A Solution for Fresh and Make-Up Air Happiness
Most of us are happy inside our homes, when the air we breath is fresh, and without the nastiness that can make us sick, or that is just plain stinky. As soon as it’s not fresh, we try to get rid of it. Some of us open a window or two. Others crank up an exhaust fan, in the kitchen or bathroom.
When it’s below freezing, or hot enough to melt pavement outside, either one of those strategies is cut short, or not used at all, because it makes us uncomfortable, which makes us unhappy. So, when we’re both comfy AND breathing fresh air, we tend to get really really happy, and happy people are good for the world. Sounds like an opportunity!!
Whether it’s because our home is tighter than tight, or there’s a need to neutralize the negative pressure in the home caused by turning on the range hood exhaust fan, bringing in outside air shouldn’t be done casually. By casually, I mean having a outside air inlet installed in the a floor or ceiling connected directly to conditioned space, where it can rush in on our heads or feet. I have it on good authority a)From everyone I talk to that that’s not happiness! You might disagree, but you also might be crazy.
So, the “opportunity” we have is to provide fresh and make-up air systems that not only do their job of bringing in outside air, but also keep us comfortable, healthy and, above all…HAPPY!!!
A Few Common Solutions
Many believe that an ERV b)Energy or Enthalpy Recovery Ventilator or HRV c)Heat Recovery Ventilator is absolutely the only way to bring fresh air in to a house. I say, in some cases, it’s a very good strategy. It depends! We have installed the ERV strategy before, and I’ve recommended it on dozens of homes, in the U.S. and abroad. We have proof that it works very well. The biggest “opportunity” (we don’t use the word “problem”, thanks to Dick Pritts, our mentor extraordinaire) with these systems, though, is justifying their cost when a very low cost system could be just as effective. For example, the ERV below was installed in this 2,811 square foot home, for just over $10,000, back in 2012.
Many also feel that bringing the make-up air in to the house as close to the range hood as possible is the best strategy. I agree that it is a very effective strategy. Plus, when you have ingenious ways of doing this, like our good friend Matt Risinger demonstrates it here, we’re loving it:
Did you notice that he said, “we don’t like these make up air dampers, because the bring air directly from the outside, in (where the happy people are), but we really need a way for that air to come in”.
Here’s a follow up video showing how it looks and operates, after install:
This may or may not work for you, but it certainly is one of the better solutions out there.
A Fresh Solution to Happiness
Here’s the strategy we like to use, no matter where the house is in the world, but it’s not necessarily appropriate for every home, and we wouldn’t think of recommending it as a one-size-fits-all strategy. d)Please consult with professional with a special focus in building science and/or home performance
Here’s the gist of it: We use a semi-conditioned space, like an attic or basement area, to act as a large “buffer zone” for the incoming outside air. After the air enters one of these spaces through a filtered in-line fan (for fresh air) or filtered damper (for make-up air), it dissipates, and is “pre-conditioned” by the semi-conditioned air in the space, then it enters the home.
This pre-conditioned outside air then enters the conditioned space in one of two ways.
- Through a transfer grille in a wall between semi-conditioned and conditioned space, that is strategically placed as close as possible the return grille of the air handler or furnace, where it is pulled in through the return grille, filtered again, conditioned properly, and distributed throughout the house via the ductwork.
- When the air handler / furnace is in the semi-conditioned space, and the local jurisdiction allows that space to act as the plenum, like we did in the High Performance Bungalow, the incoming outside air can be picked up directly by the air handler / furnace in the semi-conditioned space to be filtered again, conditioned properly, and distributed throughout the house via the ductwork.
When I said it’s not for every home, I mean that homes with spaces like semi-conditioned attics and/or basements are the ideal candidates for this strategy. Rooms that are never or rarely occupied, but a part of conditioned space, like a laundry room, can also work well.
The details of each system / strategy can vary, but the goal is to create a “buffer” between the incoming air and the happy people inside, to keep them alive (fresh air) and happy (comfortable)
There are many many many many other considerations that someone who knows and specializes in Building Science and Home Performance best practices needs to review and help with. DO NOT TRY THIS ON YOUR OWN, without consulting with someone. Depending on the location, there may be high levels of humidity to manage, or the opposite, very dry air. Often times it’s both! So, get help!
FYI: Typical System Specs
Footnotes [ + ]
|a.||↑||From everyone I talk to|
|b.||↑||Energy or Enthalpy Recovery Ventilator|
|c.||↑||Heat Recovery Ventilator|
|d.||↑||Please consult with professional with a special focus in building science and/or home performance|