Are you seeking a way to prevent moisture accumulation in your home or business? Save yourself the stress of rotted wood and lingering mold that is accompanied by moisture intrusion. Crawl space insulation, such as crawl space vapor barriers, can prevent these costly and consuming issues, while also leading to significant savings and protection.

What is a Crawl Space Vapor Barrier?

Crawl Space vapor barriers provide an insulated seal to lock moisture out of crawl spaces and prevent moisture from penetrating the air in the crawl space. By sealing the opening in crawl spaces, the accumulation of water through the crawl space and into the home is prevented, impeding moisture issues such as mold and rot from forming in the home.

Vapor Barrier Composition and Characteristics

The most commonly used vapor barrier is reinforced polyethylene plastic sheeting, or poly for short. Poly sheeting is preferred because it offers the dual benefit of durability and value, making it ideal for providing vapor barriers for many cases of water intrusion that are operating within a budget. On the other hand, reinforced ploy sheeting offers a variety of different thicknesses for a range of strengths that can match your project’s needs.
Teaming up with a trained contractor will help you determine which vapor barrier thickness is best for your project. 

vapor barrier

Crawl space vapor barriers are a minimum of 6 mil and a maximum of 20 mil in thickness, with the latter offering the most fortified and heavy duty protection. Each mil is the equivalent of 0.001 inches of thickness, with 6 mils of reinforced poly often being recommended for the standard crawl space insulation project.
Another term to be familiar with when it comes to vapor barriers is “perm.” The perm rate is used to represent the likelihood of water vapor passing through materials. The less permeable a material is, the lower the perm rating will be. To earn the official classification of “vapor barrier,” the material used must rate at 0.1 perms or below. To put this into perspective, 6 mils of poly sheeting clocks in at 0.06 perms, making it a suitable and trusted barrier material.
When it comes to determining how thick of poly sheeting to select, both the function of the crawl space (what is it being used for) and the material of the crawl space ground should be taken into consideration. Crawl spaces that are more susceptible to wear and tear, such as ones regularly accessed for maintenance purposes, will need to be thicker since there is a greater chance of puncture in the crawl space insulation.

Insulation Life Expectancy

You may be familiar with poly if you frequent hardware stores. The poly used in vapor barrier insulation is of the “virgin” variety, while the kind found in stores is often composed of recycled or “regrind” poly. Regrind poly may be suitable for short-term use, but the thinner plastic is often fraught with impurities that don’t make it a reliable long-term insulation solution. On the other hand, virgin poly should last for 20 years or more when it is professional installed in your crawl space. That means a singular insulation process can easily keep your crawl space protected for over two decades.

Brace and bolt

Does Your Building Need a Crawl Space Vapor Barrier?

When it comes to determining if your home needs a crawl space vapor barrier, there are several factors that could make your property in need of moisture insulation. Homes that reside atop exposed dirt crawl spaces are often in need of crawl space insulation since this situation makes it very easy for water to seep into the home.
Older homes are also more likely to require crawl space vapor barrier insulation because they tend to have small openings for ventilation built into the crawl spaces to facilitate easy access of air.

Unfortunately, these ventilations tend to be problematic, allowing moisture located beneath the home to remain trapped there. Lastly, climates that are particularly humid are also more susceptible to crawl space moisture intrusion.
If you have any of the aforementioned home characteristics that make your property susceptible to crawl space moisture intrusion, it’s a good idea to connect with a professional contractor to start discussing your crawl space insulation. Vigilant homeowners can also inspect their building for telltale signs of crawl space moisture. The following list will help you determine if excessive moisture is seeping into your crawl space.


Signs of Moisture Intrusion:

  • Pools of water after a heavy rain
  • Signs of rust, rot, mold, or mildew
  • Efflorescence (salt deposits) on the crawl space walls
  • Strong, musty odors
  • Difficulty breathing, headaches, allergies, asthma, and other related illnesses
  • Increased levels of radon
  • Pest and/or insect presence
  • Exterior home paint peeling

Why Install a Crawl Space Vapor Barrier?

Water intrusion and moisture-laden air promote a host of unsavory side effects in the home, including rot, bacteria, mold, fungus, and mildew. Crawl space vapor barriers are needed to seal water out of crawl spaces that are more susceptible to water intrusion. Vapor barriers are able to block moisture and form a sealed crawl space, thus preventing water from entering and leaking into the home where it can wreak damage.

Crawl Space Insulation Cost and Savings

If you’re requiring insulation on a budget, the good news is that the multitude of factors that you have to choose from for your crawl space insulation allow for plenty of leeway when it comes to determining the ultimate project cost. Because poly is such a reliable material, you will be able to save on costs without jeopardizing durability by using thinner poly to line the crawl space. And since a professional installation can last over two decades, you will be putting your money to good use.

moist crawl space

While crawl space vapor barriers are able to provide invaluable protection for the home, saving countless dollars overtime, the installation process can also lead to rather significant energy savings. While the impact of a sealed crawl space in a humid environment can be easily ascertained, even dry climates can reap the energy saving benefits of crawl space insulation. Sealing a crawl space in a humid environment can earn you an estimated 15% annual energy savings, providing a significant cut in energy use. That benefits both your wallet and the environment.

Crawl Space Vapor Barrier Benefits

If eliminating rot, mold, mildew, fungus, and bacteria doesn’t provide you with enough reasons to invest in crawl space insulation, there are other benefits of crawl space vapor barriers. Not only will your family’s lungs be protected by hazardous fumes, but the integrity of your home will remain firmly intact. In turn, this will greatly impact your home’s value, with the added insulation allowing the value to remain stable and steadily rise over time. Fungus tends to act fast, rapidly deteriorating building materials while harming residents, so guarding against it is a highly cost-effective preventative measure.
While crawl space vapor barriers can save the structure of your home, they can also assist with protecting other aspects of your building. Crawl space insulation reduces the risk of wiring and electrical hazards that could potentially be quite dangerous. Moisture mixing with electrics can lead to rusted wires, electrical shorts, and even fires. Avoid the risk of electrocution and damage by protecting your electronic equipment and wiring from water intrusion. Additionally, crawl space insulation will prevent moisture from collecting on pipes, a process that can lead to them rusting and breaking over time. Overall crawl space vapor barriers allow you to preserve and protect many areas of your home.

Are you ready to invest in the long-term health of your building?

Avoid costly water damage repairs and mold removal by blocking moisture out of your home with crawl space vapor barriers. At California Foundation Works, we’ll assist you in selecting, measuring, and installing the best crawl space insulation for your situation.

Call today to chat with a representative about your crawl space insulation needs and questions!

Call California Foundation Works today
to book your FREE* Crawl Space Moisture Inspection
323-418-2239