Using a Deficiency Holdback Clause in Your Renovation Contract in Ontario

Most homeowners have heard that Ontario law requires a percentage of a construction contract to be held back before final payment. Far fewer realize that this statutory requirement isn't actually designed to protect them against deficiencies — and that they can negotiate a separate, additional holdback in their own contract that does exactly that.

A well-drafted deficiency holdback clause in a renovation contract gives an Ontario homeowner real leverage to get problems fixed after substantial completion, instead of chasing a contractor who has already been paid in full.

The Statutory Holdback: What the Law Already Requires

The Construction Act requires that a percentage of the contract price — 10% of the price of the services or materials supplied, as of mid-2026 — be held back rather than paid out immediately (verify the current figure before relying on it, since it's set by statute and can change). This holdback exists mainly to protect the lien rights of unpaid subcontractors and suppliers further down the supply chain, giving them a window to register a claim against the property if they're not paid, before the money is released.

For longer projects, Ontario now also requires periodic, annual release of holdback rather than holding the full amount back until the very end. The mechanics of that annual release process are technical and time-sensitive — if your renovation spans more than a year, ask a lawyer how the annual release rules apply to your specific contract rather than trying to work it out from general articles like this one.

The Key Misconception: The Statutory Holdback Isn't "Your" Deficiency Fund

It's tempting to assume the statutory holdback is there to protect you against deficiencies in the finished work. It generally isn't — its purpose is upstream, protecting subcontractors and suppliers within the construction pyramid, not giving the homeowner leverage to force deficiency repairs. If you want that kind of protection specifically for yourself, it has to come from your own contract.

What a "Deficiency Holdback" Clause Adds

A deficiency holdback clause is a separate, private contract term: the owner agrees to retain an additional amount — on top of, and separate from, the statutory holdback — until an agreed list of deficiencies identified at substantial completion has been fixed. Because it's a matter of contract rather than statute, its size and terms are negotiated between you and the contractor, not set by any government schedule.

What to Include When Negotiating One

1. A defined trigger point — usually substantial completion or a final walkthrough — for when the deficiency list gets created.
2. A written deficiency list attached to, or referenced by, the agreement, so there's no dispute later about what was actually outstanding.
3. A specific, reasonable timeline for the contractor to complete the listed fixes.
4. A clear release mechanism — what happens to the held funds once the fixes are confirmed, and what happens if they aren't done within the agreed time.
5. Language confirming the two holdbacks are separate — that this clause is in addition to, not instead of, any statutory holdback obligations under the Construction Act.

Common Mistakes Homeowners Make

• Assuming the statutory 10% holdback already protects them personally against deficiencies, when its real purpose lies elsewhere in the supply chain
• Waiting until after the contract is signed — or after the work is finished — to try to negotiate a deficiency holdback, once there's little leverage left to secure one
• Setting a vague amount or unclear release conditions, which can create a fresh dispute of their own once the work is done

Why This Belongs in the Contract, Not After

Leverage in a construction dispute comes largely from unpaid money. Once a contractor has been paid in full, your ability to compel them to come back and finish deficiency repairs drops sharply — you're left pursuing a claim rather than simply releasing funds you're already holding. Negotiating a deficiency holdback clause before you sign, while the contractor still wants the job, is far more effective than trying to introduce one partway through.

Frequently asked questions