Retrofitting balanced ventilation into an existing home is usually blocked by duct access, not by the device itself. Vyana’s through-wall design sidesteps duct runs entirely, which makes it the rare HRV alternative that installs in an afternoon, not a weekend.
Window-mount: about 20 minutes with a screwdriver. Slots into single or double-hung windows.
Through-wall: 90 min to 2 hr. Cut the opening, set the sleeve, mount the unit.
Retrofit constraints in typical housing stock
Three things make traditional HRV/ERV retrofits expensive:
Duct access. A central HRV needs supply and return ductwork to every served room. In homes with finished basements, cathedral ceilings, or no attic access, running that ductwork means cutting drywall, usually multiple rooms.
Electrical. Most HRVs need a dedicated 120V circuit. If your panel is full or the nearest outlet is far from the unit location, add an electrician.
Envelope penetrations. Fresh-air intake and exhaust need outside access. Existing homes often lack a convenient exterior wall or roof penetration path.
Cumulative effect: a ducted HRV retrofit runs $5,000–$15,000 installed for a typical single-family home. That’s why most existing U.S. homes don’t have mechanical ventilation despite ASHRAE 62.2 recommending it.
Two install paths for Vyana
1. Window-mount. The fastest path. Vyana slots into a single or double-hung window opening, held by an adjustable frame that pinches the sash against the frame. Under 20 minutes with a screwdriver. No wall-cutting, no electrical rerouting. Best for renters or anyone who wants to avoid permanent modifications.
2. Through-wall. A permanent installation in an exterior wall. Cut a 10-inch hole, insert the sleeve, seal, and mount the unit. 1–2 hours with a reciprocating saw and standard tools. The resulting install is invisible from indoors and looks like a neat vent cap outside.
Vyana doesn’t require a separate ducted-return install path. The intake unit works near your existing HVAC return register, so the existing ductwork is the distribution. No new ducting.
Code considerations
ASHRAE 62.2 sets the residential whole-house ventilation rate. Most U.S. jurisdictions reference ASHRAE 62.2 directly through the IRC. For a 2,000 sq ft home with 4 occupants, you’re targeting around 50 CFM continuous plus boost capacity for bathrooms and kitchen.
Check with your AHJ (authority having jurisdiction) whether a through-wall ventilation retrofit requires a permit. In most jurisdictions it doesn’t, since balanced ventilation through-wall units fall under the same code category as a bathroom exhaust fan.
Pick the right model
Pick by home size and HVAC layout, not by room count.
- Solo Vyana: Up to 1,200 sq ft. Single-zone homes or apartments. Limited cross-ventilation, so best for small or open-plan spaces.
- Dual Vyana: 1,200–2,400 sq ft. The most common configuration. One intake near the HVAC return, one exhaust at the far end of the house. Full whole-house cross-ventilation.
- Triple Vyana: 2,400–4,000 sq ft. Scaled version of Dual for larger or multi-story homes.
- Custom Vyana: 4,000+, commercial, or unusual layouts. Contact-only sizing.
What to expect on install day
For a through-wall install:
- Pick the wall. Exterior-facing, ideally near the HVAC return for the intake unit and at the opposite end of the house for the exhaust.
- Check for studs, pipes, or wiring. Stud finder covers most. Infrared camera adds confidence.
- Cut the opening per the unit’s spec.
- Slide in the wall sleeve. Seal with the supplied gasket and construction adhesive.
- Mount the interior unit to the sleeve.
- Plug in. Self-test on first power-up.
- Pair with the app, set the schedule, walk away.
Most customers finish in 90 minutes to 2 hours per unit. If you own a drill, a reciprocating saw, and a level, you have the tooling.
Frequently asked questions
Do I need a permit to install Vyana?
In most U.S. jurisdictions, no. Through-wall ventilation retrofits typically fall under the same permit category as a bathroom exhaust fan, which is permit-exempt. A few jurisdictions require mechanical permits for any balanced ventilation device. Check with your local building department to be sure.
Can one Vyana handle a whole house?
For homes under 1,200 sq ft with an open layout: yes. For multi-zone homes with distinct bedrooms and living areas: no. Dual is the right answer because cross-ventilation depends on having an intake on one side and an exhaust on the other.
What’s the install time difference between window-mount and through-wall?
Window-mount: 15–20 minutes. Through-wall: 90 min to 2 hours for a confident DIYer; add an hour if it’s your first time with a reciprocating saw.
What about the climate I live in?
Vyana’s firmware adapts year-round. An installation in August handles December fine. Firmware updates over the air address any climate-driven optimizations. The intake unit pauses outdoor-air intake automatically during severe air quality events.