Do You Need an Architect in Quebec, or Can a Designer Handle It?

Quebec regulates the practice of architecture, and the Architects Act reserves certain acts to members of the OAQ. Under the Act, only an architect may prepare, modify, sign and seal plans, specifications, tender documents, work certificates, expert reports or supervision reports relating to the construction, expansion or modification of a building; supervise such work, including for a compliance certificate required by law; and give, sign and seal written opinions in the course of those activities. If your project's design falls within those reserved acts, an architect is not optional — the law requires one.

This is the part most explanations get backwards, so it belongs first and stated plainly: a building that does not fall into one of the specific exempt use categories below is subject to the Act regardless of its dimensions. Size does not exempt a building on its own. A small building outside the exempt categories still needs an architect. The exemptions are narrow, defined by use, and they are what you have to fit into — not a threshold you fall under.

The Act exempts a limited set of buildings. An architect is not required for:

Each rule combines a use category and dimensional limits, and a building has to satisfy both to be exempt. A commercial establishment of three storeys, or one over 300 m², is subject to the Act even though “commercial establishment” is on the list. And a use that isn't on the list at all — an assembly building, an institutional use, residential above four units — is subject regardless of size.

Much commercial work is renovation, not new construction, and there is a separate exemption for it. Works that modify an existing building fall outside the Act when they do not change the building's use and do not affect its structural integrity, its firewalls or fire separations, its exits and their access, or its exterior envelope.

That is a meaningful carve-out, and it covers a large share of interior fit-out work — reconfiguring a leased office or store, replacing finishes, moving non-structural partitions. But the conditions are cumulative: change the use, touch the structure, alter a fire separation, affect an exit or the path to it, or modify the envelope, and the exemption no longer applies. A fit-out that looks purely cosmetic can cross the line the moment it moves a rated wall or a required exit.

This is the most important part of the whole question, and the part most likely to cause a real problem. Where the Act applies, an architect must have direction of the design work. It is not enough to have someone else prepare the plans and bring an architect in at the end to review and seal them. The OAQ publishes guidance stating explicitly that this after-the-fact sealing arrangement is not compliant — the architect has to direct the design from the outset, not certify someone else's work at the finish.

The stakes are not trivial. On conviction, penalties under the Act reach $62,500 for an individual and $125,000 for a company — and those are on top of municipal sanctions, which can include a demolition order. So the risk of getting this wrong is not only a rejected permit; it can be a fine and, in the worst case, an order to take down work already built.

If you take one thing from this guide, take this: where a project is subject to the Act, engaging an architect to direct the design early is the compliant path, and the only one. Drawing first and shopping for a seal later is the arrangement the OAQ specifically warns against.

The law is one thing; where you actually encounter it is the municipal permit counter, and it's worth knowing how that works.

The safest and cheapest point to settle whether your project needs an architect is before design starts — not after a reviewer flags it, and certainly not after the work is built.

Because “designer,” “architect,” and “engineer” get used loosely, it's worth being precise, because the credentials are not interchangeable.

Interior designers. In Quebec, interior designers have no professional order and no reserved acts. The APDIQ (Association professionnelle des designers d'intérieur du Québec) is an association professionnelle — a membership body — not an ordre. Membership signals professional standing and standards; it does not confer any authority to perform an act reserved to architects. A designer, however qualified, cannot substitute for an architect where the Act requires one. That is simply how the professions are structured in Quebec, and any firm that offers design services — ours included — works within it.

Professional technologists. Technologues professionnels, members of the OTPQ, have a regulated scope that was expanded by regulation, and within that scope they can prepare and seal certain plans that would otherwise require an architect. This is a real and distinct pathway — but its scope is specific and technical, and we won't try to summarise it here, because getting the details slightly wrong would be worse than not stating them. If a technologue professionnel is relevant to your project, confirm the scope with the OTPQ.

Engineers. Structural questions are a different profession again. Structural work typically requires an engineer's seal, which is a separate question from whether an architect is required. A project can need both an architect (for the building design) and an engineer (for the structure); they are not alternatives to each other.

On a question this specific, the right move is to check your actual project against the authority's own tool, not a general guide. The OAQ publishes a decision aid — “Aide à la décision — Loi sur les architectes” — that walks you through whether a given project requires architect-prepared plans. Run yours through it. If anything is close to the line, ask the OAQ directly.

Here is the honest version, so you know how this affects working with us specifically. Interior fit-out work that does not change a building's use and does not affect its structural integrity, its fire separations, its exits and their access, or its exterior envelope sits outside the Architects Act. That work we carry end to end, under our own RBQ licence, with our design done in-house by APDIQ-member designers.

Where a project is subject to the Act — a building outside the exempt use categories, or work that changes use or touches structure, fire separations, exits, or the envelope — an OAQ-member architect directs that portion of the design from the outset. Not brought in at the end to seal; engaged early to lead, as the law requires.

That is the whole arrangement: we determine at the start which side of the line your project falls on, we carry the work we're permitted to carry, and we bring in an architect to direct where the Act requires it. The line isn't ours to move — this guide exists so you can see exactly where it is.