Skip to Main Content

Negatives of Crawl Space Encapsulation

When it comes to crawl space encapsulation, there are certain things you should and should not do to ensure you get the most out of encapsulation.

Fully encapsulate crawl space in Virginia and Maryland

Crawl space encapsulation is a process of sealing off the crawl space beneath a building by installing a moisture barrier, insulation, and a ventilation system. The aim is to prevent moisture from entering the crawl space, which can cause structural damage and create a breeding ground for mold and mildew. However, despite its overwhelming benefits, crawl space encapsulation, in some cases, also has some minor downsides. Here, we’ll explore four of these disadvantages.

How Crawl Space Encapsulation Works

Let’s take a closer look at how crawl space encapsulation works. It is a process that involves several essential elements that must be applied together to create an effective barrier against moisture and humidity. Without proper encapsulation, the crawl space becomes vulnerable to dampness and other environmental factors that can damage your home’s structural integrity.

The primary elements of crawl space encapsulation include:

  • Vapor Barrier: This is a layer of plastic sheeting installed over the crawl space floor and walls to prevent moisture from entering. The barrier is usually made of high-density polyethylene and is thick enough to withstand punctures and tears.
  • Vent Removal: Openings and vents that allow external air and moisture to enter the crawl space should be removed. By sealing off these openings, the crawl space remains insulated from the outside environment.
  • Insulation: Adding insulation to the walls and floors of the crawl space can help regulate temperature and humidity levels. Insulation also serves as an added barrier against moisture and helps reduce energy costs.
  • Drainage: High moisture levels in the crawl space can lead to standing water, mold growth, and other issues. Installing drainage systems, such as French drains or sump pumps, can help prevent moisture buildup.
  • Dehumidifier: Installing a crawl space dehumidifier can help control humidity levels and prevent mold growth. A dehumidifier works by removing excess moisture from the air and releasing dry air back into the crawl space.
crawl space encapsulation installation in Virginia

Some Possible Disadvantages of Crawl Space Encapsulation

  1. Cost

Crawl space encapsulation can be an expensive process, depending on the size of the crawl space and the extent of the work needed. Installing a moisture barrier, insulation, and a ventilation system can require a significant investment, which may be beyond the means of many homeowners. Additionally, if the crawl space has existing problems such as mold or structural damage, these issues will need to be addressed before encapsulation can take place, adding to the overall cost.

  1. Lack of Access

Once a crawl space has been encapsulated, it becomes much more difficult to access for repairs and maintenance. For example, if a plumbing leak occurs in the crawl space, it may be challenging to locate and fix the problem because the encapsulation material will need to be removed to gain access. This lack of access can also make it harder to inspect the crawl space for potential problems, such as pest infestations or water damage.

  1. Ventilation Issues

Proper ventilation is essential in a crawl space to prevent moisture buildup, which can lead to mold and structural damage. However, encapsulation can create ventilation issues if not done correctly. If the ventilation system is not properly designed, it can create negative pressure in the crawl space, which can draw in humid air from outside, leading to moisture buildup. On the other hand, if the ventilation system is not adequately sealed, it can allow outside air to enter the crawl space, negating the benefits of encapsulation.

  1. Potential for Gas Buildup

Encapsulating a crawl space can also create a potential for gas buildup. If the crawl space contains gas-producing materials, such as decaying organic matter, the encapsulation can trap the gases inside. This can create a hazardous situation, as the buildup of gases can lead to explosions or health problems. To prevent gas buildup, it is essential to ensure that the crawl space is properly vented and that any gas-producing materials are removed before encapsulation.

bad crawl spaceCrawl Space encapsulation with pillars

Should I Encapsulate My Crawl Space?

Despite the minor disadvantages of crawl space encapsulation, the benefits of this process cannot be ignored. Encapsulation can prevent moisture buildup, improve indoor air quality, and protect the structural integrity of your home. However, it is crucial to consider the potential costs, lack of access, ventilation issues, and potential for gas buildup before deciding to encapsulate your crawl space.

To ensure that the encapsulation is done correctly and safely, it is highly recommended to consult with a professional contractor with experience in this area. This is not a DIY project because there is too much room for error, and an inexperienced individual may end up causing more harm than good. With the right team, however, encapsulating your crawl space can be a wise investment in the long-term health and safety of your home.

Publish Date:

Last Modified Date:

JES Foundation Repair service area map of the Mid-Atlantic region.

Our Locations


8361 Town Center Ct
Nottingham, MD 21236


311 Central Rd.
Suite 2-02
Fredericksburg, VA 22401

Hampton Roads & NE NC

2569 Quality Ct
Virginia Beach, VA 23454

Northern VA & DC

7940 Gainsford Ct.
Bristow, VA 20136


309 Quarles Rd
Ashland, VA 23005

Southwest Virginia / Roanoke

2033 Cook Dr.
Salem, VA 24153

Western Virginia

456 Old Courthouse Rd
Appomattox, VA 24522


45 W Boscawen St,
Winchester, VA 22601