HRV vs. ERV: Which Ventilation System Does Your Ontario Home Need?
Written by the Northland Home Comfort team — TSSA-registered heating, cooling and hydronics contractor (FS-R-50021) serving Simcoe County and Muskoka. Updated October 2026.
Short answer: For most Ontario homes an HRV (heat recovery ventilator) is the right choice: it brings in fresh air, exhausts stale air, recovers most of the heat and dries the house out in winter, which is what tight homes here need. An ERV (energy recovery ventilator) also transfers moisture, which helps homes that get too dry in winter or that run air conditioning hard in a humid summer. Installed, either runs about $2,500 to $4,500 in a retrofit and is included in the mechanical package on a new build. Ontario’s building code requires mechanical ventilation in new homes.
Why a tight house needs ventilation
Homes built or renovated to current standards are sealed well enough that moisture from cooking, showers and breathing has nowhere to go. The signs are condensation on the windows in January, stale air, lingering odours and, over time, mould around window frames. Bathroom fans alone do not fix it. A balanced ventilator brings in as much outdoor air as it exhausts, through a core that recovers most of the heat.
HRV vs ERV
| HRV | ERV | |
|---|---|---|
| Transfers | Heat only | Heat and some moisture |
| Winter effect | Dries the house (good for most Ontario homes) | Keeps some indoor humidity (good if the house gets too dry) |
| Summer effect | Brings in humid air | Keeps some humidity outside, lightens the A/C load |
| Best for | Typical homes, cottages, anywhere condensation is the problem | Very tight new homes that run dry, homes with heavy A/C use, larger households in small spaces |
| Cost | $2,500 – $4,000 installed (retrofit) | $3,000 – $4,500 installed (retrofit) |
In Simcoe County and Muskoka, winter condensation is the complaint we hear most, and an HRV solves it. We recommend an ERV when a tight new home with few occupants is running under 25 percent humidity in January, or when summer humidity control is the priority.
What a proper installation looks like
- Sized to the house per the building code ventilation rate, not the biggest unit on the truck.
- Dedicated ducts where possible: exhaust from bathrooms, kitchen area and laundry; supply to bedrooms and living space. Dumping both into the furnace return is the cheap way and the worst-performing one.
- Balanced with a flow hood after installation so supply equals exhaust. Unbalanced units pressurize or depressurize the house.
- Controls the homeowner understands: a dehumidistat for winter, boost switches in bathrooms, and a schedule for low-speed continuous operation.
- Defrost strategy suited to -25°C, and condensate drained properly.
Running it
Run the ventilator on low continuously in winter and use the bathroom boost. Clean the filters every two to three months and the core once a year. If the windows still fog, turn it up; if the house feels too dry, turn it down or consider an ERV core. Pair it with a whole-home humidifier only if the house still runs dry with the ventilator turned down.
Where it fits in a new build
On custom homes we design the HRV or ERV into the mechanical package with the heating and cooling, with its own duct runs planned before framing. On radiant-heated homes with no furnace ducts, the ventilator gets a small dedicated system. See our indoor air quality page and custom home design checklist.
Frequently asked questions
New homes are required to have mechanical ventilation under the Ontario Building Code, and an HRV is the usual way to meet it. Older homes that have been air-sealed, re-insulated or had windows replaced often need one too; condensation on windows in winter is the sign.
HRVs suit most Canadian homes because winter air is dry and the HRV removes excess indoor moisture. ERVs are better where a very tight home runs too dry, or where summer humidity and air-conditioning load are the bigger issue.
About $2,500 to $4,000 for a retrofit with reasonable duct access; ERVs run $3,000 to $4,500. New-build installations with dedicated ducting are priced within the mechanical package.
Yes, on low speed continuously through the heating season, with boost from the bathrooms. Continuous low-speed operation uses little energy and keeps humidity and air quality steady.
It can, and it is the common shortcut, but dedicated exhaust and supply ducts perform much better. If it must share the furnace ducts, the furnace blower has to run whenever the HRV does.
Condensation on the windows or stale air in a tight house? Ask us about a properly sized, balanced HRV or ERV.
