Pro Guide: What is a Vapor Barrier for a Crawl Space?

A crawl space vapor barrier is an excellent investment for your home or commercial structure. Vapor barriers offer protection against water damage while also helping to keep interior spaces clean and dry. However, you might be wondering, what is a vapor barrier? Also, how does it differ from encapsulation and other waterproofing options?

These are all excellent questions for a property owner to consider! To ensure you’re keeping your structure in good repair, note the answers here. Then, feel free to discuss any other concerns with a waterproofing contractor near you.

What is a crawl space?

First, note that a crawl space refers to the opening underneath a structure with a pier and beam foundation. These foundations lift the structure up so that it sits on those piers or blocks rather than directly on the ground.

Also, it’s good to remember that plumbing pipes and electrical wiring often run along a structure’s underside. In turn, they’re often exposed in that space. A crawl space also exposes wood framing and other structural supports along a structure’s underside.

Due to their design, crawl spaces are notorious for trapping moisture, including airborne humidity and dew rising from the ground. Many contractors will tell you that moisture is the number one enemy of foundations and a structure’s wood framing! In turn, it’s vital that a property owner consider waterproofing options for their structure’ crawl space.

What is a vapor barrier for a crawl space?

A crawl space vapor barrier consists of a thick tarp installed over the ground inside a crawl space. This tarp blocks moisture or dew coming up from the ground, helping to keep the space dry. Additionally, a vapor barrier provides a clean, dry surface for storage or accessing the space.

In contrast, crawl space encapsulation consists of the same types of thick tarps applied over virtually every surface in that space. This might include the structure’s underside as well as along piers that create the foundation.

Full encapsulation might provide more complete protection against water damage in the crawl space. However, vapor barriers are often far more affordable. Also, not every crawl space needs full encapsulation! Structures located in drier areas or with adequate air circulation in the crawl space might only need that ground barrier.

Also, many contractors suggest both a vapor barrier and other waterproofing solution in the space. This might include a dehumidifier, sump pump, or French drain installation. Along with your vapor barrier, these solutions are often all that’s needed to protect against water damage.

Do you need a vapor barrier in a crawl space?

While you don’t need a vapor barrier in a crawl space, their benefits far outweigh their costs. First, vapor barriers protect pipes, wires, and wood framing from water damage. Second, they help block moisture that risks mold growth along a property’s underside.

Also, blocking moisture in a crawl space keeps it from seeping into a structure’s interior spaces. In turn, you reduce the risk of interior mold, mildew, and musty odors. Additionally, crawl spaces mean a cleaner, drier space under a structure. This makes it easier and safer to access the structure’s underside. A clean and dry crawl space also reduces the risk of water damage to anything stored in that space.

Above all, note that a vapor barrier installation is often far cheaper than foundation damage repair or mold cleanup. It might also be cheaper to install a vapor barrier than to replace damaged items you keep in the crawl space. Potential homebuyers might also appreciate that vapor barrier, if you decide to put your home on the real estate market.

Can I install a vapor barrier myself?

While you might find several vapor barrier material options at your local hardware store, there are many reasons to leave this installation work to the pros. One is that vapor barrier tarps you find at home improvement stores typically don’t offer the same protection as commercial quality products. Two, these tarps are thick and heavy and more cumbersome to cut and install than you might realize!

Also, professionals ensure proper sealing of the vapor barrier around your property’s crawl space. Without proper sealing, the vapor barrier is typically pointless! Open areas allow moisture from the ground to seep out from under the barrier and then get trapped in the crawl space. Note that water damage is often far more expensive to fix than the cost of a professional installation.

Additionally, a professional waterproofing contractor can note if your property needs additional solutions, for maximum protection. This can include a French drain installation, to direct moisture under the ground away from the foundation. Dehumidifiers trap airborne humidity before it can settle onto a structure’s underside.

Above all, crawl spaces are often dirty and downright dangerous! They can even be infested with insects and vermin. To keep yourself safe and to ensure quality, rely on professionals for crawl space vapor barrier installation.