Skip to Main Content

BQ Basements & Concrete is now  GroundworksLearn more.

The Philadelphia Guide to Crawl Space Encapsulation

Are you a homeowner in Philadelphia interested in crawl space encapsulation? Encapsulating your home’s crawl space can help keep moisture out, increase energy efficiency, and reduce pest infestations. An encapsulated crawl space can even be used to store things like tools and holiday decorations. 

In this blog post, we will provide an overview of what crawl space encapsulation is, why you don’t want moisture in your home’s crawl space, how moisture enters a crawl space, and more. 

Why You Don’t Want Moisture in Your Home’s Crawl Space

Moisture in a crawl space can lead to a whole host of problems. One of the big ones is mold growth. Excess moisture in the air creates the perfect breeding ground for mold spores – and not only is mold unsightly and smelly, but it can also pose health risks for you and your family. This is because some of the air in the crawl space flows into your home’s living area. 

But that’s not all; moisture can also lead to wood rot, weakening your house’s structural integrity. Additionally, if termites or other pests find their way into your crawl space, they can cause even more damage.

And here’s something you might not have thought of: excess moisture in your crawl space can actually lead to higher energy bills due to something called the “stack effect.” Basically, the stack effect is when warm air rises and escapes through the upper levels of your house, while cooler air is drawn in from the crawl space. If that air is moist, it can increase the humidity level in your living area, making your heating and air conditioning work harder and leading to higher energy bills.

Sources of Crawl Space Moisture

  • Open vents – Open vents can allow humid air into the crawl space, condensing on cooler surfaces and creating moisture. 
  • The dirt floor – The crawl space’s dirt floor can also be a source of moisture, especially if it isn’t covered with a vapor barrier. 
  • Cracks in the foundation wall – Foundation wall cracks can allow water to enter the crawl space.
  • Plumbing leaks – Even tiny leaks can cause moisture to build up over time.

What Is Crawl Space Encapsulation?

Crawl space encapsulation is the process of sealing the vents and then placing a thick, vapor-retarding barrier on the crawl space floor and walls. This seals off the crawl space from moisture and outside air.  

The Benefits of Crawl Space Encapsulation

Crawl space encapsulation helps prevent moisture buildup, which can lead to mold, mildew, and other unpleasant issues like wood rot that can damage the home’s structural integrity. By sealing off your crawl space, you can help keep it dry and free from these problems.

Encapsulation can also help improve indoor air quality by reducing the amount of pollutants and allergens flowing into your home’s living area from the crawl space. This can be especially important if you or your family members have allergies or respiratory issues.

Crawl space encapsulation can also potentially reduce energy costs. When moisture levels are high in your crawl space, it creates a damp environment that seeps into your home and causes your air conditioning and heating to work harder to maintain a comfortable temperature. By encapsulating your crawl space, you can keep your home’s air dry, which means potential energy savings. 

The One Con of Crawl Space Encapsulation

The only real downside to crawl space encapsulation is the cost. It’s not cheap, but it’s definitely worth doing. With so many benefits – including improved air quality, increased energy efficiency, and protection against moisture – it’s a smart investment for any homeowner. We have a variety of financing options available through GreenSky® that will make it easy for you to start a home improvement or repair project.

How Crawl Space Encapsulation Is Done

Step 1: Clean the Crawl Space and Seal the Vents

The first step is to clean the crawl space thoroughly. This means removing any debris or old insulation that might be there. Any mold or mildew that may have grown in the space will also be treated. Finally, the crawl space vents are sealed. 

Step 2: Insulate the Space

The next step is insulating the space with a high-quality insulation material. It’s important to choose a material that won’t absorb moisture. This will help keep the space warm, saving you money on energy bills in the long run.

Step 3: Install a Vapor Barrier

After insulating, it’s time to install a vapor barrier. This is a thick plastic sheet that covers the entire floor and walls of the crawl space, creating a seal which prevents moisture and dampness from entering the space. 

Step 4: Install a Dehumidifier

Finally, you’ll want to install a dehumidifier in the crawl space. A dehumidifier helps regulate the humidity level in the space, preventing mold and mildew growth and keeping the air dry. 

For more information, see How to Encapsulate a Crawl Space in 7 Steps.

What About DIY Crawl Space Encapsulation?

Now, I know what you might be thinking: “Why can’t I just do this myself and save some money?” While it’s certainly possible to do DIY crawl space encapsulation, it’s important to note that it’s a difficult and time-consuming process. Plus, if you don’t do it correctly, you could end up causing more harm than good. We strongly recommend letting a professional handle the job. 

Step It Up a Notch by Adding a Crawl Space Drainage System

By adding a crawl space drainage system to your crawl space after encapsulation, you can further protect your home from moisture damage and improve its overall longevity.

What Is a Crawl Space Drainage System?

A crawl space drainage system is a way to keep groundwater away from your foundation. It does this by collecting water that seeps into the ground around your house and then redirecting it somewhere else. This helps prevent water from building up around your foundation and entering the crawl space.

Other Things You Can Do to Help Keep Your Crawl Space Dry and Prevent Problems

In addition to encapsulation and a drain tile system, there are a few other things you can do to help keep your crawl space dry. All of these involve controlling groundwater around the foundation:

  • Regrade your yard, if necessary – This means making sure the ground around your foundation slopes away from it. You don’t want groundwater draining toward the foundation.
  • Install downspout extensions – These extensions will carry runoff farther away from your foundation before release. 
  • Clean your gutters regularly – It’s important to clean gutters regularly so that debris doesn’t build up and cause water to overflow, run down the side of your house, and soak the ground around the foundation.

If you’re considering crawl space encapsulation for your Philadelphia home, contact us today to schedule a free crawl space inspection and receive an estimate!  

Publish Date:

Last Modified Date:

BQ Service Area Map

Our Locations


1227 Liberty St., Suite 206
Allentown, PA 18102

New Jersey

535 Route 38 East, 149E
Cherry Hill, NJ 08002


106 Park Drive
Montgomeryville, PA 18936

West Chester

1503 Mcdaniel Dr., Suite 4
West Chester, PA 19380