Changing Codes

In April of 2021 Oregon will adopt the 2021 Oregon Residential Specialty Code which will force the use of Heat Recovery Ventilators(HRVs). As a student of building science I can’t say I’m unhappy with this code change, however I understand the resistance from my industry counterparts. Years ago I started mandating the use of HRV’s in our projects after talking with Mark LaLiberte at a conference and he explained it in a very simple manner that I will use here. If you think of your house as a human body, you would not build a human without lungs right? So why would you build a house without lungs (HRV)? It makes perfect sense when you simplify it down to this level.

But what is an HRV really do? An HRV is a continuous ventilation system that removes all the bad, dirty air from a home and brings in fresh air from the outside.

Ok, but I don’t want cold air blowing on me! No, the heat recovery portion of the system takes the warmth out of the air it exhausts and puts it into the fresh air before it puts it back into the house so you don’t feel the cold outside air. As well, the HRV is a low-flow system that does not push air at a rate that you really feel, it just works in the end.

The diagram below illustrates how it works, there are also several ways to add these to HVAC systems so that they do not break the bank. It is an added cost, but as we have started to increase the tightness of our homes, we need to think of better ways to ventilate. There is also added benefits to controlling the air pressure, humidity, and temperature throughout a home that will be felt by the occupants.

Please consult a qualified HVAC installer with more detailed questions, but know that we are here to help as well.

Cheers,

Nathan D. Young