Tendering Commercial Electrical Projects: A Practical Walkthrough

Quoting a $400 callout and tendering a $2M commercial fitout are not the same job. The fundamentals are similar (labour rate, materials, margin), but project tendering adds layers that catch out sparkies moving up from service work.

This is the walkthrough. Same system taught inside the Estimating Masterclass.

1. Read every page, twice

Commercial tender documents come with drawings, specs, schedules, and a tender response form. Read all of it. Then read it again.

What to look for:

• Drawings vs spec mismatches. The drawings say one thing, the spec says another. Tender questions exist for a reason.
• Tender clauses. Liquidated damages, defects liability, retention, payment terms. They all affect price.
• Hidden scope. Sub-mains, RCDs, emergency lighting, smoke alarms, testing & tagging. Easy to miss on a busy drawing set.
• Exclusions language. What’s in the head contractor’s scope? What’s in the electrical contractor’s? What’s a grey area?

Two passes minimum. Take notes on the second pass.

2. Do a proper take-off

A take-off is the count of every billable item in the documents.

A practical workflow:

• Mark every drawing with a colour-coded count: lights, GPOs, switches, data, RCDs, etc.
• Use a take-off template, not a blank page. The same categories every time.
• Cross-check the schedule against the drawings. Whichever has more, query.

TradieTally’s project estimating tools include a structured take-off workflow that organises this the way an electrical estimator actually thinks about it.

3. Labour production rates

Project labour is not service labour. The minutes-per-task numbers are different. You’re rarely on a clean site, and crew sizes change the maths.

Common rates (rough, Australian commercial):

• Single GPO install in commercial: 25-35 minutes including testing
• 2400×600 LED panel fit: 35-45 minutes
• Standard distribution board: 4-6 hours per single-phase board
• Sub-main termination: depends on size, expect 2-4 hours per termination

These are production rates. Add prelims, supervision and contingency on top.

4. Prelims: the bit that gets forgotten

Prelims are everything that isn’t bolted to the wall:

• Site supervision
• Site induction time
• Programme attendance
• Scaffold access (or lack of)
• After-hours work (if specced)
• Compliance documentation
• Final defects sweep
• Testing & commissioning

Skip these and your margin disappears before the first invoice.

5. Margin, contingency and the bid

Project margin is lower than service margin, typically 12-20%. Add a contingency on top (5-10% depending on risk) and you’ve got your sell price.

A clean tender:

• Labour total (production hours × rate)
• Materials total (with margin)
• Prelims total
• Subbie costs (with margin)
• Margin on the lot
• Contingency on top

Run it through the Electrical Estimating System page for the full breakdown, or do it inside TradieTally’s project workflow.

6. Qualifications and exclusions

Your tender response should include clear qualifications:

• What’s specifically included
• What’s specifically excluded (e.g. data cabling above 6m heights, energy management commissioning, etc.)
• Assumptions (single-phase mains, standard ceiling type, free-issued switchboard)
• Variation handling clause
• Programme assumptions

A clean qualifications page protects margin if the head contractor pushes scope creep.

7. The follow-through

You won the tender. Now keep the margin.

• Log every variation the moment it happens.
• Submit progress claims on time, fully detailed.
• Final account chase starts before the job finishes.

TradieTally Business Brain shows project profitability live. You see margin slipping while you can still fix it, not at end-of-job.

The full system

The Estimating Masterclass covers each of these in depth, with templates for tender responses, variation registers, and progress claims. Stack it with the Estimating Fundamentals Course for the labour-rate and margin foundation underneath.

Project tenders are won on accuracy and lost on margin. Both come from the same system.