals a lot, so the estimator has to lay out the routes, measure them, and carry the terminations, supports and fire-stopping that go with them.

Equipment needs a different approach. A generator or a switchgear lineup is a purchased item with a quote, a delivery window and a rigging plan. The estimate needs the equipment price, the cost to set and connect it, and any testing. Our post on electrical takeoff scope and deliverables shows how a conventional package is organized, and how to estimate electrical work covers pricing basics.

Where the price risk sits

Switchgear is a good example. The Cushman and Wakefield 2026 development cost guide reported switchgear costs up about 60% between December 2021 and early 2026. Skanska’s Summer 2026 report put generator price increases at 8% to 10% for 2026 and noted that demand for generators of 2 MW and larger is absorbing a large share of manufacturing capacity. Copper and aluminum add to cable and busway cost. If the estimate hides these exposures inside a unit rate, nobody sees them until the bid is lost or won.

The practical fix is to break major equipment out as separate lines with quote dates and validity periods, and to price cable and busway with a stated commodity assumption. The post on long-lead equipment explains how to handle delivery risk, and tariffs and estimate assumptions covers the pricing side.

Scope boundaries that need to be written down

• Who supplies and who installs the major equipment, and whether owner-furnished items are shown.
• The point where the utility’s work ends and yours begins, including any transformer and metering.
• Whether the UPS batteries are included, and whether battery rooms have separate ventilation or fire protection scope.
• Testing and commissioning, including load bank testing for generators and integrated systems tests.
• Temporary power during construction.

Most disputes on these projects trace back to a boundary that was assumed, not stated.

Labor and schedule

Electricians are in demand in the markets where data centers cluster. AGC’s 2026 workforce survey, run with NCCER, found 88% of firms with craft openings reporting positions as hard or harder to fill than a year earlier. Productivity assumptions that were fine two years ago may not hold, and the labor estimating guide shows how to document those assumptions.

Common questions

What makes data center electrical estimating different?

Scale and equipment. Feeders, busway and major gear dominate cost, and the equipment is purchased with long lead times and volatile prices.

Is electrical the biggest part of a data center budget?

In most published breakdowns, electrical and mechanical systems together outweigh the building. Exact shares depend on the design.

Should equipment be priced from catalogs?

Use dated vendor quotes. Catalog or historical prices go stale quickly for switchgear, generators and UPS systems.

Getting the electrical takeoff done

Measuring feeders, tray, busway and equipment from a large drawing set takes time that bid teams often do not have. Our electrical estimation service handles the takeoff and pricing from your drawings, and our MEP estimation service covers the mechanical and plumbing scopes alongside it. Send us the set and we will quote the work.