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do not vent your crawl space

Is a Vented Crawl Space Bad for My DC Home?

Remedy the problem by sealing the vents and encapsulating the crawl space.

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do not vent your crawl space

A vented crawl space is increasingly becoming the subject of debate. People are now questioning whether venting is a good idea. Initially, contractors thought installing vents in the crawl space would aid cool the home much like a vented attic does. Building codes even made it mandatory for homeowners to vent their crawl space.

Studies now show that venting isn’t helpful. Not only does it open your home to moisture but it also encourages mold and pests and a host of other problems. In this post, we shall show you how venting can damage your crawl space and why encapsulation is the answer to your recurrent moisture issues.

Why Venting is Bad for the Home

The first reason venting isn’t good for your home is that it creates an opening for all the insects and pests you loathe. Spiders, termites, crickets, mice, and rats will enter the crawl space anytime and start breeding. When they come in, pests and insects won’t rest. They will destroy your wooden beams, defecate and dirty the crawl space, and even introduce fleas. Within a short time, your once clean and usable crawl space will turn into a mess. And to clean it up, you will have to get a professional who will charge you a considerable fee.

Your vented crawl space will raise humidity levels to uncontrollable levels. Moisture will encourage fungi and mold to grow. Both will contaminate this space. Some spores may enter the living space above and trigger allergies. You won’t be able to use or access the crawl space until a mold remediation company comes and cleans it. Again, this will cost you money. 

A vented crawl space also lets in toxic gas and dust particles from the outside. When these get into your home, they can cause lung disease and respiratory problems. And that means more hospital visits and cash spent on medication. You wouldn’t want kids to cough throughout the night and miss school because of dust-induced allergies, would you?

More than 50% of the indoor air originates from this below-ground space in your home. If the air is cold and damp, you can be sure it will come in and make your floors and walls cold. The same goes for the air you breathe indoors. As a result, you will find yourself turning on the heater for several hours just to create the perfect living conditions. Come the end of the month, you will find yourself with an unusually high energy bill.

Moisture and water are destructive in nature. For example, moisture causes wood joists to rot and below-the-home pipes and ducts to rust. Some of this water can also reach the foundation walls and cause them to crack. Left unchecked, it will weaken the underlying structure that supports the home above. Your home could crumble anytime. 

When your crawl space falls apart, you will have to hire a contractor to carry out crawl space repairs. This is an exercise that will cost you money that could run into thousands of dollars. But can you really put a price on health and happiness? If you don’t keep your crawl space sealed and healthy, it means this area of your home will continue deteriorating and your loved ones enduring cold, musty, and unbreathable air. 

Plastic encapsulation is the Way Out

Given that your vented crawl space will let in moisture and damage it, you have no recourse but to seal the vents and install a plastic vapor barrier. We recommend a 20-mm thick polyethylene barrier with antimicrobial properties that will stop water from entering the crawl space and at the same time prevent mold growth. The whole exercise will take some hours. If the crawl space is dirty or in a state of disrepair, it has to be cleaned and fixed first before encapsulation starts.

If you’d like to carry out crawl space repair or encapsulate the crawl space, talk to your trusted crawl space contractor in DC. We’re happy to supply you with a free crawl space estimate and advise on the next steps.

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