What Are HRVs and ERVs—and Why Do Glenview & Northbrook Homes Need Them?
Modern homes in Glenview and Northbrook are built tight. New construction, energy-efficient windows, spray foam insulation, and weatherization upgrades all reduce air leakage—which is great for your energy bills, but creates a new problem: stale indoor air.
Without adequate ventilation, moisture, odors, VOCs (volatile organic compounds from furniture, paint, and cleaning products), and CO₂ build up inside your home. The result? Stuffy rooms, condensation on windows, and poor indoor air quality that can aggravate allergies and respiratory conditions.
A Heat Recovery Ventilator (HRV) or Energy Recovery Ventilator (ERV) solves this by continuously exchanging stale indoor air with fresh outdoor air—while recovering 70–85% of the energy from the outgoing air. You get fresh air without throwing away the heating or cooling you’ve already paid for.
HRV vs. ERV: What’s the Difference?
| Feature | HRV (Heat Recovery Ventilator) | ERV (Energy Recovery Ventilator) |
|---|---|---|
| Recovers | Heat only | Heat AND moisture |
| Best climate | Cold, dry winters (like Chicago) | Hot, humid summers AND cold winters |
| Winter benefit | Pre-warms incoming cold air | Pre-warms + adds moisture to incoming air |
| Summer benefit | Minimal | Pre-cools + dehumidifies incoming air |
| Humidity control | Reduces indoor humidity (exhausts moist air) | Balances humidity (transfers moisture both ways) |
| Best for | Homes with excess moisture (lots of cooking, showers, occupants) | Homes that get too dry in winter or too humid in summer |
Which Should You Choose in the Chicago Area?
For most homes in Glenview and Northbrook, an ERV is the better choice. Chicago’s climate has both very cold, dry winters and warm, humid summers. An ERV handles both seasons:
- Winter: Transfers some moisture from exhaust air to incoming air, preventing the painfully dry indoor air that makes skin crack and wood furniture shrink.
- Summer: Transfers some moisture from incoming air to exhaust air, reducing the humidity load on your AC.
An HRV may be preferred if your home has persistent moisture problems—excessive condensation on windows, damp basement, or a large household generating lots of shower/cooking moisture that needs to be exhausted.
How an HRV/ERV Works
Both HRV and ERV units contain a heat exchange core where incoming and outgoing air streams pass very close to each other without mixing. Here’s the process:
- Stale, warm air is drawn from bathrooms, kitchens, and utility rooms through dedicated ductwork.
- Fresh outdoor air is drawn in through a separate intake.
- Both air streams pass through the heat exchanger core, where 70–85% of the heat (and moisture, in an ERV) transfers from the outgoing stream to the incoming stream.
- The pre-conditioned fresh air is distributed to living areas and bedrooms.
- The stale air is exhausted outside.
The two air streams never mix—only energy transfers between them. This means you get fresh air without the contaminants you’re trying to remove.
Installation Costs for HRV and ERV Systems
| System Type | Equipment Cost | Installation Cost | Total Installed |
|---|---|---|---|
| ERV (whole-house, ducted) | $1,000–$2,500 | $1,500–$3,500 | $2,500–$6,000 |
| HRV (whole-house, ducted) | $800–$2,200 | $1,500–$3,500 | $2,300–$5,700 |
| Single-room ERV/HRV | $300–$800 | $200–$500 | $500–$1,300 |
| ERV integrated with existing HVAC | $1,200–$2,800 | $1,000–$2,500 | $2,200–$5,300 |
Whole-house systems include dedicated ductwork (if not using existing HVAC ducts), exterior wall penetrations, and controls. Financing available through Sunbit and PowerPay.
Benefits of HRV/ERV Installation
Better Indoor Air Quality
Continuous mechanical ventilation replaces stale air with filtered fresh air. This is particularly important for:
- Allergy and asthma sufferers (reduces indoor pollutant concentration)
- Homes with gas appliances (ensures adequate combustion air and reduces CO risk)
- Newly built or renovated homes (off-gassing from new materials)
- Homes with attached garages (prevents fume migration into living spaces)
Moisture Control
Excess indoor moisture in winter leads to condensation on windows, mold growth in walls, and structural damage. An HRV actively exhausts moist air, while an ERV balances moisture levels. Either option is far more effective than just running your bathroom exhaust fan.
Energy Savings
Without an HRV/ERV, the only way to get fresh air is to open windows—which wastes all the energy you spent heating or cooling your home. An HRV/ERV recovers 70–85% of that energy, meaning you get fresh air for a fraction of the energy cost of opening windows.
Code Compliance
The 2021 Illinois Energy Code (based on IECC 2021) requires mechanical ventilation in new construction that meets certain air-tightness standards. If your home was recently built or is being renovated to a high-efficiency standard, an HRV or ERV may be required to meet code.
Installation Options
Dedicated Duct System
The gold standard. Separate supply and exhaust ducts connect the HRV/ERV to individual rooms. Supply goes to bedrooms and living areas; exhaust comes from bathrooms, kitchen, and laundry. This provides the most balanced, effective ventilation.
Integrated with Existing HVAC
The HRV/ERV connects to your existing ductwork system, using the furnace blower to distribute fresh air. This is less expensive to install but requires the HVAC fan to run whenever ventilation is needed, which uses more energy.
Single-Room Units
Wall-mounted units that serve individual rooms. Good for targeted ventilation in a problem area (like a damp basement or stuffy bedroom) without the cost of a whole-house system.
Frequently Asked Questions
How much maintenance does an HRV/ERV require?
Minimal. Clean or replace the air filters every 3–6 months (similar to your furnace filter). Clean the heat exchange core once a year. Inspect the outdoor intake/exhaust hoods seasonally to ensure they’re not blocked by debris, snow, or ice. We include HRV/ERV maintenance in our annual maintenance plans.
Will an HRV/ERV make my house drafty?
No. The unit is balanced so that the same amount of air coming in equals the amount going out. There’s no pressure imbalance. The incoming air is pre-heated in winter (to within 10–15°F of room temperature), so you won’t feel cold drafts from the supply vents.
Can I install an HRV/ERV in an older home?
Absolutely. While older homes have more natural air leakage than new construction, an HRV/ERV still provides benefits—especially if you’ve added insulation, new windows, or weatherization. The unit can be installed in a basement, utility room, or attic with ductwork routed to key rooms.
How loud are HRV/ERV units?
Modern units operate at 25–40 decibels at the unit itself—about the volume of a quiet library. With the unit in a basement or utility room and insulated ductwork, you won’t hear it in your living spaces.
Do HRV/ERVs work in extreme cold?
Yes, but units rated for cold climates are essential in the Chicago area. Look for units with a defrost cycle that prevents the heat exchange core from freezing in sub-zero temperatures. All units we install are rated for our climate.
Schedule Your HRV/ERV Consultation
Whether your home feels stuffy, your windows fog up every winter, or you’re building a new energy-efficient home that needs mechanical ventilation, MMDS can design and install the right HRV or ERV system. We serve homeowners in Glenview, Northbrook, Evanston, and throughout the Greater Chicago suburbs.
Call (847) 221-6280 or request a free estimate online. Breathe easier without wasting energy—that’s what HRV and ERV systems deliver.