The argument over whether something was “always in the job” or a chargeable extra almost never turns on who remembers correctly. It turns on who wrote it down.
Key takeaways
Most disputes start the same way: a homeowner or GC looks at a final invoice and doesn't recognize a line item, while the trade insists the item was always going to cost extra. Treadstone Law's framing of this fight is that the client “changed the scope” — asked for upgraded materials, added rooms, or requested work beyond the original plan — and the real question is whether that change was priced and agreed before the work happened, not after.
A quote and an estimate are not the same document, and the distinction matters more than most people building a scope description realize: a quote is generally treated as the fixed price for a defined scope, while an estimate is understood as approximate. Vague scope wording is what turns a legitimate extra into a dispute, because neither side can point to language that clearly puts the disputed item on one side of the line or the other.
Extras are rarely proposed in a calm moment. Treadstone Law's guidance on change-order disputes lists three recurring triggers: a contractor billing for work that was never discussed, a genuine disagreement about whether an item was already inside the original scope, and unforeseen site conditions discovered mid-project. All three share the same weakness — the price and scope of the extra get settled verbally, under time pressure, with no one writing it down.
The advice on both sides of the relationship points the same direction. For an owner, the guidance is blunt: “Do Not Agree to Anything Verbally On-Site Under Pressure” — ask for it in writing and take time to review it before a price increase gets waved through. For a trade wanting to get paid for real extra work, the same discipline runs the other way: get the ask, the price and the go-ahead in writing before the tools come out.
An unforeseen site condition sits in a slightly different category from a simple scope change, but it produces the same kind of argument. Unforeseen conditions discovered during the work are one of the three recurring triggers for a change-order dispute, precisely because nobody planned for them and nobody priced them in advance. The fact that a condition was genuinely unforeseeable doesn't automatically make the resulting cost an approved extra — it still has to go through the same written-agreement step once it's discovered, ideally before work continues past the point where the condition was found.
A change order, defined plainly, is “an agreed modification to the original contract — a change in scope, materials, price, or timeline, documented and (ideally) signed by both parties before the additional work begins.” That definition does three things a verbal instruction can't: it fixes what changed, it fixes what it costs, and it fixes when the change takes effect.
On a CCDC 2 project this isn't left to whatever paperwork the parties improvise. CCDC 16 — A Guide to Changes in the Contract is the companion document CCDC publishes specifically to explain “the philosophy to changes embodied within CCDC documents, including key terms, the change process, methods for adjusting the contract price, and claims.” The general conditions text and clause numbers behind that process sit in the paid CCDC 2 document itself, but the existence of a formal, named process is the point: a CCDC 2 project is not supposed to settle extras by memory — a discipline worth understanding fully before signing the prime contract in the first place.
A missing signature doesn't automatically kill a legitimate claim, but it shifts the whole argument onto whatever record does exist. Courts look for anything in writing — a text, an email, a signed form — showing agreement to the extra work, and weigh that against how specifically the original contract described the scope and whether the disputed work was necessary or purely discretionary. A verbal agreement “can be” enforceable, but it is harder to prove, and disputes over what was actually said are common.
The practical fallback, on either side of the disagreement, is the same move: put your position in writing as soon as the dispute surfaces — what you agreed to pay, and why you believe (or don't believe) the additional charge is owed — rather than letting the disagreement sit undocumented until it reaches a demand letter. Where the original wording is genuinely ambiguous about what was included, Ontario courts tend to interpret an ambiguous clause against the party who drafted it, which is one more reason a trade writing its own scope language has an incentive to make that language specific.
A worked example
A kitchen renovation quote lists “supply and install cabinetry per attached drawing” at a fixed price. Mid-project, the homeowner asks for a change to soft-close hinges and an added pantry cabinet not on the drawing. The contractor proceeds the same week and invoices an extra $2,800.00 at completion.
The homeowner disputes it: nothing was signed, and the email thread only shows the contractor saying “sure, can do” to a text message, with no price mentioned before the work started. The contractor's strongest available evidence is that same text thread, plus a follow-up photo sent to the homeowner showing the new cabinet mid-install with no objection raised at the time. That record is weaker than a signed change order would have been, but it is far stronger than an invoice produced with no contemporaneous documentation at all — and it is the difference between a defensible claim and an unrecoverable one.
It can support a claim, but it is a weaker position than a signed change order, and disputes over what was actually said are common. The safer move on either side is to confirm the ask and the price in writing — even a same-day text or email — before work starts.
That still helps, but it raises a separate question about whether the rep actually had authority to approve extras on the owner's behalf. Writing that down at the time — who approved it, when, and in what words — is what lets the point be argued later; relying on memory does not.
Yes in structure, not in principle. CCDC 2 builds procedures for changes in the work directly into the prime contract, with CCDC 16 explaining the change process, price-adjustment methods and claims that sit behind it. A one-page trade quote has no equivalent built-in process, so the parties have to create the same discipline themselves.
Sometimes refusing isn't realistic on an active site, but the least-risky version is a written confirmation of scope and price sent before or immediately after starting — not an invoice line produced weeks later with nothing to point back to.
No. It's one of the recurring reasons change-order disputes arise, but the condition still has to be documented and priced through the same written process as any other extra. Discovering a real problem doesn't skip the paperwork step — if anything, an unusual or unexpected condition is exactly the kind of item worth pausing to confirm in writing before continuing.
Yes. A project's supplementary conditions can shorten the notice window or add extra sign-off steps for a change order beyond what the general conditions alone would require, which is one more reason to read those project-specific terms before assuming the standard change process applies unmodified.
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