crawl space encapsulation cost

Average Cost for Crawl Space Encapsulation

The average cost to have a professional encapsulate your home’s crawl space is $7,500. Some homeowners choose to buy their own materials, but if you hire a contractor to do the encapsulation they will provide all the materials to complete the project. And you’ll know the job is done right.

Average Do It Yourself cost

$1,500 – $8,000

Average Contractor Installed Cost

$4,000 – $16,000 

Typical Cost Average


Last Updated: Tuesday, January 18, 2022

Overview of Crawl Space Encapsulation

Before we dive further into crawl space encapsulation cost factors, it’s important to know what crawl space encapsulation actually is. What all is included in this process?

Crawl space encapsulation is a multiple-step process that includes installing a vapor barrier on the ground of a crawl space, sealing up all the vents in the space and insulating the walls of the space. Where moisture is a significant problem, installing a dehumidifier in the crawl space is a common practice. And if the ground outside the crawl space is wet, a drainage system to carry moisture away from the foundation is necessary – and pushes costs toward the high end of the spectrum.

When all these steps are completed, a crawl space is fully encapsulated sealed off – encapsulated – from the penetration of air, moisture and potential ground gases like radon from the earth outside the foundation. When properly encapsulated, the crawlspace should be free from issues like mold, mildew, pests, and unhealthy air quality.

Tip: In order for encapsulation to be successful, all the openings to outside air need to be sealed up. If outside air can still flow into the crawl space, it will be working against the encapsulation, and tools like the dehumidifier will be working overtime to make up for it, so make sure to seal up all those cracks!

This crawl space encapsulation cost estimate looks at the cost factors involved in the project and offers tips and advice for homeowners considering crawl space encapsulation.

Crawl space encapsulation is not a popular DIY project, and usually requires some previous experience in order to do it successfully. However, if you are considering doing this project yourself, we offer some DIY tips below.

Product and Installation Supplies Cost Details

Crawl Space Cost Factors

Below we’ve provided a list of cost factors to consider for a crawl space encapsulation. These factors will determine the total cost of your project, and will help you form an accurate cost estimate for your crawl space encapsulation.

  • Size of Crawl Space – The bigger the crawl space, the more it will cost to encapsulate. A larger space means that encapsulation will require more supplies and labor time, and pieces like the dehumidifier will need to be larger to accommodate for the extra space.
  • Crawl Space Condition – Evaluate the condition of your crawl space and take note of anything that needs to be taken care of before encapsulation can be done. Tasks can include filling significant cracks in the foundation, removing mold from surfaces, replacing old windows or caulking their frames to ensure an airtight fit and replacing an old sump pump.
  • Vapor Barrier Thickness – Vapor barriers are available in a range of thicknesses. The most popular are from 6-mil to 20-mils thick, but those up to 60 mils are available. The thicker the barrier, the better protection you will have against moisture seeping through, but a thicker vapor barrier will also cost more per square foot. Still, we recommend using a thick barrier for increased durability.
  • Drainage System Installation – Encapsulation takes care of moisture and humidity, but it is not meant to handle excess water outside the foundation. The two main types of drainage systems that are installed to prevent flooding in a crawl space are sump pumps and French drainage systems, often used together. If you don’t know if you already have a drainage system in your crawl space, you can either check for one yourself or hire a professional to let you know.
  • Type of Dehumidifier – Experts recommend using a dehumidifier that is 50-pints or above for a crawl space. These dehumidifiers run $300 – $650 or more, depending on what brand and size you choose. Getting a good-quality dehumidifier is one of the key’s to a successful crawl space encapsulation when high humidity is a factor.

Retail Material and Equipment Costs

Here’s where your money goes on a DIY or pro crawl space encapsulation.

  • $25 – $80 per Foot | French Drains
  • $150 – $1,200 | Sump Pump – Based on basic pump replacement vs. cutting in and installing a first-time sump and pump
  • $0.30 – $0.70 (30 – 70 cents) per square foot | 12 mil to 24 Mil Vapor Barrier
  • $35 – $45 per 200-foot roll | Vapor Barrier Seam Tape
  • $25 – $40 per gallon | Concrete Sealer in 5-gallon Bucket (covers about 200 s.f. per gallon) – Used on many jobs, but not all
  • $300 – $650 | Basic Dehumidifier – but depending on capacity and features, and whether it is hard-wired, cost can exceed $1,500
  • $60 – $100 | Sealed, Insulated Access Doors
  • $8 – $15 per Tube or Can | Sealing Caulk or Foam for around any penetrations into the space such as a window, dryer vent or furnace exhaust vent.

Permits, Inspection, Related Costs and Installation Time

Permits and Inspection Cost

  • $0 – $200 | If there’s no electrical work, such as a sump pump wiring and installation, as part of the project, you likely do not need a permit. Ask your contractor for details, or if you’re DIY, call your local codes office.

Related Costs and Installation Time

  • 1 – 3 days | Crawl space encapsulation is a multi-step process that can take a bit of time to do the right way. You can expect a professional to spend between 1 and 3 days completing the whole encapsulation. Time is based on crawlspace size, initial repair steps to the foundation, potentially having to cut in a sump crock and installing the vapor barrier, pump, dehumidifier, etc. If you are doing this project yourself, it may take a few more days to finish up.

According to Olshan Contractors, the job proceeds as follows:

  • STEP 1: Crawl space preparation and cleaning (remove debris and hazards)
  • STEP 2: Improve interior and exterior drainage as needed
  • STEP 3: Install vapor barrier, including specialized fasteners or tape to seal joints
  • STEP 4: Seal vents, doors, and utility entry points
  • STEP 5: Install and connect sump pump or dehumidifier units as needed

Costs of Related Projects

Below is a list of related projects that you might be interested in.

  • Block Foundation Repair
  • Crawl Space Insulation
  • Sump Pump Installation
  • Add Electrical Breaker (for Sump Pump or Dehumidifier)
  • Cost of Vapor Barrier in Crawl Space
  • Whole House Dehumidifier Cost
  • Cost to Install a French Drain
  • Black Mold Remediation

DIY or Hire a Pro?

As with many indoor home improvement projects, labor accounts for the biggest chunk of the bill – 50% to 70% according to HomeGuide, or up to more than $10,000 per Home Advisor, figures that are pretty accurate.

That makes it tempting to DIY. Before you go that route, realize that encapsulation must be done correctly. If the area isn’t fully encapsulated and properly sealed, air, moisture and ground gases from outside the crawl space might continue to invade the area, rendering your efforts a waste of time and money. That’s why we recommend hiring pros for this job.

If you’re new to home owning or haven’t needed to call in a pro before, it can be difficult to know where to start. One of the best ways to find a quality company is to ask friends and family if they know of anyone they would recommend. Or use the quick, convenient form on this page to receive written, no-obligation estimates from top  contractors in your area who do crawl space encapsulation.

Look for someone who is respectful and courteous, and who will be upfront with you about a cost and time estimate. Get the cost quote in writing before any work begins on the crawl space to avoid issues down the road. It’s always a good idea to hire a worker from a reputable company with good insurance coverage, even if it costs a little more than the competitors.

Crawl space encapsulation is a complicated job that is difficult to get right without training and experience. Making sure that every crack is sealed up and the vapor barrier is installed correctly is what professionals are trained to do, so don’t feel bad if you don’t feel up for the challenge! We recommend this as a good project to hire a professional to take care of. While it may cost more up front to hire a contractor, you will most likely save money down the road because you have a solid and high-quality crawl space encapsulation. Unless you have experience with crawl space encapsulation, we suggest that you leave this one to the pros!

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *