Duplexes and triplexes
Plex balcony doors and windows: repair, replace, follow your borough's rules
In a Montreal duplex or triplex, each flat has its own way outside, and upstairs that's usually a glass balcony door (porte de balcon) with a transom above it, reached by an outside staircase. Those doors take sun, freezing rain and daily use, and sooner or later one sticks, drafts or loses its handle. Whether you own the building or rent a flat in it, the question is the same: can the original be repaired, or does it need replacing within your borough's rules? We connect you with an independent local pro who works on plex doors and windows to answer it.
- Original doors repaired where possible
- Transom and borough rules explained
- Owners and tenants on equal footing
The plex
The Montreal plex: a balcony door on every floor
In Villeray, the duplex and triplex became the standard house after the Second World War, with the spiral front staircases, back lanes and sheds that mark residential Montreal. Verdun's Moffat area filled with plexes earlier, in the 1920s. Each flat has a door at the front and one at the back, and on the upper floors those doors open onto balconies and galleries.
Most Montrealers rent, and most homes are flats like these rather than detached houses. That shapes door work: an owner with several balcony doors to deal with, tenants who need visits arranged, and a staircase that every door, pane and tool has to climb.
Repair first
Repairing the original balcony door
Older plex balcony doors are often wood, hinged, and fitted to an opening that has settled over the decades. A good deal can be fixed without replacing them.
Renting? Speak to the owner before anyone books a repair. The Tribunal administratif du logement explains how urgent and necessary repairs are handled, for tenants and owners alike.
Broken handle
A snapped or loose handle (poignée) is usually replaced on its own, or together with the lockset if the old one can't take a new handle.
Drafts and sticking
New weatherstrip, adjusted hinges and a trimmed edge can cure a door that rubs or lets the cold in.
Fogged or cracked glass
The thermos, or the single pane in an older door, is replaced while the door stays. See door glass.
Tired wood
Soft spots on the bottom rail can often be repaired and repainted. RénoPlex even includes an amount for restoring a wood door on eligible buildings.
A screen for summer
A screen door or retractable screen lets the balcony door stay open in July. See porch and balcony screens.
Replacing it
Replacing: transom, glass proportions and colour
When the door has to go, the borough may care as much as you do about what replaces it. Verdun spells it out more than most. Its rules for replacing doors require the transom (imposte) to be kept or restored, accept door glass in the original proportions or a few defined shapes, want that glass clear or finely textured, allow upper-floor balcony doors to have shorter glazing with a guillotine sash, and ask that all doors on a façade share one colour, entry doors excepted.
Those rules are Verdun's own. Other boroughs have their own versions, so check with yours before choosing a door; the installer you're matched with can build the quote around what it accepts.
Permits
Hinged door or patio door: the permit question
Swapping a hinged balcony door for a sliding patio door is a common wish, since a slider doesn't swing into a small room or onto a narrow balcony. It's also a change the City watches closely: a sliding patio door always needs a permit, and widening the opening to fit one is a second trigger. In heritage sectors, some boroughs require the original form to be kept on street-visible façades, which can rule a slider out at the front.
Replacing a hinged door with a similar hinged door still needs a permit in most boroughs. The patio door replacement page shows how the permit file comes together.
Access
Outside stairs and upper floors: planning access
Upper-floor balcony doors are reached by the outside staircase, often a spiral one, or through the flat. Doors, glass and tools all travel that way, so access is worth planning before the visit rather than on the day.
Tell the pro which floor each door is on and send a photo of the staircase. In winter, clear and salt the steps beforehand. If tenants live upstairs, agree on dates early; door work done before July 1, moving day, avoids sharing the stairs with trucks and boxes.
What affects the quote
What shapes a balcony door quote
Plex work is quoted door by door, and these make the difference:
- Repair or replacement, and how many doors are done in one visit
- Material: wood, PVC, aluminum or hybrid, within your borough's rules
- Transom, glass shape and colour requirements
- The glass itself: a single pane or a thermos, clear or finely textured
- The floor, and access by the outside staircase
Tell us the floor of each door and attach a photo of the façade.
Subsidies
RénoPlex for plex doors and windows
RénoPlex is aimed at this kind of building. For eligible buildings of two to five dwellings under its property-value threshold, it pays set amounts per replaced window, door, door with transom and patio door, and toward restoring a wood door. Approval must come before the work starts; starting early can forfeit the subsidy. It's a City of Montréal program and doesn't apply off-island.
A thermos replaced on its own isn't covered. Our subsidy guide explains eligibility and how RénoPlex sits alongside Rénoclimat.
Front windows
Façade windows: original form and type
The same logic applies to the windows beside the balcony doors. Whether the façade has guillotine (hung) or casement (battant) windows, boroughs with heritage sectors want replacements to respect the original form. The Plateau, for one, asks that a replacement keep the original characteristics, while repairing original windows generally needs no permit outside heritage protections. Le Sud-Ouest doesn't accept a PVC exterior finish on windows, though hybrids are allowed.
For the windows themselves, see window repair for cranks, latches and sashes, and replacement windows when the frame is done.
Questions
Plex balcony door questions
Explore your options
Related plex help
Independent pros work on plex doors and windows across the older boroughs, including Villeray, Verdun, Le Plateau-Mont-Royal, Rosemont–La Petite-Patrie and Le Sud-Ouest.
Tell us the floor of each door
Attach a photo of the façade and, if you can, the staircase. We pass your request to an independent pro who works on plex doors and windows, and we follow up so it keeps moving. All [door and screen services](/doors/) are listed in one place.