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Why Is Venting the Crawl Space a Huge Mistake?

Venting your crawl space is a thing of the past. Nowadays, by keeping crawl space vents open, you can put your home and your family in danger.

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Crawl spaces have been a cause of headaches for many years. Although they are undoubtedly a part of many homes, they cannot be used for basically anything, so simply neglecting them was the valid option for most homeowners. According to building codes from the 1950s, around that time it became the best practice to ventilate these areas. Back then it was a popular option that the airflow they provided would reduce moisture. Since moisture is the number one cause of problems in crawl spaces, this sounded like a great idea. Unfortunately, it wasn’t. 

Fast forward 40 years and new research emerged showing that vents allowed for airflow, but that the conditioned air went right out the vents. Since then, crawl space ventilation has been on the decline, but nowadays homeowners are seriously questioning the usefulness of these fixtures. Not only is the work they do pointless, but it has been proven that venting can really harm the crawl space area. 

open crawl space vent problems

Problems with Crawl Space Vents 

Although venting can improve air circulation, it leaves your crawl space exposed to moisture and many other issues. If you decide to vent your crawl space, soon you may realize you have made a costly decision. 

During the humid summer days in Chattanooga, TN, with the air going in and out of your crawl space, a lot of moisture will end up in this part of your home. As days go by, the moisture will slowly build up and eventually cause damage. It can cause the wood to rot, encourage mold growth, ruin your fiberglass insulation and in the end, compromise the structural integrity of your house. 

Apart from letting moisture in, vents are convenient openings on your house for termites and other pests. Since a large part of your home was built from wood, termites are your biggest enemy. If they move into your crawl space, they will do what they do best—chew everything they run into, causing enormous damage to your wooden structures. Unfortunately, it is not that easy to notice that you have termites. Once you are aware of this threat, it is already too late, and your home is in serious trouble. Even worse, a lot of home insurance policies won’t cover the cost of repairs when the damage is caused by pests, since this type of situation could be averted with regular maintenance. 

Vents on your home will also let the rodents in. If there are harsh weather conditions outside, such as rain or snow, these furry pests will find shelter in your crawl space. As you may know, rats and mice breed incredibly fast, and in just a couple of months, your crawl space will be crawling with rodents. Not only will they gnaw and damage your wooden structures, but they will tear out the insulation and defecate everywhere. Not only will your home’s structure be in danger, but this space will become wildly unsanitary. After the mice have inhabited your crawl space and used it as their playground, you won’t be able to recognize it anymore. 

Another problem with vents is the toxic air. The air that will float in through the vents won’t always be fresh and clean. In fact, it could be toxic and put your family’s health in danger. Even healthy members might experience breathing problems, while those with respiratory conditions such as asthma will be in a far worse state. Letting the toxic air into your home through the crawl space could result in many doctor visits unless you do something about it. 

If your crawl space becomes humid, the other parts of your home will become affected as well. You may notice that the temperature in your home has dropped and that the air smells kind of musty. To resolve these issues, you might have to let your HVAC system run at all times, which will reflect in higher monthly bills. 

Should I Vent the Crawl Space? 

These are just some of the reasons venting the crawl space is not a good idea. Although people in the 1950s thought it was a good idea, building codes have come a long way since then, and today it is clear that vents are not your friends. Having a vent opening on your home can invite vermin and moisture into your house, which is always a recipe for a disaster. 

Looking from every possible angle, venting the crawl space is a bad idea. Once the rats, termites, mice, or moisture come into your crawl space, they can cause huge structural damage, thereby lowering the value of your home. Repairing the damage could cost a fortune since you might have to fix the insulation, wooden joists, and cracks on the walls. If you wish to sell your home, you will have to sell it for much less money than you hoped for. If, on the other hand, you want to continue living there, you might have to spend a lot of money on the repairs. Either way, it is a situation you don’t want to be in. 

One thing you cannot put a price on is your family’s health. If toxic air comes in through the vents, your loved ones will get sick, and you surely want to avoid this scenario. 

Therefore, if you have a home with a vented crawl space, call professional contractors in Chattanooga, TN, and let them seal it off with vent covers.  Afterward, they could encapsulate it to help keep the moisture out. This heavy-duty plastic vapor barrier will keep your crawl space clean and dry. However, this is not the only solution to the moisture problem. You should also consider investing in a dehumidifier that will keep the moisture levels under control

Schedule a free inspection with AFS Foundation & Waterproofing Specialists today and find out the best ways to protect your home and your family. 

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