Replacement windows · Montreal
Replacing windows in Montreal, in the right order
In most Montreal boroughs, even a same-size replacement needs a permit, and the permit comes before the contract and the materials. If your plex qualifies for a subsidy, approval comes before the work. Get the order wrong and you can lose the subsidy or end up with windows the borough won't accept. We connect you with an independent local window contractor who can prepare the soumission your permit file asks for.
- Borough permit before the contract
- Frames your borough accepts
- RénoPlex and Rénoclimat in the right order
First, a check
Before replacing: would a new thermos or new hardware do?
A window that fogs, lets in drafts or won't close isn't always finished. Replacement is the right call for some windows and an expensive detour for others. The windows overview sorts common problems by symptom.
Fog between the panes
If the frame is sound, a new thermos clears it and the window stays.
A crank, latch or balance that fails
Worn hardware is replaced part by part; see crank and hardware repair.
Soft frames, rot, several failures at once
This is where replacement earns its place. Our repair or replace guide walks through the decision.
Two methods
Full-frame replacement or an insert from inside
A full-frame replacement (remplacement complet) takes the window out down to the rough opening, frame and all. The installer can then inspect and repair the opening, insulate around the new frame and correct water problems at the sill. It suits rotten frames and openings that leak.
An insert installed from inside (remplacement par l'intérieur) sets a new window into the existing frame. Finishes are disturbed less, but the old frame stays and the glass area shrinks slightly. It suits sound frames. Either way, shimming, insulating and sealing the new frame decide how well it performs.
Borough first
The borough permit comes before the contract
For a same-size replacement, the City says the rules differ by borough. Most boroughs require a permit even for identical windows; Saint-Laurent and Anjou generally don't, with exceptions. Sliding patio doors, bay windows and any new or enlarged opening need a permit throughout the City of Montréal. Check with your borough first, then follow these steps.
Check your borough's rules
Start with your borough's page or our borough permit guide. Some publish lists of accepted models; others set materials or opening types in heritage sectors.
Get a detailed soumission
The permit file needs a quote with taxes included and the manufacturer's technical sheet for the windows proposed; the pro we connect you with can prepare both. If the contract is signed at your home, Quebec treats it as itinerant commerce: it must be on paper and in French, and you have a ten-day right to cancel.
The documents the borough asks for
Colour photos with each window numbered and your certificate of location. In a condo, add a letter from each co-owner or a syndicate resolution.
Wait for the permit
Le Sud-Ouest strongly recommends having the permit before signing a contract, and Villeray–Saint-Michel–Parc-Extension asks owners to wait for it before buying materials. The same caution makes sense everywhere.
Install, then keep the paperwork
Keep the permit, contract and product sheets together for a subsidy claim or a future sale.
Frame materials
PVC, hybrid, aluminum or wood: what your borough accepts
Frame material isn't only a question of taste here. Some boroughs decide it for you.
PVC
Common, low-maintenance and widely accepted, but not everywhere: Le Sud-Ouest does not allow PVC exterior finishes on windows, frames included. See vinyl and hybrid windows.
Hybrid
PVC inside with an aluminum exterior. A Quebec renovation guide calls it the best compromise for this climate, and it is accepted where exterior PVC isn't, Le Sud-Ouest included.
Aluminum and wood
Required on some heritage buildings: in Le Sud-Ouest, buildings listed as témoins architecturaux need wood or aluminum. Wood also suits boroughs where keeping the original look matters.
Style counts too
In the significant sectors of Côte-des-Neiges–Notre-Dame-de-Grâce, sliding windows are not permitted. Guillotine and casement windows are the usual choices in older plexes.
Subsidies
RénoPlex and Rénoclimat: the order of steps matters
Two programs can help with a complete window replacement, and both are strict about sequence.
- RénoPlex, the City of Montréal's program, pays a set amount per window, door and patio door replaced on eligible buildings of two to five dwellings under a property-value threshold. Approval must come before work starts, and starting early can cost you the subsidy. See the RénoPlex program page.
- Rénoclimat, Québec's program, helps with ENERGY STAR certified windows and doors installed in existing openings, with an energy evaluation before and after the work. Replacing only the glass or the sash doesn't qualify. See Rénoclimat on Québec.ca.
In practice: borough permit, program approval, then contract and work. Check the program pages for current rules; our subsidy guide explains eligibility in plain terms.
What affects the quote
What determines the cost of replacing windows
No two soumissions are alike, because no two openings are. These are the factors a pro weighs:
- Full-frame replacement or an insert from inside
- Frame material: PVC, hybrid, aluminum or wood
- Style, size and any shape or divided-light pattern your borough requires
- Glass options such as low-E coatings or triple glazing
- Floor, access and the state of the opening, including sills and brick
- The permit fee, and how many windows are done together
Quebec quotes add GST and QST, and the permit file asks for the amount with taxes included.
ENERGY STAR
ENERGY STAR: one national standard
Canada's ENERGY STAR specification for windows now uses a single national performance level with no regional categories, so a certified window meets the same bar wherever it goes. Rénoclimat requires certification, and some boroughs refer to it in their rules. The NRCan technical specification has the details, and the product sheet in your permit file shows whether a model is certified.
Basements and bedrooms
Basements and bedrooms: egress windows
A bedroom window, including one in a basement, has to open wide enough to serve as a way out in a fire. Changing its size or style can bring the building code's egress rules into play, and an insert set inside an old frame can shrink the opening too much.
Anjou, which generally doesn't require a permit for same-size replacement, makes an exception when an existing bedroom or exit window doesn't comply. Ask the pro to check egress before choosing an insert for any bedroom.
Questions
Window replacement questions
Explore your options
Before you replace, compare
Local window contractors handle replacements across the island and nearby, including Le Sud-Ouest, Villeray, Westmount, Saint-Laurent and Verdun.
Tell us your borough and how many windows
Add the floor and a photo of the façade. We pass your request to an independent local window contractor who can prepare the soumission your permit file needs and walk you through the order of steps.