How to Evaluate a Building’s Electrical Capacity

Electricity reaches your desk through a series of components, each with its own limit. Power comes from the utility into the building’s service equipment, passes through main switchgear, travels up the building in risers or bus duct, lands at distribution equipment serving your floor, feeds the panels in or near your suite, and finally runs out through individual circuits to outlets and equipment.

A building can have a large utility service and still be unable to deliver more power to a particular floor, because the riser serving that floor is fully committed or the floor’s panels are full. A suite can have spare room in its panel and still have no way to add load, because the equipment upstream is at its limit. When a landlord says the building has plenty of power, the useful follow-up is: where in the chain, and available to whom?

This guide does not give sizing rules. The power your team needs depends on your specific equipment and how it is used, and the building’s real capacity depends on its design and what other tenants already draw. Both are jobs for a licensed electrical engineer, not for a rule of thumb.

An engineer cannot evaluate a building without knowing what you plan to plug in. Before touring, have your IT or hardware lead assemble an inventory.

• Every category of equipment: standard workstations, GPU workstations, servers, storage, network gear, lab and test equipment, charging stations, kitchen appliances.
• The nameplate electrical data for each significant item, taken from the manufacturer’s documentation.
• Any equipment with special requirements, such as a voltage or phase configuration that differs from standard office outlets, or a dedicated circuit.
• Which loads run continuously and which run only during working hours.
• Where the load will be concentrated: one server room, a lab, or spread across the open office.
• Planned growth over the lease term, including equipment you expect to add after a funding round or a new product line.

Your engineer turns this into a load estimate with appropriate allowances. Cooling equipment is part of the electrical picture too. A supplemental cooling unit for a server room draws power itself, so the electrical and mechanical questions have to be answered together.

Ask for documents, not adjectives. A landlord with a well-run building can usually produce most of these through its chief engineer or its outside engineering firm.

• ✓The building’s electrical one-line (or riser) diagram, showing the service, switchgear, risers and distribution to each floor.
• ✓Panel schedules for the panels that serve our premises, showing which circuits are in use and which spaces are spare.
• ✓The capacity currently allocated to our premises, and how the lease will state it.
• ✓Recent measured demand for the building and, if available, for the riser or floor serving us, so spare capacity is based on readings and not only on design.
• ✓Whether any capacity on our riser is reserved for other tenants or for future landlord use.
• ✓The age and condition of the main electrical equipment, and any planned replacement or shutdown during our term.
• ✓How electricity to our suite is metered: direct utility meter, landlord submeter, or included in rent or operating expenses.
• ✓The building’s rules for tenant electrical work, including required contractors and review fees.
• ✓The landlord engineer’s written response to our load estimate.

Drawings on file are not always current. Buildings change over decades of tenant work, and panel schedules are often handwritten and out of date. Your engineer should walk the space, open the panels with building staff present, and confirm that what is on paper matches what is installed.

If the landlord cannot or will not produce electrical drawings and load data during the proposal stage, treat that as information about how the building is run.

Several people will have opinions about power. They do not carry equal weight.

• The leasing broker for the building can tell you what the marketing materials say. That is a starting point, not verification.
• The building’s chief engineer knows how the systems actually behave and where the limits are. Ask to speak with this person directly.
• The landlord’s electrical engineer can confirm base building capacity and review your plans, but works for the landlord.
• Your own electrical engineer, typically part of the engineering team working with your architect, is the person who should compare your load to the building’s capacity and sign off.
• The electric utility decides whether more power can be brought to the building, on what schedule, and at whose cost.

Engage your engineer before you sign a letter of intent on a space where power is a real requirement. A short review at the shortlist stage costs far less than discovering a shortfall after the lease is executed.

A shortfall does not always end the conversation. It does turn into a question of scope, cost and time, and the answers differ by where in the chain the limit sits.

• Circuits and panels within the suite. Adding circuits or a panel is ordinary build-out work and is usually the easiest fix.
• Distribution to the floor. Running a new feeder from the building’s main equipment requires riser space, landlord approval and more construction.
• Building switchgear. If the main equipment is at its limit, an upgrade affects the whole building and is the landlord’s decision.
• Utility service. Bringing more power to the building involves the utility’s engineering, equipment and schedule. Timing is outside the control of both landlord and tenant, and it can be long.

The further upstream the constraint, the more the schedule becomes the risk. If your occupancy date depends on a utility upgrade, ask your attorney about tying rent commencement or a termination right to the power actually being delivered.

Cost is negotiable. Depending on your leverage and how much the upgrade benefits the building after you leave, it may be paid by the landlord as base building work, drawn from your tenant improvement allowance, or paid by you directly. An upgrade to building infrastructure that stays with the property is a fair candidate for landlord funding. Also ask whether you must remove any of it at the end of the term.

Once your engineer is satisfied, the finding has to be fixed in the documents, because capacity that is available today can be allocated to another tenant tomorrow.

1. State the electrical capacity committed to your premises in the lease, in the terms your engineer recommends.
2. Add a right to install additional circuits, panels and feeders, with landlord consent not unreasonably withheld, and a defined path through the risers.
3. Record who pays for each upgrade and who owns and maintains it.
4. Confirm the metering method and the rate basis for electricity charges, so heavy use does not trigger a discretionary surcharge.
5. If you expect to grow, ask for a right to additional capacity later, or at least a commitment that the landlord will not allocate away the spare capacity your engineer identified.
6. Address planned shutdowns: notice, timing outside your working hours, and coordination with your equipment.
7. Have your attorney review the language and your engineer review the technical exhibit.

Tenant Advisory Group represents tenants and buyers, and for technology companies with meaningful power needs we send electrical questions with the request for proposal so that buildings are compared on documented capacity before anyone falls for a floor plan.