A crawl space vapor barrier is crucial to the long-term care of a home because it prevents the growth of mold and prevents the introduction of hazardous gasses, like radon, into the air inside the building. Therefore, homeowners and contractors need to keep a close eye on their vapor barrier and replace it when necessary.
“A crawl space encapsulation system is only effective if the vapor barrier is installed correctly and remains puncture free. ,” says Jason Treiger, Account Manager at Americover Inc. “If you need a replacement vapor barrier, we can help guide you toward the product that best fits your budget and environment.”
What is the purpose of a Crawl Space Vapor Barrier?
Vapor barriers are low-permeability polyethylene sheets that are installed on the inside of your crawl space, without punctures or openings, creating a barrier between the building and the ground. The purpose of a vapor barrier is to:
- Stop ground moisture from entering your home or building
- Prevent moisture damage and corrosion to the foundation
- Protect indoor air quality from hazardous gasses and toxins in the dirt or soil beneath your home
A vapor barrier keeps moisture away from the building materials by creating a barrier between the vapor and the wall in which water condensates. This is especially important in climates where the moisture is high, as the process of condensation occurs when moist, warm air meets the cool, dry air. Excess moisture in building materials can result in mold, rot, mildew, and more.
Related article: What is a Class A Vapor Barrier Material?
How Long Does a Vapor Barrier Typically Last?
A vapor barrier is meant to last many years, but the condition of the installation, environment, and climate are just a few factors that will ultimately determine how long a vapor barrier will last. If a crawl space is more susceptible to wildlife, like possums and raccoons, it is not uncommon for pests to chew through plastic sheeting for encapsulation. Environmental impacts such as flooding, and old leaking pipes can require you to replace your vapor barrier much sooner than anticipated.
Common Signs it’s Time to Replace a Vapor Barrier
The most important thing to remember when considering whether it is time to replace a vapor barrier is that often, an encounter with excess moisture inside the home may be caused by a larger issue. It is critical to solve the current issues before installing a new vapor barrier, or you will continue and even exacerbate the current problem.
Leakage and Water Problems
If leaks and moisture problems have been found in the crawl space, it is likely time to replace the current crawl space encapsulation system after the source of the leak or drainage issue has been addressed.
If the plastic sheeting experiences an event that could have damaged it, such as a large flood, erosion, or wildlife nesting in the sheeting, it is likely time to replace the sheeting with a healthy, new plastic.
Punctures and Tears
Any puncture or tear to plastic sheeting compromises the integrity of the sheeting. If the punctures or tears are too large to repair with tape, the sheeting must be replaced immediately.
If the sheeting is no longer up to code standards, for instance, those outlined by NFPA and ASTM, then it may be time to replace crawl space plastic with new plastic which meets current building requirements.
It is additionally important to remember that to change plastic sheeting, you must uninstall the old sheeting and reinstall the new one. Covering the old with the new in an attempt to save time, is fundamentally detrimental to the purpose of installing a vapor barrier.
What are the Best Crawl Space Vapor Barrier Options?
Below are some recommendations by Americover experts on the best crawl space vapor barriers:
Pro Crawl Anti-Mold Vapor Barrier with MPT™: this class 1 vapor barrier passes ASTM E1745 class A, B, & C. Its perm rating blocks more vapor transmission than the leading competitor’s 10 mil vapor barrier with a permeance of only .022 perms and it is embedded with a patented mold prevention technology.
VaporBlock® Plus Vapor Barrier: this high-performance 20 mil under-slab vapor barrier is designed to retard moisture migration and radon gas through concrete slabs-on grade while exceeding ASTM E-1745 Class A, B, and C requirements.
String Reinforced Plastic Sheeting: this durable yet lightweight vapor barrier plastic is available in 6 mil to 20 mil thicknesses so you can choose a heavy duty option for the ground and a lighter option for the walls. Its laminated laminating layers of virgin high-strength polyethylene with a heavy-duty scrim reinforcement between the layers makes it extremely puncture resistant.
Vapor Barrier Yellow: this sheeting is composed of polyolefin resins and offered in 10 mil, 15, mil and 20 mil thicknesses to create a puncture-resistant vapor barrier for use under concrete slabs to stop moisture migration and reduce mold, mildew, and fungus.
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As an Americover customer, you will receive the personalized support of a dedicated account manager to simplify the ordering process and ensure the best solution for every one of your projects. Our friendly, knowledgeable staff is here to answer your questions and fulfill orders Monday-Friday from 7 a.m. to 4:30 p.m. Pacific Standard Time. If you would like to speak with a representative, call us at 760-388-6294 or contact us.