Construction contracts in Québec: what the Civil Code says and the clauses to put in writing

Fixed or estimated price, extras, progress payments, holdbacks, acceptance, warranties, RBQ licence and itinerant contracts: the Civil Code, and what to write.

In Québec, most construction contracts do not need to be in writing to be valid: legally, a handshake is enough. That is exactly the problem. The day the client disputes an extra, holds back a payment or cancels midway, the signed text — or its absence — decides. And in three specific situations, writing is mandatory, with prescribed content.

This guide follows the Civil Code article by article, then sets out what to put in writing so that it works for you rather than against you.

Before signing: the duty to inform

A contract of enterprise is the undertaking to carry out a work for a client who agrees to pay a price (art. 2098). Before concluding it, the contractor must give the client “all useful information” on the nature of the work, the property and the time required (art. 2102). A detailed estimate — scope, materials, schedule — is the best way to show that you did.

The price: fixed or estimated, and the question of extras

The Civil Code distinguishes two ways of setting the price, and they do not protect the same party at all:

• Fixed price (art. 2109). The client pays the agreed price, with no reduction if the work cost less, and the contractor cannot ask for more if it cost more. Above all, the fixed price stays the same even when the initially planned conditions of performance were changed, unless the parties agreed otherwise.
• Estimated price (art. 2107). The contractor must justify any increase, and the client only pays it if it results from work or expenses the contractor could not foresee when the contract was made.

For extras, Québec law requires no particular form: what is needed is an agreement, not a form. But it is the contractor who will have to prove that agreement. An extra performed on a verbal agreement, under a fixed-price contract, is an extra whose payment depends on the client’s memory. The Office de la protection du consommateur even advises clients to have the contract state that the contractor must obtain their authorization before any unplanned work. Put it in yourself, with the procedure: a change order described, priced and signed before performing it.

Progress payments, payment and holdbacks

• Progress payments are not automatic (art. 2122). During the work, the contractor may require progress payments for the value of the work done and of the materials, if the agreement provides for it — and must first give the client a statement of the amounts paid to subcontractors and suppliers, and of those still owed.
• Without a clause, the price is due on acceptance (art. 2111). The client may then hold back an amount sufficient for the reservations made about apparent defects or poor workmanship, until they are corrected.
• The holdback for declared claims (art. 2123). The client may hold back enough to pay the workers and those who declared their contract to them, until the contractor gives a receipt for those claims. It is the other side of the legal hypothec: see Getting paid in Québec.

In these last two cases, sufficient security provided by the contractor removes the client’s right to hold back.

Acceptance of the work

At the end of the work, the client must accept it once it is performed and fit for its intended use; acceptance is the act by which the client declares they accept it, with or without reservations (art. 2110). It triggers payment and the warranties: set out in the contract how it happens — a walkthrough, a signed list of reservations, a date.

The contractor’s warranties

• One year against poor workmanship (art. 2120) — existing at acceptance or discovered within the following year.
• Five years for loss of the work (art. 2118) — caused by a defect in design, construction, performance or the ground, from the end of the work, solidarily with the professionals and subcontractors involved.

Article 2119 lets you escape liability by proving that the defect comes from a decision imposed by the client — choice of ground, materials, subcontractors or methods. You still have to prove it: when a client imposes a material against your advice, write it in the contract or in a signed amendment.

If the client cancels

The client may cancel unilaterally, even during the work (art. 2125); the contractor may only do so for a serious reason, and never at an inopportune time (art. 2126). The client must then pay, in proportion to the agreed price, the costs and expenses, the value of the work done and that of the property supplied that they can use; the contractor returns any advances received in excess (art. 2129). A contract that details the stages and their value makes that calculation far less contentious.

The RBQ licence number on every document

A licence holder must show their RBQ licence number in all advertising and on their estimates, bids, contracts and statements of account (Building Act, s. 57.1). Leaving it out is a penal offence (s. 194). Since February 12, 2026, members of the CMEQ and the CMMTQ, as well as contractors domiciled outside Québec, are exempt by regulation.

Signed at the client’s home: the itinerant-merchant rules

The Consumer Protection Act covers a merchant who solicits a consumer or concludes a contract away from their own address (s. 55). A contract signed at the client’s home, at the client’s express request, is not one — provided it was not solicited elsewhere (s. 57). But the regulation brings two cases back under the itinerant regime:

• the sale, installation or repair of a door, window, thermal insulation, roofing or exterior cladding — even if the client asked for the visit (regulation, s. 7);
• a visit requested by the client after a first contact made by the contractor, by phone or otherwise (s. 7.1).

Above $100, the itinerant contract must then follow a strict regime:

• A written contract with the particulars of section 58 — including the OPC permit number (separate from the RBQ licence), the description of goods and services, the price of each, taxes, the total, payment terms, performance dates — with the statement of cancellation rights and the form prescribed by regulation.
• Ten days to cancel, from the time each party has a copy (s. 59). The period becomes one year if a particular is missing, if the merchant has no permit, or if the work starts more than 30 days after the planned date.
• No payment before the period ends (s. 60) and, since November 7, 2024, no work either, installation included (s. 60.1).

New residential construction: the GCR guarantee contract

A contractor building covered new residential buildings — single-family homes, duplex to quintuplex, condominiums with up to four superimposed private portions — must join the guarantee plan. For the preliminary contract or the contract of enterprise, the contractor chooses the model; but there is only one authorized guarantee contract, GCR’s, approved by the RBQ, and it is signed at the same time. When a developer or builder sells a dwelling to a natural person who intends to live in it, the preliminary contract must include a ten-day right of withdrawal; the withdrawal indemnity cannot exceed 0.5% of the price (Civil Code, arts. 1785-1786).

The clauses to put in writing

• The parties: names, addresses, RBQ licence number (and OPC permit if the contract is itinerant).
• The description of the work, the attached plans and specifications, and what is excluded.
• The pricing method — fixed or estimated — spelled out.
• The extras procedure: a change order described, priced and signed before performance.
• The schedule, in working days, taking construction holidays into account.
• Progress payments, their stages, and the accompanying statement of amounts owed to subcontractors and suppliers.
• Acceptance: how, when, and the list of reservations.
• Choices imposed by the client against your advice, recorded.
• Cancellation: the value of each stage, so that the article 2129 calculation is simple.

The BatiCore team

We build BatiCore, management software for Québec construction contractors — estimates, job sites, CCQ payroll, compliance. Our articles cite dated public sources; when a fact comes from a regulator or a competitor, we say which one and when. Spotted an error? Write to us, we fix it.