Installing a central air conditioning system in a duplex in Montréal: a strategic choice for comfort and property value
In Montréal’s urban context—where summers can be sweltering and winters long—central air conditioning has become an increasingly popular solution for improving residents’ comfort while boosting a property's resale value. When dealing with a duplex, however, the technical, legal, and practical considerations multiply. At AirGreen, we've guided many duplex owners in Montréal, Laval, Longueuil, the North Shore and the South Shore through the installation of high-performance HVAC systems. Here's a complete guide to everything you should know before getting started.
1. Understanding the needs of both units
Before any installation, it’s essential to determine whether the central air conditioner will serve one or both units of the duplex. This decision affects not only the required equipment capacity but also the legal and financial implications:
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If the system is shared by both units, a cost-sharing agreement for energy bills must be planned.
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If the system is meant for only one unit, it might be better to install an independent system, or even a wall-mounted or multi-zone system, depending on the layout.
At AirGreen, we always conduct an on-site evaluation to assess total square footage, number of floors, insulation quality, and sun exposure.
2. Choosing the right type of central unit
A central air conditioner for a duplex must be efficient, quiet, and compatible with the existing structure. Our experts generally recommend forced air systems with concealed ductwork to ensure even cooling throughout the home. Some of the most reliable brands we install include:
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Goodman (R-32)
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Lennox
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Bosch BOVA or BIVA
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Trane or Arcoaire
All these models are fully compliant with Québec's energy standards and can be combined with a central heat pump for both cooling and heating.
3. Inspecting existing ductwork (or installing new ducts)
Some duplexes in Montréal may already have ductwork from old oil or gas systems. However, these ducts must be inspected—and often replaced—to meet today’s efficiency and hygiene standards.
AirGreen provides full services for cleaning, adjusting, or replacing ductwork, offering spiral galvanized or insulated flexible duct options to minimize thermal losses.
4. Complying with municipal and co-ownership regulations
In Montréal, installing a central air conditioner in a duplex often requires a permit, especially if the outdoor unit is visible from the street or installed on a flat roof. In divided or undivided co-ownerships, written approval from other owners is required.
Our team handles all the administrative procedures, including submitting plans to the city, to ensure a 100% compliant installation.
5. Maximizing eligibility for LogisVert grants and other incentives
Good news: there are several grants available for installing an energy-efficient central air conditioning system, especially when paired with a heat pump.
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Hydro-Québec’s LogisVert Program: up to $5,000 in financial assistance depending on the equipment chosen.
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Rénoclimat or Chauffez Vert programs for converting to electric systems.
We help you prepare and submit all grant applications, recommending equipment that qualifies for maximum assistance.
6. Managing noise and the outdoor unit placement
Installing the outdoor unit on a duplex requires careful planning, including:
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Choosing the right spot: backyard, balcony, rooftop, etc.
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Reducing noise: some neighborhoods limit noise levels to 55 dB.
The models we install—like the Bosch BIVA R-454B or the Goodman GSZC R-32—are among the quietest on the market, ideal for densely populated residential areas in Montréal.
7. Planning for maintenance and system longevity
A properly installed central air conditioner should last at least 15 to 20 years with minimal maintenance. At AirGreen, we offer:
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Annual maintenance contracts
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Smart follow-up with maintenance alert systems
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Labor and parts warranty for up to 12 years, depending on the model
Additionally, we install systems with Wi-Fi connectivity, allowing you to control comfort remotely.
8. Hiring a certified RBQ and TEQ installer
One of the biggest mistakes is hiring an uncertified contractor. This can disqualify you from grants, compromise safety, and lead to costly issues later on.
AirGreen holds all necessary certifications (RBQ, TEQ, EPA) and we have extensive experience installing central air conditioners in duplexes and triplexes throughout Greater Montréal.
Real testimony from a homeowner in Montréal
We recently helped Ms. Morin in Rosemont install a 36,000 BTU Goodman R-32 central system to serve both units of her duplex. She had been struggling with uneven comfort and high electricity bills. After a comprehensive thermal study, we recommended a solution with independent zoning, which allowed her to achieve:
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A 27% reduction in her electricity bill
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Even cooling in every room of the home
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$4,800 in LogisVert grants
Why choose AirGreen?
Because we don’t just do installations. We support our clients from the first call to the final system adjustment, with personalized services, full cost transparency, and in-depth knowledge of Montréal’s HVAC realities.