Install the ventilation during the renovation, never afterward
A brick cottage in Ville Mont-Royal, built in 1948 and expanded for the first time in the 1980s. The owners were completely renovating the basement: stripping it back to the foundation, spray-foaming the rim joists and concrete wall, building new interior framing, and adding a bathroom.
They called us for an unusual reason, and that is what makes this project interesting: they called before, not after. The general contractor had told them something we hear far too rarely—“have someone come in for the ventilation before I close up the walls.”
This is the only right sequence. It changes pretty much everything.
What an open renovation makes possible, and a finished home prevents
On projects where we arrive after the drywall is installed, we spend half our time working around obstacles. On this one, we were able to:
- Choose straight duct runs, without unnecessary elbows and therefore without unnecessary pressure loss.
- Use rigid ductwork where a finished home would have forced us to use flex duct.
- Place the supply and exhaust grilles where they belong—not wherever access happened to remain.
- Run the wall-control low-voltage wiring through the studs, without visible molding or conduit.
- Properly insulate the exterior ducts along their entire length, with full access to the penetrations.
The labor cost of a ventilation HVAC installation in an open basement is significantly lower than that of the same installation in a finished home. Homeowners who postpone ventilation until “later” pay twice: once in additional work, and once in lost performance.
Why the Greentek PREMIER 2.0H
A series designed for high static pressure
The PREMIER range from Greentek is designed for applications with high static pressure. In construction terms, that means long duct runs, numerous elbows, and restricted sections—exactly what is found in older homes in Ville Mont-Royal, where finished ceilings, original beams, and successive additions impose constrained routes.
A unit that delivers its rated airflow only under ideal laboratory conditions is disappointing as soon as it is connected to a real duct network. That is the criterion that guided the choice here, more than the raw efficiency figure.
Performance data
- Type: HRV (heat recovery ventilator), with a cross-flow core.
- Airflow range: 60 to 200 cu. ft./min. at 0.4 in. w.g.
- Connections: 6-inch round ducts, side ports, with plastic collars and rubber gaskets.
- Sensible recovery efficiency : 75% at 0 °C.
- Power consumption: 52 W at low speed, 168 W at high speed. Fan efficiency of 1.3 cu. ft./min. per watt, maximum current 1.4 A at 120 V.
- Dimensions: 21 7/16 in. high × 23 7/8 in. wide × 11 11/16 in. deep, weighing 46 lb (21 kg).
- Filters: washable electrostatic filters.
- Certifications: cETL, HVI, and ENERGY STAR.
Two figures deserve an honest comment.
The 75% at 0 °C is lower than what cross-flow core units display, reaching 80–84%. The PREMIER's cross-flow core recovers less, but it creates less resistance, and the cabinet remains light and slim—11 11/16 inches deep, allowing it to fit inside a standard framed partition without encroaching on the room.
The second number is the depth, precisely. In a VMR basement where every inch of headroom matters, a unit less than 12 inches deep mounted against a partition rather than beneath the joists preserves headroom.
Defrosting: what we explain every time
The PREMIER uses supply-fan shutdown defrost, triggered when the outdoor temperature drops to -5 °C or below. During the cycle, the supply fan stops and the exhaust fan switches to high speed to defrost the core more quickly.
It is a simple, robust system with no additional moving parts. However, you need to understand the consequence: during these cycles, the house is temporarily depressurized, and this depressurization is more pronounced than during a simple fan shutdown because the exhaust airflow increases.
On this job, that was not an obstacle—the basement had just been waterproofed with urethane, there are no naturally vented combustion appliances in the house, and the heating is electric. In a house with an open wood-burning fireplace or a naturally vented boiler, we would have recommended a unit with recirculation defrost. This is the kind of check we perform before recommending a model, not after selling it.
Suspension against a framed partition
The unit is suspended by chains—the kit is supplied as standard with the PREMIER series—anchored in doubled-up studs, with vibration-isolating springs and flexible sleeves at the connections.
The critical point in a basement renovation: the unit is suspended before the partition is closed, but the required service clearance must be calculated based on the finished wall, not the current wall. We systematically add the thickness of the drywall and planned finish to the calculation; otherwise, the cabinet door hits a wall that did not exist on the day of installation.
The condensate drain runs to the floor drain with a primed trap and verified slope.
The exterior intakes and the Ville Mont-Royal regulations
This is the most underestimated local constraint on this project.
Ville Mont-Royal strictly regulates the appearance of façades, and adding elements visible from the street—caps, grilles, ducts—is not trivial. We positioned both caps on a side façade not visible from the public right-of-way, while complying with the usual technical requirements:
- At least six feet of spacing between the fresh-air intake and the stale-air exhaust, to prevent the unit from re-aspirating what it has just expelled.
- Distance from the dryer exhaust and from any combustion-appliance terminal.
- Sufficient height above the accumulated snow level, taking the actual snow-clearing conditions at the entrance into account.
- Rodent screens on both caps.
Before drilling, we check the applicable municipal regulations. On the island of Montreal, each borough and each related municipality has its own rules, and they genuinely differ from one area to another. A cap installed in the wrong location in a city like VMR may have to be redone at the contractor's expense.
Washable electrostatic filters
The PREMIER comes with washable electrostatic filters rather than disposable cartridges. Over the unit's service life, this represents real savings and makes maintenance simple: rinse with water and dry completely before reinstalling.
The key point: an electrostatic filter must be completely dry before being put back in place. A damp filter clogs faster and can contribute to odors in the ductwork. We demonstrate this to the customer once at the end of the work, with the filter in hand.
The EHC 2.5 wall control
The recommended control for the series is the EHC 2.5 multifunction controller, which operates the unit in three modes:
- Ventilation: exhausting stale air and replacing it with outdoor air.
- Recirculation: redistribution of indoor air from one area to another without bringing in outdoor air — useful during periods of smog or wildfires.
- Standby: the unit remains inactive as long as the indoor relative humidity stays below the setpoint.
Four speeds can be selected: low, medium, normal, or 20 minutes per hour. We set the humidity setpoint with the client, explaining the winter target of 30 to 40 %, rather than leaving the factory setting in place.
Five decisions to make before the contractor closes the walls
- The equipment location, taking the finished wall into account rather than the current wall.
- The ductwork route, favoring rigid ducts and straight runs while everything is open.
- The location of the grilles, chosen according to how the rooms are used, not according to what remains accessible.
- The routing of the low-voltage wiring for the wall control through the studs.
- The position of the exterior hoods, verified against municipal bylaws before the first hole is drilled.
These five decisions cost one technical visit. Revisiting them afterward costs hours of demolition.
Maintenance
Electrostatic filters should be rinsed every 3 to 6 months and dried completely, the core should be washed once a year, and exterior hoods should be inspected in the spring and fall. We provide the HVAC maintenance schedule in writing, along with the airflow measurements taken during commissioning.
Codes and financial assistance
For new construction and additions, balanced mechanical ventilation is governed by the Quebec Construction Code, and the Novoclimat program imposes its own thresholds. In a major basement renovation, adding insulation and air sealing changes how the entire home behaves — this is precisely when not having an air exchanger becomes a problem. For financial assistance, we verify eligibility on a case-by-case basis according to the programs active when the work is carried out.
Our service areas
AirGreen installs, replaces, and services air exchangers, heat pumps, wall-mounted air conditioners, and central systems in Ville Mont-Royal, Outremont, Saint-Laurent, Côte-des-Neiges, Ahuntsic, Westmount, and throughout the island of Montréal, as well as in Laval, Longueuil, on the North Shore, and on the South Shore.
If you're renovating a basement or an entire home, call us while the walls are still open. That's when ventilation costs the least and works best.