How Much Does Crawl Space Encapsulation Really Cost?

When a crawl space experiences regular issues with moisture, it can cause water damage, rot, and mold growth. If left untreated, the foundation of the home may start to crack, threatening the stability of the structure. Crawl space encapsulation, paired with any necessary waterproofing and foundation repairs, can resolve moisture problems, as well as improving the energy efficiency of the home.

Crawl space encapsulation involves sealing and insulating the crawl space. On average, this crawl space encapsulation costs $5,500, though the overall cost can range from $1,500 to $15,000, depending on the size and condition of the crawl space.

What Is Crawl Space Encapsulation?

Crawl space encapsulation is the process of installing a water vapor barrier on the floors and walls, as well as wrapping any pillars and addressing any existing leaks or foundation damage. The idea is to create a completely clean, dry capsule-like space, often using heavy-duty polyethylene.

By sealing the crawl space, you can reduce the heat transfer through the walls to improve the energy efficiency of your home. Encapsulating the crawl space can also improve the air quality.

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6 Signs You Should Need Crawl Space Encapsulation

There are a few signs that can indicate that you should encapsulate your crawl space to protect against water damage, rot, mold growth, and other moisture-related issues.

• High indoor humidity can lead to mold growth and make the home attractive for pests. Encapsulating the crawl space can help control indoor humidity levels, though you may also need to invest in a dehumidifier.
• Condensation on the inside of the windows is another sign that the crawl space has moisture-related issues.
• Musty odors are typically associated with mold and mildew growth. Even if you cannot see it, it’s worth having the crawl space inspected and treated for mold growth before having it encapsulated.
• Visible mold is a clear sign that you need to take action. Mold thrives in warm, dark, damp locations, like crawl spaces.
• Pest issues may be unrelated to moisture problems, but in many cases they tend to occur at the same time. This is because damp, dark environments are highly attractive for many insect and pest species. Hire a pest professional to handle the infestation, then get the crawl space encapsulated.
• High heating or cooling bills may be due to gaps, holes, and cracks in the wall or floor of the crawl space. Repairing any foundation problems and encapsulating the crawl space can help to reduce heating and cooling bills, while improving the efficiency of the home.

Pros and Cons of Crawl Space Encapsulation

“The costliest aspects of encapsulating a crawl space are usually securing the area and installing heavy duty vapor barriers or liners,” says Ryan Norman, owner and operator of Norman Builders. “These help control moisture and prevent pest infestation, but can require hours of labor and expensive materials to properly seal and insulate the space.”

Crawl Space Encapsulation Cost Factors

Size

Simple crawl space layouts in a relatively small, but accessible space cost the least to encapsulate, with an average range between $2 to $4 per square foot. Larger and more complex crawl spaces that may be more difficult to access will cost between $3 to $10 per square foot.

Generally, the larger the crawl space, the higher the cost for both materials and labor. If any cleaning or repairs need to take place, the size of the crawl space can influence the cost of these additional services.

• Small, 1,000-Square Foot Crawl Space: $5,000 to $7,000
• Medium, 2,000-Square Foot Crawl Space: $8,000 to $12,000
• Large, 4,000-Square Foot Crawl Space: $15,000 to $20,000

Condition

If the contractors need to perform repairs, like patching the foundation or fixing water damage, the cost to resolve the problem can range from $2,000 to $7,000.

“Any existing damage like flooding, mold, or structural issues must be addressed before installation can begin,” Norman says.

Labor

Some people may be able to handle a crawl space encapsulation job on their own, but if you decide to hire a contractor, plan to spend about 50 to 70 percent of the total project budget on labor costs. This works out to about $2,250 to $10,500 for a 1,500 square foot home.

The reason for the high labor cost is the time it takes to complete the work. “The entire encapsulation process typically takes three to five days,” Norman says.

Foundation Waterproofing

Encapsulating the crawl space is not enough to completely waterproof the area if the foundation has multiple cracks, shows signs of previous leaks, or is currently leaking. Before encapsulation can take place, the foundation will need to be patched and properly waterproofed to prevent flooding in the future.

On average, homeowners can expect to pay between $1,500 to $15,000 for foundation waterproofing, depending on the size of the home, the complexity of the area, and the condition of the foundation.

Inspection

Inspecting the crawl space is important for determining the size and current condition. Without this information, the encapsulation specialists may not be able to provide an accurate estimate for the project.

Typically, it costs between $100 to $250 for a professional crawl space inspection, though many companies may include this service as a part of the total cost and others may even offer free inspections.

Permits

Whether a permit is required for a crawl space encapsulation depends on the location. Check with your local permit office. Typically, a permit for a crawl space encapsulation job ranges from about $100 to $250.

Materials and Extra Features

Costs for the project can vary depending on the amount of materials and the number of extra features that are installed.

• Dehumidifiers are often offered as an extra because they are one of the most effective options for combating high humidity in the sealed space. Plan to spend between $1,300 to $2,800 to purchase a dehumidifier and have it installed.
• Ductwork additions and repairs may be necessary to reroute the airflow in and around the home. This process costs between $450 to $2,000, on average.
• Insulation installation or replacement can help to control the temperature and humidity in the crawl space. If your crawl space needs new insulation, set aside about $0.60 to $4.50 per square foot, depending on the type.
• Sump pump installation is another common extra feature that may be offered during a crawl space encapsulation project. The sump pump collects and expels standing water that would otherwise build up in the base of the crawl space. Sump pumps cost an extra $650 to $1,800.
• Vapor barriers are typically made of polyethylene plastic sheeting. This material comes in several different thicknesses, but generally has a tight price range of just $0.50 to $0.70 per square foot.
• Vent covers that are designed for an encapsulated space may be required to prevent air from leaking through old or worn vents. Add about $15 to $22 per vent cover.

Crawl Space Encapsulation Maintenance Costs

Regular Inspections

A crawl space inspection will typically take place before the crawl space is encapsulated to identify any problem areas. Many companies will include the initial inspection in the total cost, but it’s a good idea to have the crawl space inspected about once every one to two year as well. Plan to spend about $100 to $250 to have the crawl space inspected once every one to two years.

Pest Control

After encapsulation, it’s worth it to schedule regular pest inspections with pest control specialists in the area. The average cost for pest control services is about $384, though this price can vary.

Humidity Control

To avoid mold growth or moisture-related issues, monitor the humidity in the crawl space. Some installers may even suggest modifying the existing HVAC system to account for altering airflow inside and around the house.

Minor HVAC modifications are relatively affordable, but if the ductwork needs to be moved or replaced, it can cost up to $2,500. In most cases, installing a dehumidifier is the best option for handling crawl space humidity problems. On average, it costs about $1,300 to $2,800 to purchase and have a dehumidifier professionally installed in the crawl space.

Best Time of Year to Save on Crawl Space Encapsulation Costs

Plan your crawl space encapsulation for early spring or late fall, when demand is low. Keep in mind that if the crawl space can only be accessed from outside, weather conditions may impact accessibility, leading to a longer installation period and higher labor costs.

DIY vs. Professional Costs

Crawl space encapsulation is a project that can be handled by an experienced DIYer with the right tools and equipment for about $1,000 to $4,000. Though it is a demanding process that can take substantially longer for a DIYer to complete than a trained professional.

In some locations, crawl space encapsulation needs to be done by a professional to be considered up to code, so it’s important to check local regulations. In most cases, it’s best to hire a professional for crawl space encapsulation jobs. They have the tools and experience to complete the project efficiently and at a higher quality than most DIYers could achieve.

You can also rely on a warranty or guarantee for the work in case something does happen to go wrong with the installation.

“Hiring a professional ensures it’s done right the first time, saving money and headaches in the long run,” Norman says.