10 Steps to Install Vapor Barrier and Seal Out Moisture
Installing a plastic vapor barrier is a logical way to protect your home's crawl space. Get a step-by-step guide to installing a vapor barrier system in your home.
Let’s be honest, your crawl space is likely a place you never go. The area is damp, dusty, and all around dirty, so it’s no surprise.
But what if that wasn’t the case? What if you could create a clean, dry, usable space with a vapor barrier?
Thanks to modern innovation, vapor barriers are some of the most effective crawl space waterproofing tools on the market. In this article, we’ll explore why installing vapor barriers are beneficial, and how to install one beneath your home.
Why Installing a Vapor Barrier is Important?
About 15 percent of homes built since 2013 have a crawl space foundation, making it important for homeowners to understand the why having a vapor barrier below their home is valuable.
Surprisingly, moisture poses a huge threat to your home. When water (or water vapor) gets below your home, it eventually spreads to wooden structural supports found in the crawl space. This leads to serious problems like mold, wood rot, or structural integrity issues. A wet, damp crawl space is also an ideal breeding ground for insects and rodents.
Sealing your crawl space with a vapor barrier is a great way to keep your crawl space healthy. Doing so can ensure that your family is breathing clean, conditioned air and wooden support beams below your home stay safe.
Keep in mind, vapor barriers alone are not enough. They are just one part of the crawl space encapsulation process. For the most efficient protection, we recommend installing dehumidifiers, crawl space drains, and thermal insulation alongside your vapor barrier.
How a Vapor Barrier Works?
In brief, vapor barriers are a simple way to seal out moisture in your crawl space. According to the US Department of Energy, controlling the moisture in your home can make your home more energy-efficient and less costly to heat and cool.
A vapor barrier does just this. Without a doubt, installing one prevents water vapor and ground moisture from entering the crawl space and causing problems.
Remember that a crawl space vapor barrier can only offer its full benefits if it is airtight—air from outside must not be able to sneak in through walls, vents, or the floor. This is where encapsulation from a trusted, professional foundation company like Groundworks comes in.
Is Mold Removal Necessary First?
One of the common crawl space red flags is mold. Mold is often the first indication of a problem. So, is it important to remove the mold before installing a vapor barrier?
Of course, the answer depends on how long the problem has been festering and how much mold is present at the time of installation. The United States Environmental Protection Agency says if mold is less than 10 square feet (or a 3ft. by 3ft. area), you can clean the mold yourself. They suggest a mold remediation company to address the issue if the area with mold is larger.
Mold needs three things to survive: water, food, and oxygen. Without these three elements, mold will cease to exist. Since oxygen and food (dead organic materials) like wood, aren’t going anywhere inside your crawl space, removing water is the easiest way to prevent mold below your home.
In this case, installing a vapor barrier during encapsulation removes water from the equation. However, if your crawl space has a large amount of mold, it’s a good idea to have it removed by a professional before moving forward with a vapor barrier installation.
How to Install a Crawl Space Vapor Barrier Step by Step
As mentioned, installing a vapor barrier is one step in the overall encapsulation process. Below you’ll learn the grueling steps of encapsulation installation and see why it’s essential to keep outside air out. Your local Groundworks team has repaired nearly ten thousand crawl spaces this year alone. Avoid the dirty work, our experienced team is in and out of your home, leaving your crawl space, clean, dry and ready for storage.
First, before installing a vapor barrier, it’s important to do a full foundation inspection and determine the cause of the crawl space problem. Is groundwater entering from the floor or walls? Are open vents trapping humid air inside? Is a plumbing leak dripping into the space? Ensuring the solution matches the root problem goes a long way to preventing future problems.
Your local Groundworks inspector will consider your neighborhood’s unique soil type, the typography of your home, and the weather conditions before making repair suggestions.
Then, the crawl space needs to be cleaned.
Depending on the condition of the crawl space, this step may look different for everyone. If your crawl space is wet, it’s beneficial to dry it out with a submersible pump, fans, or a dehumidifier. Sometimes, this process may take a while. Consider mold remediation if needed.
All fallen insulation and scrap building material should be bagged and removed.
Next, the floor of the crawl space should be clear of large rocks and debris. This also includes any pests that might be inside the crawl space. Moreover, collapsed insulation needs to be removed as well. Finally, the soil should be raked to establish a rough grade.
Afterward, depending on the amount of water in your crawl space, consider installing a specially designed crawl space sump pump or other drainage options to remove any water that would remain beneath the vapor barrier.
Then, the climate and the amount of energy saving you wish to see will determine the proper wall insulation needed at your home. Regardless, all vents should be sealed completely, and either a ridged wall board insulation or high-quality vapor barrier should be attached to the crawl space walls using a masonry fastener.
After this, all seams that allow air to enter the crawl space should be sealed using quality polyurethane foam. This ensures that small amounts of water vapor won’t be able to leak inside.
Next, to prevent cold air from entering the crawl space, install R30 Fiberglass insulation into the bond cavity.
Now, measure and cut a high-quality vapor barrier to fit the crawl space and allow several inches to run along the walls. Be sure to overlap seams for taping.
Then, use a two-sided butyl tape to create an airtight seal on all seams. Finishing tape should be used to provide secure attachment between the vapor barrier and the walls, floor, and support columns. Not to mention, it creates a clean finish that gives your crawl space a brighter, more inviting look.
Finally, now that your crawl space has been sealed, you need to establish a positive airflow. This can be accomplished by tapping into your HVAC unit or installing an energy-efficient dehumidifier.
Groundworks: Vapor Barrier Experts
While the solution to install a vapor barrier in your crawl space is fairly straightforward, the job can be exhausting, back-breaking work. In addition, with your crawl space being a tight, small area, it’s not uncommon to be working on your back or stomach during the duration of the work. Moreover, this doesn’t mention the numerous trips through the crawl space access point, which can be difficult.
The experts at Groundworks install vapor barriers and encapsulate crawl spaces every day. In fact, in the first eight months of 2022 alone, we repaired nearly 8,000 crawl spaces nationwide. As a result, we have the best products and procedures to make installation as simple and effective as possible. Our 20 mil CrawlSealTM liner locks out moisture and soil gases and comes with a nationally backed, long-term warranty.
If you’re noticing sagging floors or high energy bills, your crawl space problem won’t get better with time. Let Groundworks install a vapor barrier and encapsulation system to seal and eliminate your crawl space problems.
In conclusion, let us do the hard work. Call to schedule your free inspection today or book online. Schedule a time and date to have an inspector put eyes on your problem and suggest solutions that don’t involve you losing your weekend beneath your home.