Understanding Crawl Space Encapsulation: What You Should Know

Nearly all homeowners recognize that a dirt-floor crawl space is far from ideal. In fact, we doubt anyone has ever ventured into one and thought, “Wow, this is actually pretty nice!” The truth is, dirt crawl spaces aren’t pleasant — and more importantly, they’re not healthy. Your home functions as a complete system, with the crawl space playing a significant role. In fact, up to 60% of the air circulating in your home originates from the crawl space. The problem? Dirt-floor crawl spaces tend to accumulate moisture, which can lead to poor air quality and even structural issues. The most effective solution is crawl space encapsulation. So, what exactly is crawl space encapsulation, and what does it involve? We’ve created this comprehensive guide to inform and help you explore the best options for your home. Let’s dive in!

What is a crawl space?

Crawl spaces are a type of foundation that provides a gap between the ground and the house. Typically small and unfinished, they are usually about one to three feet in height — hence the name “crawl space.”

Why do homes have crawl spaces?

There are two primary reasons why builders opt for a crawl space foundation:

First, crawl spaces are ideal for homes in areas with high moisture levels. In regions like Florida or the Pacific Northwest, where heavy rainfall is common, crawl spaces elevate the home off the ground, offering protection from potential water damage.

Second, crawl spaces are a more affordable and convenient alternative to basements. Constructing a basement involves digging deep and moving significant amounts of soil, which can be both costly and time-consuming. With a crawl space, builders can avoid these challenges.

Additionally, crawl spaces gained popularity in new home construction from around 1950 to 1970. This period followed a housing shortage caused by the Great Depression and World War II. During these events, home building slowed significantly, but once the war ended and veterans returned, there was a surge in demand as families grew. To meet this need, builders sought to construct homes as quickly and cost-effectively as possible, and crawl spaces provided a practical solution.

What is Crawl Space encapsulation?

Crawl space encapsulation involves sealing off the crawl space from external elements by installing durable, overlapping polyethylene plastic sheets on the walls and exposed dirt floors.

The main goal of this process is to lower humidity levels and protect against leaks, pest infestations, and mold growth. Essentially, it transforms a moisture-prone area into a dry, more controlled environment.

Why do you need to encapsulate your crawl space?

Crawl spaces that aren’t encapsulated mean they have a dirt floor. And dirt floors are not… great. Here’s why:

How does crawl space encapsulation work? A step-by-step guide

Step 1: Inspection Our first step is to thoroughly inspect your crawl space. This is crucial for assessing its condition and determining the most effective encapsulation solutions for your specific situation.

Step 2: Address groundwater leakage If we find significant groundwater seeping into your crawl space, we typically recommend installing a sump pump. This system captures the groundwater before it can enter your home and pumps it to a designated area.

To install the sump pump, we dig a 22-inch hole at the lowest point of the crawl space and redistribute the soil as needed to create a slight downward slope toward the sump hole. This ensures water doesn’t pool elsewhere in the space.

Step 3: Isolate the crawl space from the earth Once we resolve the groundwater issue, we address the water vapor problem. As exposed earth releases moisture, the solution is to cover it with a durable vapor barrier.

We install a thick, 20-mil plastic liner, similar to a pool liner, throughout the crawl space. This vapor barrier is applied to the walls, ceilings, and floors, and secured with fasteners driven into the walls. All seams and obstacles are carefully sealed using specialized tapes and sealants, fully isolating your home from the ground.

Step 4: Seal air leaks After the vapor barrier is in place, we focus on sealing any air leaks. Vents, gaps around pipes, hatch doors, and openings under the sill plate are sealed to prevent unconditioned outdoor air from entering.

Depending on the specific areas, we may use WallCap, an L-shaped molding that covers gaps near the sill plate. Caulk, spray foam, or other appropriate materials are then applied to seal all entry points for outside air.

Step 5: Install a dehumidifier Despite the vapor barrier and sealed air leaks, some air infiltration is inevitable. To maintain optimal humidity levels, we install a dehumidifier, which removes excess moisture from the air and keeps humidity below 55% year-round.

The benefits of crawl space encapsulation

What is Crawl Space encapsulation?

Crawl space encapsulation makes your home a healthier place to live in. Here’s how:

• Improves air quality
• Eliminates pest infestations
• Reduces humidity issues
• Lowers heating and cooling costs
• Prevents mold growth
• Eliminates bad odors
• Prevents structural damage

How much does crawl space encapsulation cost?

If you’re thinking about crawl space encapsulation, your top concern is likely, “How much is this going to cost?”

Unfortunately, there’s no one-size-fits-all answer. Crawl spaces vary, and several factors can influence the price, such as:

• The size of your crawl space
• The height of the crawl space
• Its current condition
• The scope of work required

The best approach is to contact a trusted contractor for an inspection and an accurate estimate.

What’s next?

If you’re located within our service area, we’d be happy to schedule an inspection and assess the best solution for your crawl space. As fellow homeowners, we understand how stressful unexpected repair issues can be. That’s why we’re committed to addressing every customer’s concerns with care, precision, and efficiency—guaranteed.

published on Monday, August 19th, 2024