Extra work in a contractor agreement: how not to overpay
Approval, the estimate, and certificates — so “just a bit more” does not become a second contract
In contracting, money disputes most often come from extra work: the contractor did it “in fact”, the customer never signed, the estimate ballooned. A general checklist is how to check a contractor agreement. Below is only the extra-work block: what must be in the text before the first shovel.
This is a guide, not legal advice. Building codes, public procurement, and sector rules may set a separate change procedure.
The contractor sent an addendum or a new estimate — compare it with the original version, or check the whole contract for risks:
What counts as extra work
Extra work is volume beyond the statement of work / estimate / specification, without which the result cannot be finished, or which the customer requested separately. If the subject is vague (“works as agreed”), almost anything can be called extra work — and a dispute is guaranteed.
- Is there a clear SOW and a boundary of “what is in / what is out”
- Fixed price or “estimate + actuals” — different change logic
- Hidden works: who bears the risk of unforeseen volumes
The approval procedure is the heart of protection
1. Written consent before start
The most common conflict: the work is already done, and there was no consent. Fix in the contract: extra work starts only after written approval (addendum, order, EDI) with price and deadline. An oral “yes, do it” is a weak evidence base.
2. The customer’s reply deadline
The contractor needs a deadline: silence for N days ≠ automatic consent unless you agreed that. For the customer, “no reply means approved” without a sum cap is dangerous.
3. Emergency / urgent work
Allow a narrow list of situations where the contractor may act without prior consent (collapse risk, utility cut-off), with notice within 24 hours and a sum cap. Otherwise “emergency” becomes a hole in the budget.
Price, deadline, certificates
- How extra-work price is calculated: estimate rates, a price list, a market valuation
- Whether the overall contract deadline and the penalty shift
- A separate certificate for extra work or inclusion in the general certificate
- The customer’s right to refuse extra work and the effect on the result
On cost escalation and force majeure in contracting — force majeure and cost increases.
A 10-minute checklist
- The SOW and estimate fence off the base scope
- Extra work only after written approval of price and deadline
- No “silent consent” without a cap
- The emergency track is narrow and with notice
- It is clear how the deadline and the penalty change
- Extra-work certificates are not mixed into the base with no trail
Related reading
Short conclusion
Extra work without a procedure is the main estimate inflater. Fix written approval, the price method, and certificates — and “just a bit more” stops being a surprise at the end.
Check a contractor agreement in DocumentCHEK
Upload the contract or addendum — get a review of extra-work terms and one-sided wording.