Winter’s a-comin’ or heck, maybe it’s already here – Have you ever heard advice from your Grandpappy to seal up the vents under your home during winter to keep it warmer? Maybe you think this is starting to sound like a sensible idea considering the frozen and busted pipes you experienced last year . . .
At Anchor Foundation Repair, we’ve worked in Central Texas crawl space foundations all year round since 1985. We know what’s advisable for winter in this area based on our experience and research, along with a dash of common sense.
In this article, we answer whether it’s advisable to close up crawl space vents to keep your home and pipes warmer in the winter. Then, we’ll review recommendations of what you *CAN* do to keep your crawl space nice and toasty this season.
Should I Seal the Vents Under My Home for Winter?
The short answer to the “Should I close up my crawl space vents,” question is NO. Despite your Grandpappy’s good intentions, there are several reasons this is not a good idea. We don’t recommend it ever.
I’m sure you want a bit more reasoning, so here’s a longer explanation. Sealing up the crawl space takes away one of the primary forms of natural ventilation – cross ventilation. Closing off vents essentially impedes the natural flow of fresh air that can potentially circulate in the area under and within your home.
On top of that, there’s something called the “stack effect”. The stack effect is another of the natural ventilation processes of buildings and it happens from bottom to top. Air moves from the base of a structure, travels through the middle, and eventually escapes out the top of the attic.
So you remove cross ventilation by sealing off the vents, but the stack effect is still, well . . . in effect. This results in an increase in stale, stagnant air in your living space. The stack effect using sealed-off, non-circulated air can also bring in any mold or excess humidity from a damp crawl space. You might even notice this a little already when it rains and you start to smell some mustiness.
Even worse, dangerous radon gas buildup can also enter your living space when it has nowhere else to go. Radioactive radon gas inhalation is the second leading cause of lung cancer and the #1 cause of lung cancer in non-smokers, according to the EPA. Radon is colorless and odorless, so you don’t know if you’re breathing it in.
What we’re trying to say here is that you may create other more serious issues by closing off your crawl space vents, so why risk it?
Can I Safely Close Up Under Home Vents to Protect From Cold?
Will your Granddad’s spirit haunt you if you don’t close up those crawl space vents? Well, if you insist on sealing up the vents out of family obligation or tradition, there is a safer way to do it. You have to install a mechanical vent fan.
The EPA recommends that you have one vent remain open with a mechanical fan that can move 1 cfm of air for every 50 square feet of crawl space.
However, in my opinion, the benefits don’t outweigh the risks in our Texas climate. Keeping crawl space vents covered in the winter may raise the temperature a couple of degrees higher under your home, but it’s not going to be an impactful difference due to our mild winters. Plus, it sounds like a lot of trouble for the few days a year when it’s really cold.
Will Sealing Crawl Space Vents Prevent Frozen Pipes?
Even if you did safely seal off your crawl space vents, it’s not going to be a perfectly temperature-controlled environment. You might get a few degrees of difference. If it gets cold enough for long enough outside to freeze and bust your pipes, there’s a chance your pipes will freeze anyway. Plus, there are other remedies for preventing frozen pipes – see below!
What’s a Better Way to Keep Warmer in My Crawl Space Home?
There are other ways to keep the cold at bay and maintain a warmer temperature and feeling in your home. Here’s a quick rundown of some easy and inexpensive ways to protect your crawl space home and pipes from freezing temps.
- Put a few warming lights in the crawl space near exposed water supply lines during the short periods of freezing weather that we get.
- Wrap any exposed pipes with insulating foam sleeves or other appropriate material.
- Do a heavy drip on your faucets and any water fixture lines during the cold snaps.
- Put down some nice, warm area rugs on your hard floor surfaces. Heck, you can even put down area rugs over a carpet.
- Do like your Grandpappy would do and get you some house slippers!
You can choose to do one, two, or every single one of these suggestions fairly easily. These ideas are a lot simpler than doing the legwork for sealing up vents and getting a mechanical ventilation fan set up and properly installed. Plus, then you have to worry about un-sealing the vents later on.
Crawl Space Ventilation Is Important All Year Round
Now that you understand what’s at stake with the prospect of sealing up crawl space vents, hopefully, you’re also getting the idea that proper ventilation is really important. Promoting good ventilation under a crawl space home is crucial for your home’s general condition, your health, and even the health of your foundation.
At Anchor Foundation Repair, we don’t fix things that don’t need fixin’, we don’t try to sell you stuff you don’t need, and we don’t tell you to do stuff that you don’t need to do either. After 40+ years in business, that’s what’s best for our Brazos Valley community and for exceptional homeowners like you.
We’re here to help guide you through your home foundation decisions and empower you with needed information.
Now that you’ve got ventilation on your mind, check out The 6 Best Ways to Improve Ventilation Under Your Pier and Beam Home next.
