Estimating practice
The 10 Elements of an Electrical Estimate
A single blended rate is a summary, not an estimate. Here is the elemental structure behind a defensible electrical number — and the specific trap waiting in each element.
Ask three cost professionals for an electrical rate and you will get three numbers, all of them defensible, none of them comparable. The reason is almost never the market. It is structure: what each of them included, and what they assumed someone else was carrying.
A blended dollar-per-square-foot rate is the summary of an estimate, not the estimate itself. Here is the build-up that sits behind a number worth defending, and the trap that lives in each element.
1. Service and distribution
Incoming service, transformers, switchgear, panels, feeders, grounding — the backbone everything else hangs off.
The trap: it carries the longest lead times on the job. Price the gear and the wait.
2. Power and devices
Branch wiring, receptacles, motor control centres, equipment connections, electric heating connections, VFD supply.
The trap: it looks routine, so it gets benchmarked lazily. Device density varies wildly by building use.
3. Lighting and controls
Luminaires, lighting controls, emergency and exit lighting, exterior building lighting.
The trap: controls complexity has quietly doubled. Yesterday's rate will not hold.
4. Standby and emergency power
Generators, UPS, transfer switches, essential distribution.
The trap: in hospitals and data centers this is effectively a parallel building. Never carry it as a percentage.
5. Fire alarm
Detection, notification, monitoring, verification.
The trap: scope is set by code and authority-having-jurisdiction interpretation, not by the drawings you priced.
6. ELV and communications
Structured cabling, communications rooms, AV, distributed antenna systems.
The trap: it sits between contractors and vendors — the "by others" orphan breeds here, and integration labour appears on no drawing.
7. Security and access control
Access control, CCTV, intrusion detection.
The trap: device counts multiply with every design review, and the cost of making systems talk to each other is rarely priced.
8. Special systems
Sector-specific scope: nurse call, SCADA, traction power interfaces.
The trap: generalist benchmarks miss these entirely. This is precisely where building types diverge.
9. Site and exterior electrical
Site lighting, ductbanks, the utility interface.
The trap: the utility connection is a negotiation with a timeline you do not control.
10. Testing and commissioning
Integrated systems testing, energization support.
The trap: the specialists are among the scarcest resources in the market. A percentage allowance is a wish, not an estimate.
The build-up IS the estimate. The rate is just its summary — and a summary you cannot decompose is a summary you cannot defend.
Why the structure matters more than the numbers
Two consultants can measure the same drawings and produce the same quantities. The one who can decompose their rate into named elements, each with a stated assumption, wins every reconciliation — because when the numbers diverge, the conversation becomes forensic rather than adversarial.
Most estimate disputes I have refereed dissolve once scope boundaries are mapped. One firm carried gear under equipment; another under subcontract. Site-wide distribution sat in different elements. The apparent gap in judgment was mostly taxonomy.
Put this into practice
I built a free electrical cost toolkit around these principles — an elemental build-up with estimate-class ranges, a named risk register, compound escalation and a $/kW density check.
Open the free toolkit →