Vapor retarder – Also called a moisture barrier or vapor barrier, these polyethylene sheets are laid over your crawl space floor and walls. This 10 to 20-mil thick impermeable barrier will prevent moisture from seeping through the dirt floor and porous concrete walls inside your crawl space.
1. Vapor Barriers. Moisture and vapor barriers provide thick plastic encapsulation for your crawl space. Use them to keep the moisture out of your home, eliminate water damage, block radon gas, and make the space less attractive to pests.
Is It OK to seal off my crawl space from the elements? The short answer is yes. But you don't fix the crawl space moisture problem and create a crawl space odor or soil gas problem. Like most things in life, a balance is better than one extreme or the other.
If you live in a particularly wet area, you should cover the entire sub-area all the way up to the foundation; however, if you live in a drier climate, it is wise to keep the plastic about 6 inches away from the foundation so the earth can breathe. The floor of your home does require a small amount of moisture.
Cover the dirt floor with a vapor barrier to isolate the house from the earth. Encapsulated crawl spaces with foam board-insulated walls make homes healthier, more comfortable, and easier to heat and cool.
While thinner plastic or regrind may be okay for short-term use, only reinforced virgin poly should be used for long-term applications like crawl space vapor barriers. Properly installed virgin reinforced poly should last 20 years or more in a crawl space.
A 20-mil vapor barrier would be the best choice no matter how you choose to use the space. This liner offers a mix of value and a certain degree of durability. A barrier this thick can endure rough handling during an inspection and hold up well in crawl spaces with significant traffic.
When considering DIY vs. professional crawl space encapsulation, cost is one factor. Materials such as vapor barriers and tape are inexpensive. You can expect to spend $1,000 to $4,000 to do your own crawl space encapsulation.
If your house is required to have flood vents, it's not a good idea to encapsulate. If you do, you're asking for trouble. Flood vents don't drain the crawl space from the bottom, like a bathtub. They drain from the side, where the foundation vents are located.
Today, crawl space science looks a lot different. To protect your crawl space, a closed or “encapsulated” crawl space is now preferred to an open, or vented crawl space. Encapsulated crawl spaces are consistently better at controlling moisture that enters from the damp earth or from warm humid air.
Crawl space insulation is a cost-effective way to reduce energy loss and make your home more comfortable. Spray foam insulation will provide your home with better thermal resistance and improved air quality.
Con: Potential HVAC Upgrade
After your crawlspace has been encapsulated, air movement through your home will be more restricted. This may mean that your HVAC system—designed with the former air circulation in mind—may no longer be as efficient as it once was.
In fact, some of the most effective upgrades for increasing home value have to do with improving comfort, durability, and energy efficiency. Crawl space encapsulation is one of them! Learn more about the benefits of crawl space encapsulation and how this important upgrade can affect the value of your home.
Encapsulation is different from vapor barriers because it seals out water vapor entirely and stops the process of moving water vapor from the ground up. Since the entire crawl space is encapsulated, including walls, your risk of moisture problems from water vapor decreases to almost zero.
A: The plastic cover or vapor barrier is definitely needed, especially in a dirt-floor crawl space. Without a vapor barrier, moisture will migrate to the surface of the soil and eventually cause serious problems in the crawl space, including mold and possibly structural rot. The plastic should cover the entire floor.
It sure does. Encapsulation can help with those foundation leaks, but not thermal transfer. That means you'd still be stuck with cold floors and uncomfortable rooms if you don't also create an air seal. Spray foam insulation is the best insulation option for the crawl space because it creates that air seal.
Where an encapsulated crawl space is sealed off completely, a conditioned crawl space only seals the floor, walls, and joists. Also, an encapsulated crawl space uses white plastic while a conditioned crawl space uses black plastic. Many people feel that an encapsulated crawl space is more visually pleasing.
Generally speaking, most companies will offer a warranty of between 15 and 20 years for a typical crawlspace encapsulation project. However, if the humidity levels are controlled and no catastrophic events such as flooding occur, a properly encapsulated crawlspace can last for more than 20 years.
What is Crawl Space Encapsulation? This process seals off your crawl space with white plastic, including the vents. A dehumidifier and sump pump are used to keep the space clean and dry. This ensures moisture doesn't have a chance to accumulate, eliminating the potential for mold and mildew problems.
You may need to encapsulate your home's crawl space to prevent these problems. Crawl space encapsulation costs an average of $5,500 but can range from $1,500–$15,000, depending on the work required. Our guide breaks down each price factor and answers other essential questions about the process.
While fans are a helpful tool in reducing moisture if your crawl space is already wet, sandbags are a great way to assist with waterproofing your home. Keeping sandbags in your crawl space close to your draining system is a preventative measure that will absorb any moisture that may come.
Black Plastic Sheeting is suitable for construction and DIY projects. It is made of recycled polyethylene to ensure long-term use. This sheeting can be used as a temporary cover for equipment and supplies. You can also create a vapor barrier or cover crawl spaces thanks to its multipurpose design.
Although 6 mil is the minimum standard, the crawl space environment may require a thicker material to effectively block moisture and gases. Not every plastic sheeting that is 6 to 20 mils thick behaves as a vapor barrier.