The Dos and Don’ts of Crawl Space Encapsulation

The Dos and Don’ts of Crawl Space Encapsulation
  • Opening Intro -

    A crawl space encapsulation is a technique used in sealing where the foundation walls and floors are lined with overlapping layers of thick polyethylene plastic.

    This technique is very effective in keeping any moisture out of the encapsulated area.


There are a lot of benefits a crawl space encapsulation can provide if done correctly. However, to ensure that the encapsulation is appropriately administered, you must not forget about the dos and don’ts of crawl space encapsulation.

The Do’s of a Crawl Space Encapsulation

First, we will talk about the things that you should do when you encapsulate your crawl space. These Do’s should be observed to ensure that you will adequately seal the crawl space.

  • Do Prepare the Crawl Space for Encapsulation

    Before you start encapsulating your crawl space, you need to prepare the area first. Next, you must address all the issues your crawl space might present. These issues vary depending on the condition of the space itself.

    However, here are some bullet points you must check out to know what issues are possibly present on your crawl space before the insulation process starts.

    1. The first issue to look out for is insufficient drainage. If your home has a poorly built drainage system, water will likely seep its way into your crawl space.

      One way to identify poor home drainage is when you notice water is pooling underneath your home.

      It would be best if you get your drainage system fixed before starting the encapsulation process of your crawl space.

    2. Next to look out for is a backdraft from appliances. Carry out a check of the appliances you have at home.

      Check if these appliances emit carbon monoxide into your living space through backdraft.

      Going and continuing the encapsulation without addressing this issue will endanger everyone living in the house.

    3. Mold Growth is also likely to happen in a crawl space. Molds can mostly be found on the HVAC equipment and floor joists in the crawl space. Resolve this issue as a part of the preparation of your crawl space for encapsulation.

    These mentioned issues are commonly found in every crawl space, including yours.

  • Do Seal Your Crawl Space

    Sealing your crawl space is also an essential step in preparing your crawl space for encapsulation. To ensure that your crawl space is adequately secured and ready for encapsulation, you must install a vapor barrier on the crawl space floor.

    This vapor barrier will help keep out the moisture from entering your crawl space. Next, seal all the openings and vents you can find in your crawl space. This way, the air from outside will be kept out from entering your crawl space.

    Ensure that the seal has no gaps, cracks, or holes. It is best that your crawl space is secure and properly sealed to prepare it for encapsulation. You do not want to install the encapsulation when your crawl space is not yet prepared.

    Making sure encapsulating your crawl space is done successfully because the cost of Crawl Space Encapsulation is rarely cheap. You do not want all your money to just go to waste just because the encapsulation is not done properly.

drainage systemdownspout extensions

      some drainage list to consider      

The Don’ts of Crawl Space Encapsulation

Now that we have already established the things you must do when encapsulating your crawl space let us next talk about all the don’ts you need to avoid.

  • Don’t Use Fiberglass to Insulate The Crawl Space.

    Fiberglass insulation is highly discouraged to use in insulation, especially in between floor joists. This insulation option can absorb moisture quickly, which makes your crawl space decay over time. Thus, fiberglass insulation is not advisable in wet conditions.

    The best material to use for insulation would be foam board or polystyrene insulation. It would be best if you remembered this tip when you start sealing your crawl space during your preparation for encapsulation.

  • Don’t Over Install Vents.

    Some homeowners thought that they needed to install a lot of vents. But what they might not know is that excessive installation of vents can cause moisture to penetrate the space, which can cause molds to grow.

    When installing vents, it is always recommended to follow the standard design for crawl space vents. As a rule of thumb, a vent should be installed one per ten feet. There is a standard design for installing vents on crawl space because it is important not to overdo it.


  • Don’t Use Foam Spray For Insulation.

    Aside from avoiding fiberglass insulation, you must as well stay away from foam spray insulation. Although spray foam is not a lousy insulation option given the crawl space condition, this option should be avoided at all costs.

    Crawl spaces are known to be damp areas, and using a foam spray will only trap moisture. If moisture is trapped, the crawls space will rot, and mold will grow as the moisture leaks to the base.

  • Don’t Forget to Hire A Professional

    Hiring a professional is always the best choice if you are planning to encapsulate your crawl space. These professionals have the proper knowledge of what to do and not to do during the preparation until the installation process.

    Furthermore, these people have the right skills and tools necessary for a proper crawl space encapsulation. Therefore, you will never have to worry about anything as you will rest assured the process is done the proper way.

other related articles of interest:

Putting Everything into Account

You must follow the Do’s and avoid doing the don’ts mentioned in this article. This way, you will ensure that your crawl space will be well-prepared from the encapsulation, which has a significant impact on the installation outcome.

Find Exterior Home Services
Chimney Driveways
Foundations Waterproofing
top-rated, pre-screened local contractors
pdf file FREE: download contractor selection
enter zip code – powered by HomeAdvisor ™


Image credit: by

end of post … please share it!




directory photos forms guide

Helpful article? Leave us a quick comment below.
And please share this article within your social networks.

facebook linkedin pinterest

Amazon Affiliate Disclosure: is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to The commission earnings are used to defray our cost of operation.

View our FTC Disclosure for other affiliate information.

Categories: Home Foundation

About Author

LetsRenovate Admin

From the administrative staff at We hope you enjoy this article and the elements of the site. Please forward any suggestions or comments regarding the posting or other suggestions for improvement. We also operate other helpful guides in education, money, travel, and business. Visit our main site for address information. Thank you. Please share this site with friends and family.