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3 Key Moves To Make When It Comes To Your Crawlspace Vents

Something you probably never hear about, right? Crawlspace vents are such a small component of your house so nobody would blame you if they were continuously on the bottom of the long list of important things you must pay attention to. But oftentimes the things that have the most value or quality are small. Take a car for an example. That car is like your house and the oil is like your crawlspace vents. When the oil is changed at the appointed time and there’s a constant flow of lubrication, the car runs smoother and safer. Ignore the oil in the car and things will start to go downhill fast and ultimately the car will sustain damage. In this article we will cover the best 3 things you can do with your crawlspace vents; but remember that car analogy because we will be using it again when we get to the number one best thing you can do on this list.

First, we must cover the basics, a quick synopsis of why crawlspace vents are important and the main function they provide for your home. Crawlspace vents are there to refresh the underside of your home. Open vents allow air to naturally circulate through and opens the hypothetical lungs of the home, making it breath. Statistically, the air from your crawlspace makes up 50% of the overall amount of air that circulates through your home. This means that your crawlspace vents can affect the health of both your home and whoever is inside. The air around us affects our health, bad air entering through your crawlspace vents or lack thereof can make someone more susceptible to illness and colds.

Closed vents block the air from outside from circulating through your home and would presumably keep you from the bad air from outside. But that is also assuming that the air inside your crawlspace is perfectly healthy, which it may not be. Crawlspaces hold a certain amount of moisture within them, and that moisture only has one way to go, up into your home. I don’t need to tell you that moisture invites things liked mold, pests, and humidity into your home because that is what most homes experience in the Carolina’s. But enough rambling on, let’s get to the stuff that matters, the 3 best things you can do with your crawlspace vents.

Number 1: Don’t open them

That’s right, although it has its advantages, keeping your crawlspace vents open can be a bad thing. Air circulation is the main benefit of having your vents open, it allows your house to breath. But the Carolina’s are well known for their hot and humid summers coupled with very mild winters. In a regular climate, the hot/humid summer air will add moisture to the crawlspace but before anything bad can result, the season changes to winter. Cold, aggressive winters help crawlspaces dry out from the hot/humid summer the season before. As for the Carolina’s, our mild winters aren’t cold enough to dry out our crawlspaces from the previous summer. This results in the crawlspace continuously gathering moisture year-round which in turn will cause higher energy bills, bad air quality, and mold/mildew to form.

Opening your crawlspace vents seems like the normal thing to do as seasons change but there are a couple factors that influence how this space is affected, such as:

HVAC/Duct Work – You may be in an area that isn’t surrounded by a lot of trees or foliage and therefore the chances of you getting adequate airflow into your crawlspace year-round is high. However, a common issue even these homes face is with their HVAC system. This system circumnavigates your home to pump A/C during the summer and heat during the winter. But it is bulky and cumbersome. If air is trying to circulate through your home and it hits resistance from the outer workings of your HVAC system, that air cannot flow properly. This results in only sections of the crawlspace being affected and leaves you with a problem.

No air flow – Living in the Carolina’s there is a high chance that where you live is surrounded by a ton of trees and foliage. These things block the flow of air from ever reaching your crawlspace vents and allows the weather of the various seasons to negatively affect the environment in your home.

Given this information, you would be inclined to close your crawlspace vents, right? Or install a fan attachment? Let’s move onto number two and find out.

Number 2: Don’t close them or buy a fan attachment

Crawlspace vents have their disadvantages regardless of if they are open or closed. When they are closed, air cannot get into the crawlspace and therefore there is no circulation to keep the relative humidity down. Given that crawlspaces have moisture entering from the ground that it sits on, that moisture will be unaffected when vents remain closed. The other option is to grab a fan attachment for all the crawlspace vents and have them installed to generate air flow without opening them. This option is worse for the health of your home. Fan attachments bring in air from the outside of the home, which will result in even more hot/humid air in the crawlspace.

Considering the Carolina’s usual climate throughout the year, the presence of moisture is practically guaranteed. Adequate airflow isn’t enough to sustain a suitable living environment throughout the year. Moisture control must work in tandem with adequate air flow for things to reach and remain at optimal living levels. That leaves us with the third and best optionfor what to do with your crawlspace vents.

Number 3: Seal your vents and encapsulate your crawlspace

Remember when I said that we were going to circle back on that car analogy earlier? Well, here it is. Your house is the car, and the oil is your crawlspace vents. Like before, if you ignore the oil, the entire car is affected. You must monitor your oil and change it when it needs to be changed. However, sealing your crawlspace vents and encapsulating your crawlspace is like having a completely new piece added to the engine that constantly circulates new oil throughout the car and it never has to be changed, resulting in the car always running at 100%.

There is a crawlspace vent debate throughout the waterproofing industry that argues whether its best to open or close your crawlspace vents. The answer is neither.Crawlspace vents must be professionally sealed, blocking any air from entering. Encapsulation of the entire crawlspace will then handle any kind of moisture you may have. Part of the full encapsulation process is the installation of a dehumidifier. A dehumidifier continuouslygrabs the air and expels clean, fresh air thatregulates humidity levels within your home and makes it a safe and healthy living space.

Carolina Basement Solutions is a waterproofing company that has been serving the Carolina’s for the last 5 years, and although young, we bring unmatched experience and expertise that is ideal for all waterproofing needs. Our mission is to provide the best customer experience in the industry and keep the Carolina’s dry, one waterproofing job at a time. When you need your crawlspace vents sealed and encapsulated, or any other waterproofing services, please give us a call at (833) 641-0517 or visit to schedule a FREE consultation today.

What Our Customers Are Saying

Great job, Professional, Well done. Pushed up a sagging load bearing wall from below that was ill constructed originally. Floor is rock solid now. Roger W. Whitmire, SC
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