Preventing Harmful Soil Gases: Essential Ventilation Tips

Are you sealing your crawl space correctly or unknowingly trapping harmful gases under your home? Join us as Michael Church from Crawl Space Ninja uncovers the essential steps to proper crawl space encapsulation and humidity control. You'll learn why simply sealing your vents and installing a dehumidifier might not be enough, especially if soil gases like methane, carbon dioxide, or radon are lurking beneath your home. Michael highlights the crucial role of proper ventilation, explaining how moving one CFM of air for every 50 square feet of crawl space can protect your living space from these dangerous gases.

Discover actionable solutions to common crawl space issues, including the installation of a Lomanco PCV1 fan to ensure effective ventilation while keeping your crawl space well-insulated. Michael also delves into the stack effect and radon mitigation, shedding light on how air movement impacts indoor air quality and why a submembrane radon mitigation system might be necessary for some homes. Tune in for a comprehensive guide packed with expert advice and practical tips to maintain a healthy and safe crawl space.

Video-Crawl Space Encapsulation with Ventilation
Crawl Space Ventilation Fans

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Transcript

Speaker 0: 0:00

Hey, michael Church, crawl Space Ninja. Today we're going to talk about is sealing all of the vents, the best option when you're encapsulating the crawl space and controlling humidity. Okay, so for those of you that don't know and if you're new to the channel you may not know because a lot of contractors don't know this is that encapsulating the crawl space, and what we mean by encapsulation is properly installing a vapor barrier on the ground up the walls overlapping, taping, mechanically attaching the ground up the walls, overlapping, taping, mechanically attaching and even insulating the walls in most cases, then installing a dehumidifier and sealing the vents. That is what we, as Crawl Space Ninja, deem as an encapsulation. So, that being said, if you have a home that you have soil gases you've got methane, you got carbon dioxide, you've got radon, you've got methane, you've got carbon dioxide, you've got radon you've got all these things percolating out of the earth and coming up into your crawl space If you completely seal that crawl space, vapor barrier does not stop those gases from coming up. It is a vapor barrier, not an air barrier. And then every time you cut the plastic or the fasteners come loose or the adhesive fails, then it just allows those vapors, including humidity and soil gases to enter the crawl space. So what's the solution According to the EPA now, in certain parts of the country they don't recognize this as far as code and in some parts of the country this is code where, according to the EPA, you should move one CFM of air for every 50 square feet of crawl space out of the crawl space.

Speaker 0: 1:38

Now we did a video. Where does that makeup air come from? I'll do a link down below so you can check that out. The point is is that if you totally seal that crawl space and don't give that soil gas somewhere to go, if that soil gas has any kind of odor or any kind of carbon dioxide or radon or anything else, it's going to enter your house. It's got nowhere to go, it's gonna go up. The stack effect causes it to go up. Remember, the stack effect, or the chimney effect, is that air enters the bottom of your home, your crawl space or your basement, and then exits the roof. That's typically how it moves A storm. If you've got a heavy wind blowing, it may affect it a little bit, but for the most part during all seasons the air goes in the bottom and moves up and out. So you don't want that air that is potentially harmful to you and your family to be coming up into your living space. So one CFM of air for every 50 square feet. Now if you've got a radon problem totally different situation. You should install what's called a submembrane radon mitigation system and I've done some radon videos if you want to look at those as well.

Speaker 0: 2:48

Talking about the health effects of radon, it's the number one cause of lung cancer among non-smokers, and not every part of the country is affected by radon, but many parts are.

Speaker 0: 2:58

So you want to make sure you're properly ventilating that crawl space.

Speaker 0: 3:02

So what we do is we take a Lamanco PCV1 fan it's about 110 CFM fan we put it in one of the foundation vents, seal all the others and then have the air blow out all the time, 24, seven, even in the winter, because the crawl space is sealed so well that the temperature isn't going to change with how we encapsulate and properly insulate the crawl space.

Speaker 0: 3:27

Now the Lamanco PCV1 fan does have a built-in switch where if it gets too cold in the crawl space it will shut off. I believe that's around 35 degrees, but none of our crawl spaces that we've encapsulated typically get below 60 degrees because most of the time you have your HVAC ducts that are also pumping heat in there while it's encapsulated. So make sure when you hire someone to encapsulate your crawl space they don't just seal all the vents and stick in a dehumidifier, that they seal all the vents but one have that ventilation happening and that way you can address those soil gases while also controlling humidity. I'm Michael Church Crawl Space Ninja. We hope you make it a happy and blessed day and we'll see you later.