HPERV balcony ducting can conceal the outdoor air connections of an indoor all-in-one heat pump ERV beneath a balcony, keeping the balcony floor free of a conventional outdoor condenser. The installation works when the balcony soffit—the finished underside of the balcony—provides suitable space for separate air paths, weather protection and maintenance access.
EXINDA manufactures ceiling-ducted all-in-one heat pump ERV systems for apartment and multifamily project evaluation in Canada and North America. For developers, mechanical consultants and contractors, the opportunity is to coordinate heating, cooling, fresh air and energy recovery with the architecture. This guide focuses on the balcony duct route and its installation details.
What does the balcony installation concept involve?
The HPERV unit stays indoors, typically above a coordinated ceiling area. Indoor ducts distribute conditioned air to the apartment. Separate connections link the equipment to outdoor intake and discharge openings, with suitable external duct sections concealed beneath the balcony.
The balcony is therefore a potential route for outdoor air connections, not the location of the HPERV cabinet. A finished soffit hides the ducts while leaving the designed terminals open to outdoor air. The soffit cavity itself must not be treated as a shared intake or exhaust plenum.
The cover combines an EXINDA product image with a building reference to illustrate this concept. It does not identify the building as an EXINDA installation or confirm the function of its photographed ducts.
Why consider HPERV balcony ducting for apartments?
A balcony can provide a useful architectural zone for air connections when developers want to preserve usable outdoor space and limit visible equipment. Repeated apartment layouts also create an opportunity to repeat a coordinated duct, terminal and access detail.
This approach is most practical when the building team plans it before fixing the balcony soffit, ceiling heights and envelope penetrations. For existing buildings, the available route and permission to alter the exterior will determine feasibility.
- Preserve balcony space: keep a conventional apartment-level condenser off the balcony floor.
- Coordinate the façade: integrate external air terminals into a deliberate architectural detail.
- Support individual apartment operation: combine room conditioning and ventilation in an apartment-level system.
- Repeat a workable installation: use the same reviewed arrangement across matching apartment types.
Separate indoor airflow from outdoor duct performance
For the applicable EXINDA HPERV configuration, the indoor air side can deliver 300 CFM of cooling supply airflow at an external static pressure of 105 Pa, approximately 0.42 in. w.g. This provides a defined indoor duct-design point. Confirm the corresponding configuration and fan setting in the project submittal.
The 300 CFM figure describes indoor conditioned-air delivery. It is not the outdoor fresh-air rate, the heat-pump outdoor-side airflow, or a measurement of cooling capacity. Likewise, the indoor 105 Pa rating is not a pressure allowance for the balcony intake and discharge ducts.
| Air path | Design basis | Practical action |
|---|---|---|
| Indoor air distribution | Required room airflow and available indoor external static pressure | Calculate the governing supply/return path, branches, grilles and external accessories; balance room airflow. |
| Outdoor intake and discharge | Required airflow and fan performance for each corresponding outdoor air path | Include the balcony ducts, bends, transitions, dampers where applicable and terminal pressure losses. |
| Heating and cooling duty | Apartment loads and model performance at design conditions | Check capacity separately from airflow; account for the selected operating mode and cold-weather sequence. |
Allocate pressure loss across the complete path rather than assigning the full available pressure to the straight duct alone. Avoid squeezing a duct to fit a shallow soffit without recalculating resistance. Where a different duct shape is needed, size it by airflow and pressure loss rather than appearance.
How should the balcony air terminals be arranged?
Plan the intake and discharge as distinct air paths, positioned so discharged air can move away without being drawn back into the equipment or neighbouring apartments.
Review the balcony in section and elevation. A layout that appears separated on plan may still direct discharge toward the intake on the floor above. Include nearby doors, operable windows, adjacent terminals, prevailing exposure and the effect of the balcony enclosure.
Select terminals using their airflow and pressure-drop data, weather resistance and service requirements. A visually small grille is useful only if its free area and resistance suit the required airflow. Keep kitchen grease exhaust and dryer exhaust separate from HPERV air paths; a common architectural cover must not create a common mixed-air chamber.
How does the design support quiet operation?
EXINDA HPERV uses a patented structural design developed for quiet operation. The installation should preserve that product advantage through appropriate equipment support, vibration isolation and duct connections.
Position the unit and service opening thoughtfully relative to bedrooms. Avoid rigid connections that transmit vibration into the structure, and select indoor grilles and outdoor terminals to control air velocity and regenerated noise. If acoustic accessories are used, include their resistance in the duct calculation.
Commissioning should check the occupied rooms and neighbouring exposure points in the relevant operating modes. This confirms the acoustic result of the complete installation rather than relying on the cabinet design alone.
What changes for winter installation in Quebec?
The applicable EXINDA HPERV configuration includes additional freeze protection for low outdoor ambient conditions. Coordinate this equipment protection with the exposed ductwork, air terminals and condensate route.
For Montreal and other Quebec projects, review the selected model's operating range and heating output against the project's design temperature. Freeze protection protects equipment; available heating capacity determines whether it can cover the apartment load and whether supplementary heating is needed.
- Specify insulation and vapour sealing for duct sections exposed to temperature differences.
- Design condensate drainage and any exposed sections for the actual freezing exposure.
- Keep terminals accessible for inspection and clear of foreseeable snow or ice obstruction.
- Coordinate defrost operation, ventilation behaviour and any supplementary heating with the controls design.
Balcony shelter can reduce direct weather exposure, but the terminal location still needs a winter review. Do not rely on shelter alone as the freeze-protection strategy.
Keep maintenance simple after the soffit is finished
EXINDA HPERV is designed for straightforward maintenance. Preserve access to filters, internal service areas and drainage components through a correctly positioned indoor access opening. Allow the component removal clearances shown in the applicable service information.
For the balcony route, provide practical access to terminals and any components requiring inspection. Concealment should not require demolition of permanent finishes for routine service. Check this before closing the soffit, along with duct supports, joint sealing and envelope penetrations.
Choose the system for project fit, not a lowest-price promise
HPERV is a specialised solution for buildings with particular space, appearance and integration requirements. It should not be specified on the assumption that its purchase price is lower than a split system.
Compare complete installed arrangements: equipment, indoor and outdoor ducts, terminals, ceiling coordination, drainage, controls and future access. The value can lie in preserving balcony space and achieving an integrated apartment HVAC layout, even where the equipment price is higher. The project estimate should establish the actual cost difference.
Frequently asked questions
Can the HPERV cabinet be installed outdoors under the balcony?
The concept described here uses an indoor ceiling-ducted HPERV cabinet. Only the appropriate outdoor duct sections and terminals use the balcony soffit route. Outdoor cabinet installation requires a product specifically approved for that exposure.
Does 105 Pa mean any balcony duct length will work?
No. The stated 105 Pa at 300 CFM applies to the indoor air side of the applicable configuration. Balcony intake and discharge routes require their own airflow and pressure-loss review. There is no universal maximum duct length without the duct size, fittings and terminal data.
Can existing balcony exhaust ducts be reused?
Only after their original purpose, dimensions, condition and separation have been established. Existing kitchen or dryer exhaust ducts should not be repurposed as HPERV air paths without a complete redesign. A photograph alone cannot establish compatibility.
Does freeze protection prove the unit can heat every Quebec apartment?
No. Protection and heating duty are different checks. Select the unit using its heating performance at the project's winter design conditions and coordinate supplementary heat where required.
Request an HPERV balcony ducting review
Send EXINDA a typical apartment plan and balcony section, project location, heating and cooling loads, required ventilation airflow, proposed duct route and electrical supply. Our team can review the equipment fit and identify the model information needed for your design.
Explore the EXINDA AURA ceiling-ducted heat pump ERV. For the wider system-selection background, read our apartment HVAC guide without a separate outdoor condenser.
Discuss your apartment installation with EXINDA: info@exindagroup.com.
