Commercial electrical contractors - bid on a real scope

What is commercial electrical service?

Commercial electrical work covers service and distribution equipment, three-phase power, lighting and controls, life-safety and emergency systems, and the fit-out work that follows every tenant change. The difference from residential is not the wiring - it is the procurement. Work is bought against a written scope, delivered inside operational windows that suit the building rather than the crew, and governed by a contract that says who carries the risk when something is found behind a wall.

Signs you need commercial electrical service

• A tenant improvement or fit-out where the existing distribution has to serve a use it was not designed for
• Recurring nuisance trips, voltage complaints or equipment faults that nobody has ever traced to a root cause
• Distribution equipment that is obsolete, unsupported, or for which replacement parts are no longer manufactured
• A lighting retrofit driven by energy cost, a utility incentive programme, or a lease obligation
• Adding load the service was never sized for: EV charging, kitchen equipment, server or network rooms, production machinery
• No arc-flash study on file, no current one-line diagram, and nobody who can say what feeds what

Seeing something not on this list? Browse electrical problems by symptom →

How commercial electrical service actually works

1. 1

   Establish what you are actually buying against

   The single largest cost driver in commercial electrical procurement is scope quality. A bid against a drawing set and a specification is comparable; a bid against a walkthrough and a conversation is a guess that will be corrected by change order. Where no design exists, buy the design first - from an engineer or a design-build contractor - and then bid the work.

   Watch forThree bids with a wide spread. That is almost never three views of the same job; it is three different interpretations of an ambiguous scope. Reconcile the assumptions before comparing the numbers.

2. 2

   Survey the existing conditions

   Service size and available capacity, the age and support status of the distribution equipment, the accuracy of the one-line diagram, panel schedules that reflect reality, and whether an arc-flash study exists and is current. In older buildings the documentation is usually wrong, and finding that out during construction is expensive.

   Watch forPanel schedules taken at face value. In most commercial buildings they are a decade out of date, and a de-energisation planned from them takes down something nobody expected.

3. 3

   Agree the work window and the shutdown plan

   Occupied buildings dictate when work happens: nights, weekends, phased areas, or short planned outages with an agreed restoration time. This drives labour cost more than almost anything else in the estimate, and it needs to be stated in the scope rather than discovered by the crew on their first shift.

   Watch forA day-rate bid on a job that can only be done at night. It will be the lowest number you receive and it will not survive contact with your tenants.

4. 4

   Confirm the labour and compliance position

   Public work, and some private work, carries prevailing wage obligations that materially change the labour rate. Alongside that: licensing in the jurisdiction, insurance limits and additional-insured status, bonding where required, safety record, and any site induction or background requirements the building imposes.

   Watch forA bid that has not priced prevailing wage on a job that requires it. It is not a saving - it is a bid that has to be re-priced or a compliance problem later.

5. 5

   Closeout and the documents you keep

   As-built drawings, updated one-line and panel schedules, an updated arc-flash study where equipment changed, warranty documentation, commissioning and test records, and the permit sign-off. These are what make the next project cheaper, and they are the first thing dropped when a job runs late.

   Watch forRetention released before closeout documents are delivered. It is the only leverage that reliably produces them.

What does commercial electrical service cost?

Commercial work is priced by scope, access and hours rather than by any published rate. The variables that move it most are the work window, the labour classification, and how much of the existing installation has to be surveyed or corrected before new work can land. Bid at least three contractors against one written scope.

See the full commercial electrical service cost guide - by material, size and region →

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