Can I duct my Toronto home HRV fresh air supply to the bedrooms only and exhaust from the bathrooms?

Yes, you can design an HRV system to supply fresh air directly to bedrooms and exhaust from bathrooms, and this is actually an excellent approach for Toronto homes. This configuration provides fresh air where people sleep (where CO2 buildup is highest) and removes moisture and odors at the source.

This dedicated HRV ductwork approach is often superior to connecting the HRV to your main HVAC system because it operates independently of your furnace or air conditioning. When your HVAC system isn't running (common during Toronto's mild spring and fall weather), you still get continuous fresh air exchange and moisture removal.

For bedroom supply, you'll want to install small supply grilles (typically 4" or 6" round) in each bedroom, positioned away from the bed to avoid drafts. The HRV should deliver approximately 15-20 CFM per bedroom for adequate fresh air. In Toronto's climate, this fresh air helps dilute CO2 buildup overnight and reduces stuffiness that's common in tightly sealed modern homes or older homes with new windows.

For bathroom exhaust, connect the HRV to existing bathroom exhaust points or install new grilles. Each bathroom should exhaust 20-30 CFM continuously, with boost switches available for higher extraction during showers. This constant low-level exhaust prevents moisture buildup that leads to mold growth - a significant concern in Toronto's humid summers and during winter when bathroom moisture has nowhere to go in sealed homes.

The key advantage in Toronto's extreme climate is that the HRV's heat recovery core captures 70-85% of the heat from outgoing stale air and transfers it to incoming fresh air. During a -20°C Toronto winter, incoming outdoor air is preheated to approximately 15-18°C before entering your bedrooms, dramatically reducing the energy penalty of ventilation. In summer, the process reverses - hot humid outdoor air is pre-cooled and dehumidified by the outgoing air-conditioned exhaust air.

Installation considerations for GTA homes: The HRV unit itself (typically mounted in the basement or utility room) needs two connections to the exterior - one for fresh air intake and one for stale air exhaust. These should be positioned at least 6 feet apart and away from dryer vents, gas appliance vents, and high-traffic areas. The dedicated ductwork runs are usually smaller diameter (4-6 inch) than your main HVAC ducts, making them easier to route through finished spaces.

Ontario Building Code compliance: This configuration meets OBC ventilation requirements and may actually exceed minimum standards by providing continuous fresh air to sleeping areas. The system should be balanced so supply and exhaust CFM are equal, preventing pressure imbalances that could affect combustion appliances.

Professional installation is essential for proper sizing, balancing, and commissioning. The HRV must be sized based on your home's square footage and occupancy, ductwork must be designed for proper airflow distribution, and the system requires electrical connections and controls integration. Expect to invest $3,000-$5,000 for a quality HRV system with dedicated ductwork in a typical GTA home.

Find local HVAC and ductwork contractors experienced with HRV installations through the Toronto Construction Network directory at torontoconstructionnetwork.com/directory?trade=hvac.