Corbelworks · Field Tools

FAQ — Scope-Creep & Change Order Cost Calculator

Real answers about pricing change orders, stopping scope creep, and protecting profit when the job grows beyond the contract.

Updated August 2026 · 5 questions

Frequently Asked Questions

How do I price a construction change order?

Do not just price materials plus hours. Add admin time (quoting, scheduling, approval), schedule delay (crew standing idle), overhead recovery, and margin.

Example: $500 materials, 4 hrs at $85/hr = $840 direct. Add 2 hrs admin at $85 = $170, delay cost $200, overhead 15%, 20% margin → $1,511 not $840.

Without the admin, delay, and overhead, you would have billed $840 and eaten $671 of cost. The calculator shows this breakdown so nothing is missed.

What is scope creep and how much does it cost?

Scope creep is unapproved work expansion — the customer asks for small additions that individually seem trivial but accumulate into significant unbillable labor and materials.

NACE International estimates rework and scope changes cost 10–15% of project value. For a $50,000 job, that is $5,000–$7,500 in unbillable work if not managed with a change-order process.
Should change orders have a higher markup than the base contract?

Yes, typically. Change orders disrupt schedule, add admin burden, and carry higher risk of dispute. 25–35% margin on change orders vs 15–20% on the base contract is common.

You are pricing disruption, not just materials and labor. A change order pulled mid-project means re-mobilizing, re-scheduling, and often idle time for the crew that was on the next job. That cost belongs in the change order price.

How do I stop scope creep before it starts?

Four things:

1. Written scope with explicit exclusions — if it is not listed, it is not included.

2. A change-order process clause in the contract: any work outside the scope requires a signed change order before crews begin.

3. Site approval required before extra work begins — the foreman cannot say yes on their own.

4. A written change-order signature before crews start.

Verbal "just while you're here" requests eat profit faster than any other leak.
What if the customer refuses to sign a change order?

Stop work on the changed scope. Document the request in writing — email, text, or a change-order form with a refusal note. Do not proceed on good faith.

In most states, "they said they'd pay" is uncollectable without a signed change order or written agreement. If the customer will not sign, that is your signal that the work is disputed.

Proceeding anyway converts a scope disagreement into a free upgrade. Stop, document, and escalate to the contract's dispute resolution clause.