How to track construction change orders

Missed change orders are the single largest preventable source of margin loss on residential builds. The pattern is consistent: a sub does extra work without a signed CO, the work happens, an invoice arrives with the extra on it, the GC pays it because the work was done, and there's no authorization to bill the homeowner. The cost gets stuck on the GC's P&L.

A single missed CO of $5,000-$8,000 wipes out the margin on most residential trade scopes. Across 15-25 trades on a typical custom home build, even a 5% miss rate amounts to tens of thousands of dollars in unbilled work per year. The seven-step process below cuts the miss rate to near zero.

Step 1 — Require written change requests before work begins. The single most important discipline. No verbal approvals, no nodding on site. Every scope change must be documented in writing before any work proceeds — even small changes. Many GCs put this directly in their subcontract: invoices for extra work without a corresponding signed CO will not be paid.

Step 2 — Price the change order with line-item detail. Use AIA G701 or your own change order form. Break out direct labor, direct materials, indirect costs, overhead, profit, and schedule impact. Lump-sum change orders are a red flag — they hide markup and make later verification impossible.

Step 3 — Get all parties to sign before work proceeds. Contractor, owner (or owner's representative), and architect where applicable. If the scope change is urgent and can't wait for full pricing, issue a Construction Change Directive (CCD) that authorizes work to start but defers final price. Then convert the CCD to a signed CO within days, not weeks.

Step 4 — Log the change order against the project budget. Update your project budget immediately when the CO is signed. The original contract value becomes the contract value plus the sum of all approved COs. Most importantly, update the schedule of values (your G703) so subsequent draws reflect the new total contract value.

Step 5 — Track cumulative CO impact in real time. Twelve small COs across the project, each one reasonable, can quietly push a $1.4M contract to $1.62M before anyone notices. Maintain a running total visible to the team — original contract + approved COs + pending CCDs — so the surprise never happens. Cumulative CO impact above 8-10% of contract value should trigger a project-level review.

Step 6 — Verify sub invoices reference approved COs only. When a sub invoice references work outside the original quote, verify a signed CO exists on file for exactly that work. Hold payment until the CO is signed. This is where the discipline of steps 1-5 actually shows up in dollars saved.

Step 7 — Close out every CO before final retainage release. Final payment and retainage release should require that every approved CO has been billed in full, paid, and matched to a signed lien waiver. Open or unbilled COs at substantial completion become disputes.

1. Verbal change orders on site. The most common — and most expensive — mistake. PM agrees to upgraded fixtures in the master bath during a walkthrough. Three weeks later the plumber invoices for it. No paperwork.

2. Late CO pricing. Work proceeds while pricing is "still being worked out." When the price comes in higher than expected, the owner pushes back but the work is already done. Always lock the price before mobilization.

3. Forgotten cumulative impact. Each individual CO seems small. Nobody adds them up until the final draw, by which point the owner is surprised by the new total and the leverage is gone.

4. CCDs that never convert. A change directive authorizes work to start but defers price agreement. Without discipline, the CCD never converts to a formal CO and the work gets paid on invoice without proper authorization paperwork.

Ella reads every change order that lands in your project inbox — AIA G701, custom forms, or plain email. She extracts CO number, description, price impact, schedule impact, and signature status. She maintains running totals per project. When a sub invoice references work outside the original quote, she checks for an approved CO on file and holds payment until the CO is signed. See change order verification for the full feature breakdown.