Construction Dispute Adjudication in Ontario: A Decision in Weeks, Not Years

A payment dispute can stall a project for months — or kill it. The contractor says the extra work is done and billed; the owner says it was never approved. The subcontractor hasn’t been paid in 90 days. The work is finished, the money isn’t moving, and everyone is talking about lawyers and liens.

Ontario has a faster route for exactly this: adjudication. Since October 1, 2019, most construction contracts in Ontario carry a right to have a payment dispute decided by an independent adjudicator — in weeks, not years. Here’s how it works, when it fits, and where it goes wrong.

What adjudication is

Adjudication is a fast, interim-binding dispute process under Ontario’s Construction Act, run through ODACC — the Ontario Dispute Adjudication for Construction Contracts, the body the Act names to appoint adjudicators.

The key word is interim-binding: the adjudicator’s decision must be followed right away, even though either side can still take the same dispute to court or arbitration later for a final answer. In practice, most adjudication decisions stand — by the time a court could hear it, the project has moved on and the money has already done its work.

It is not a court case. There are no years of discovery, no trial, and no $100,000 legal bill to chase a $40,000 payment.

What disputes it covers

Adjudication is built for the disputes that actually stop projects:

Valuation of work — what the work done is worth, including disputed extras and change orders
Payment — progress payments not made, or made short, under the contract
Change orders — whether an extra was authorized, and what it should be paid at
Delay — who caused it, and what it cost
Set-off claims — an owner withholding payment for alleged defects or incomplete work

Owners, contractors, subcontractors, and suppliers can all start one. The contract doesn’t need a special adjudication clause — the right comes from the Act itself.

How it works, step by step

Notice of adjudication. The party starting it serves a written notice on the other side: who the parties are, what the dispute is, what outcome is being asked for, and the contract details.
An adjudicator is appointed. ODACC appoints one, usually within a week. Adjudicators are experienced construction professionals — engineers, quantity surveyors, senior contractors, and construction lawyers.
Both sides make their case. The adjudicator sets a tight schedule: documents, a short written submission from each side, sometimes a brief hearing or site visit. No drawn-out process — this is the point.
A decision, fast. The adjudicator aims to decide within 30 days of receiving the documents. The parties can agree to more time if the case is complex.
The decision is followed. The losing side pays or performs as ordered. If they don’t, the decision can be filed with the court and enforced like a court order.

The adjudicator’s fee is shared between the parties unless the adjudicator orders otherwise — another reason to keep the claim tight and well documented.

A case from my own files: the homeowner who won — and still had to chase payment

Sharon, a Toronto homeowner, hired Home Guru Inc. (Justin Brooks and Aaron Zon) for underpinning, waterproofing, a walkout, drains, and a window well. The subcontractor who did the waterproofing work was paid in full — $179,215.74 including HST across five 2024 invoices — while the work itself was deficient and incomplete: the walkout stairs didn’t meet the Building Code (the city inspector confirmed the risers and treads failed OBC 9.8.4.4), no warranty was ever given, and the remaining work couldn’t proceed until the foundational defects were fixed. The project stalled, the site was left in disrepair, and the contractor refused to fix what it had admitted was deficient.

Sharon took it to adjudication — ODACC case #5910. The adjudicator’s findings were blunt:

Home Guru had used “a classic form of bait and switch” to win the contract
It had failed “to obtain competitive quotes from subcontract bidders and to account for the amount of deficient work observed on site”
It had “exhibited sufficient bad faith conduct on this project”
The valuation of its work and what Sharon had paid were “excessive”

The award: $94,796.94 to Sharon.

And here is the part most people don’t expect: winning the adjudication was only half the job. Home Guru refused to pay. The determination was entered at the Superior Court as a court order (file CV25007427080000), and enforcement — against the company’s assets and its directors — had to be pursued next.

The lessons from this case are the ones I give every client:

Adjudication gets you a fast, binding decision — weeks, not years, and on documents, not drama.
A win still has to be collected. Filing the determination with the court turns it into an enforceable order, and knowing the other side’s assets before you start matters.
The paper trail wins cases. Deficiencies documented, code failures confirmed with the inspector, invoices itemized — that record is what the adjudicator decided on.

When adjudication is the right move — and when it isn’t

Adjudication fits when:

The dispute is about money owed, extras, or delay — and the project needs to keep moving
The amount matters but doesn’t justify a full court case
You have documents: a contract, invoices, change orders, photos, daily logs, emails
Cash flow is the problem — a subcontractor waiting 90 days, a contractor carrying an owner’s project

Think twice when:

The dispute turns on a deep legal question (a novel contract interpretation, a fraud allegation) — that’s court or arbitration territory
You have almost no paper trail — adjudication is fast, which means it rewards whoever documented the job
The other side is insolvent — a decision against a party with no money is a decision you can’t collect

The traps that cost people their case

Waiting too long. Adjudication doesn’t replace your lien rights — in Ontario you still have 60 days from the contract’s completion, abandonment, or termination to preserve a lien, and 90 days after that preservation window closes to perfect it — but the clock on every remedy runs at once. Get advice early, not after the lien deadline has passed.
Stopping work in anger. Walking off the job can turn you from the wronged party into the party in breach. Adjudication exists precisely so work can continue while the money dispute is decided.
Undocumented extras. “He told me to just do it” is the most expensive sentence in construction. If it isn’t written, signed, and priced, adjudication will treat it as disputed — and it is.
The prompt-payment clock. Under the Act, an owner must pay a proper invoice within 28 days; a contractor must pay its subcontractors within 7 days of being paid. Knowing where you stand on that clock shapes the whole dispute.

How I help

An honest read of the dispute first: is adjudication the right forum, or is it negotiation, a lien, or a lawyer’s file?
Getting the paper in order — contract, invoices, change orders, photos, logs — so the case is built on documents, not memory
Preparing the notice and the submission, and helping you choose what to claim and what to leave out
Coordinating with a construction lawyer where the dispute needs one — I know where coaching ends and legal advice begins

This page is practical guidance, not legal advice. For large or legally complex disputes, a construction lawyer should review the case before you file.

Start with your free hour

Unpaid, underpaid, or stuck in a dispute that’s stalling the job? Call 1-888-688-8864 or contact The Reno Coach before the next invoice goes out — an hour now will tell you which route fits, and what your case needs to stand up.