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What Is a Crawl Space Vapor Barrier? Do You Need One?

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Crawl spaces are prone to excess moisture, especially in North Carolina, where the climate is very humid. Moisture from the soil gets trapped in crawl spaces and adds to the already damp environment. Moisture does not serve any good purpose for your home or your belongings, like furniture and appliances.

Water vapor can slowly erode your home’s structure from the ground up, causing structural damage, pipe erosion and allergens. If there is moisture in your crawl space, you may notice signs like rusty pipes, mold, musty smells or mildew growth.

What Is a Vapor Barrier in a Crawl Space?

A crawl space moisture barrier is an impermeable material that covers the floor of your crawl space. Professionals install it on the ground and around the perimeter. Vapor barriers in crawl spaces help prevent moisture from the soil from entering the crawl space area.

The most common material for crawl space vapor barriers is polyethylene sheets. Polyethylene is a durable plastic that’s impermeable to water vapor. It must be six millimeters thick to block moisture and serve as a termite barrier. Vapor barriers less than six millimeters thick are flimsy and puncture easily. Since it’s plastic, vapor barriers are relatively inexpensive and easy to install.

The Benefits of Vapor Barriers

Preventing excess moisture in your crawl space offers many benefits, such as:

  • Preventing mold growth.
  • Keeping your home dry.
  • Preventing a musty smell.
  • Leading to lower energy bills.
  • Keeping pests away.
  • Preventing rusty pipes.
  • Allowing for easier repairs.
  • Helping prevent structural damage.
  • Preventing electrical problems, such as short circuits and blown fuses.
  • Keeping your HVAC system running smoothly.
  • Preventing dangerous gases from entering your home.
  • Helping prevent respiratory problems like allergies and asthma attacks.

Signs Your Crawl Space Needs a Vapor Barrier

Excessive humidity can cause a slew of problems, but certain signs can warn you of moisture. If you notice any of these, you may need a crawl space moisture barrier:

  • Your crawl space has insulation: Your crawl space may be insulated if its foundation lies on open vents, which can cause high humidity levels. However, insulation isn’t waterproof. Therefore, you still need a moisture barrier to prevent water vapor from seeping through the ground.
  • Your crawl space has metal pipes: Crawl spaces have plumbing systems, like bathrooms and kitchens. If you have metal pipes in yours, a vapor barrier can prevent rusting that might cause leaks.
  • You have electrical problems: If you notice electrical problems, like flickering lights, inside your home or crawl space, moisture may be shorting your circuits. Fixing leaky pipes and cracks and preventing excess moisture will solve this problem.
  • Your crawl space has a dirt floor: Any moisture in the soil can get into your crawl space. Installing a crawl space vapor barrier prevents this moisture from lingering underneath your house and causing damage.
  • Your home smells musty: Humidity buildup can cause your home to smell musty. Often, this is from moisture in your crawl space, which you want to fix as soon as possible.
  • Your crawl space is hard to clean: When dirt sticks to surfaces, cleaning your crawl space can be challenging. A vapor barrier prevents dirt from sticking by blocking moisture.
  • You want to prevent structural damage: Structural damage may occur if water seeps through and causes wood rot or mold. This damage requires immediate attention before it worsens and leads to significant repair costs.
  • You’re concerned about respiratory problems: Having too much humidity in places where people sleep may cause respiratory problems like allergies or asthma attacks. Installing an impenetrable surface in your crawl space will reduce humidity buildup and help prevent these problems.
  • You want to lower your energy bills: Installing a crawl space moisture barrier might lower your energy bills. Less moisture means less energy needed to run your HVAC system.

Should You Install a Vapor Barrier?

Most homes and buildings can benefit from a crawl space moisture barrier. Whether you notice signs of excess moisture or not, it’s essential to consult with a contractor who specializes in crawl spaces. They can inspect your crawl space to determine its condition and if a vapor barrier is necessary for you.

An inspection also helps them identify cracks, leaks or other damage that you need to repair before it worsens. Additionally, professionals only install vapor barriers after repairing cracks and leaks. You don’t want to install a vapor barrier to prevent excess moisture but have it not work because water has seeped through leaks and cracks.

Contact HydroHelp911 for Vapor Barrier Installation

When you want to repair or improve your crawl space, HydroHelp911 is the best in the business. We’ve provided clients with our expertise and high-quality services for over 10 years. As a company, we understand how important your home is, so we always ensure we communicate openly with you every step of the way.

We offer various crawl space, basement and foundation services, including vapor barrier installation. When you choose us, your local family-owned business, we put your satisfaction first. Contact us today to discuss your vapor barrier installation. We offer free consultations, affordable financing options and lifetime warranties.

Contact HydroHelp911 Today!

HydroHelp911 will do everything we can to ensure your experience with us is excellent.

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