Energy Recovery Ventilators (ERVs)

Sealing up a home to make it more energy efficient is one of the best things you can do for your comfort and your utility bills, but it comes with a tradeoff. A tightly sealed house does not breathe on its own the way an older, leakier home does, and that means stale air, moisture, and indoor pollutants can build up with nowhere to go. An Energy Recovery Ventilator solves that problem by giving your home a controlled way to exchange stale indoor air for fresh outdoor air, without giving up the energy savings you worked to gain.

Responsible House installs ERVs for homeowners throughout Central Virginia as part of our broader approach to indoor air quality and building science. Benefits of a properly installed ERV include:

• Continuous fresh air without opening a window
• Lower humidity swings between seasons
• Reduced strain on your HVAC system
• Fewer indoor pollutants and allergens circulating through your home
• A home that stays efficient instead of stuffy

We are a certified building analyst professional with decades of general contracting experience behind us, so we do not just drop in a piece of equipment and leave. We evaluate how your entire home handles air, moisture, and temperature before recommending a ventilation strategy, which means the system we install is sized and set up correctly for your specific house.

How an Energy Recovery Ventilator Works 

An ERV is a mechanical device that continuously pulls stale air out of your home while bringing in an equal amount of fresh outdoor air. What makes it different from just cracking a window is what happens to that air on the way through the unit. As the outgoing and incoming air streams pass by each other inside the core of the ERV, they transfer both heat and humidity between them.

In the winter, warm air leaving your home passes its heat to the cold air coming in, so you are not paying to heat outdoor air from scratch every time your home ventilates. In the summer, the process runs in reverse. Humid outdoor air gives up much of its moisture to the drier air leaving your home before it ever reaches your living space, which keeps your indoor humidity in check and takes some of the load off your air conditioner. A well built ERV core typically recovers somewhere around 70 to 80 percent of the energy that would otherwise be lost, which is a meaningful difference on your monthly energy bill.

Why Fresh Air Matters in a Sealed Home

Homes built or upgraded to modern efficiency standards are airtight by design, and that is a good thing for your energy bills. The downside is that pollutants like cooking exhaust, cleaning products, off gassing from furniture and building materials, and everyday carbon dioxide from breathing do not have anywhere to escape on their own. Without a way to bring in fresh air, that stale air just keeps recirculating. An ERV gives your home a built-in, controlled exchange so you get the fresh air your family needs without undoing the sealing work that keeps your energy bills low.

ERV vs HRV: What Is the Difference?

Homeowners researching ventilation options often come across Heat Recovery Ventilators, or HRVs, and wonder how they differ from an ERV. Both systems work on the same basic principle of exchanging stale indoor air for fresh outdoor air while recovering energy in the process. The difference comes down to moisture. An HRV transfers heat between the two air streams but does not manage humidity, which makes it a better fit for very dry climates. An ERV transfers both heat and moisture, which makes it the better choice for a climate like ours in Central Virginia, where summer humidity is a real factor in indoor comfort and air quality.

Is an ERV Right for Your Home? 

Not every home needs the same ventilation solution, which is why we do not recommend an ERV as a one-size-fits-all fix. Homes that have been recently air sealed, insulated, or converted to a conditioned attic are usually good candidates, since that work naturally reduces how much a house breathes on its own. Homes dealing with lingering humidity problems, odors that will not go away, or family members with allergies or asthma also tend to see a real benefit from adding an ERV to the picture.

Energy Recovery Ventilators FAQ

Does an ERV increase my energy bill?

An ERV does use a small amount of electricity to run its fan, but the energy it recovers from the outgoing air stream far outweighs that cost in most homes. The net effect is usually a lower energy bill than running mechanical ventilation without any energy recovery at all.

How is an ERV different from my HVAC system?

Your HVAC system heats and cools the air that is already inside your home. An ERV brings in fresh outdoor air and removes stale indoor air, working alongside your HVAC system rather than replacing it. The two systems work together to keep your home comfortable and properly ventilated.

How often does an ERV need maintenance?

ERVs need periodic filter changes to keep the airflow clean and the core operating efficiently, similar to changing a furnace filter. We can walk you through a simple maintenance schedule during installation so your system keeps performing the way it should.

Will an ERV help with humidity in my home?

Yes. Because an ERV transfers moisture between the incoming and outgoing air streams, it helps prevent your home from becoming overly humid in the summer or overly dry in the winter, which is one of the main reasons it is a better fit than an HRV for our climate.

Call the ERV Experts in Central Virginia

Responsible House has been solving indoor air quality and energy efficiency problems for homeowners since 1995. We look at the whole house as a system instead of selling one-off equipment, so when we recommend an Energy Recovery Ventilator, it is because our diagnostic testing shows it is the right fit for your home, not because it is the easiest thing to sell. Our team handles everything from the initial evaluation through installation, and we stand behind the work.

Call 540-942-2061 or contact us to find out if an ERV is the right solution for your home.