How to Bid Commercial Jobs for General Contractors

Bidding commercial subcontract work for general contractors is a different skill set from writing residential estimates. The scope is larger, the documentation requirements are stricter, the competition is more sophisticated, and the margin for error is smaller. But the payoff is proportional - a single commercial bid win can be worth months of residential work. Before any of that matters, you first have to get invited to bid on commercial projects in the first place.

Here is how to bid these jobs the right way.

Understand the Bid Documents First

Before you start any takeoff or estimate, read the bid documents completely. Commercial projects typically include:

Plans and specifications: The architectural and engineering drawings that define what needs to be built
Division specifications (spec book): Detailed written requirements for materials, installation standards, and testing
Invitation to bid: The scope, bid due date, required documentation, and submission format
Addenda: Any changes issued after the original bid documents are released

Many subs skip the spec book and go straight to the plans. This is how you miss a specification that requires a specific brand of equipment, a particular insulation rating, or a testing protocol that adds cost. Read the specs for your division before you estimate.

If anything in the documents is unclear, submit an RFI (request for information) through the GC before the bid deadline. Do not assume.

Take Off the Work Systematically

A takeoff is the process of quantifying exactly what materials and labor the job requires. For commercial bids, this needs to be systematic and documented.

Work section by section through the plans. Measure pipe runs, count fixtures, calculate ductwork square footage, note equipment specifications. Keep a running spreadsheet that tracks what you found on each sheet of the plans. This documentation matters if there is a scope dispute later.

Common takeoff mistakes that kill margins:

Missing equipment shown on detail sheets but not on the main plan
Undercounting pipe runs that go through complex wall configurations
Forgetting to include seismic bracing, insulation, or other spec-required items
Not accounting for material waste and over-order percentages

Build waste factors into your takeoff based on your trade. Pipe typically runs 10-15% waste. Ductwork can run higher depending on the job.

Build Your Estimate in Layers

Structure your estimate so you can see exactly where the money is:

Materials: Actual quoted cost from your supplier for this specific job. Do not use rule-of-thumb material costs on commercial bids - call your supplier and get pricing on the specified equipment and materials.

Labor: Hours by task, multiplied by your fully burdened labor rate (base wage plus taxes, insurance, benefits, and overhead per hour). If you do not know your fully burdened rate, calculate it before you bid a single commercial job.

Subcontractors: If you are sub-bidding any work to your own subs (crane services, specialized testing, etc.), get written quotes before you submit.

Overhead and profit: Add your overhead percentage to cover the portion of your fixed costs allocated to this job, then add your profit margin. Commercial work typically runs 10-20% overhead and 8-15% profit depending on your market and job type.

Price for Risk, Not Just Cost

Commercial bids have more risk factors than residential work. Price accordingly:

Schedule risk: If the GC's project schedule is tight or unclear, add contingency for overtime or accelerated work. If you are not sure whether you can hit the rough-in date with your current crew size, factor in the cost of adding temporary labor.

Coordination complexity: On large commercial jobs with many trades, coordination issues are inevitable. You will lose time to delays caused by other subs. Price accordingly.

Change order risk: Complex commercial projects almost always generate change orders. Make sure your contract includes a mechanism for fair change order pricing, and do not price your base bid low expecting to make it up in changes - this strategy fails more often than it works.

Submit a Clean, Complete Bid Package

Your bid submission signals your professionalism as much as the number itself, and it should match what GCs expect in commercial project documentation. At minimum, include:

A cover letter with your company information and bid summary
An itemized cost breakdown by labor and materials
Exclusions and clarifications (what is NOT included)
Your proposed schedule for your scope
Current license and insurance certificates
A list of references from similar commercial projects

GCs who receive complete, well-organized bids take those subs more seriously. A bid that is just a number on a scrap of paper goes in the pile of unknowns.

Follow Up on Every Bid

Call the GC within 24 hours of submitting your bid to confirm receipt and ask if they need any clarification. This call keeps your name in front of the project manager at the moment they are evaluating bids.

If you do not win the bid, ask why. What was the winning bid? Were there scope differences? Was it purely price? This information makes your next bid sharper. The right way to follow up after a commercial bid is as much a part of your win rate as the number itself.

Your Action Step

Find one commercial project going out to bid in your market in the next 30 days. Contact the GC, request the bid documents, and go through the process end to end even if you are not sure you will win. The practice of doing a full commercial takeoff and building a layered estimate is how you develop the skill to compete for this work consistently.