crawl space encapsulation

What Is Crawl Space Encapsulation and Is It Worth It?

You’ve got some issues in the crawl space under your pier and beam home: excess moisture, dampness, drainage problems, wood rot, and musty smells coming from under your home. Not good. You’re looking for solutions and are wondering about crawl space encapsulation. Namely, what is it, and is it worth it?

Anchor Foundation Repair Bryan College Station

At Anchor Foundation Repair, we have been assessing and repairing all types of Brazos Valley foundations since 1985. We’ve seen what works and doesn’t work for moisture, dampness, and smells under crawl space homes and what doesn’t. We’ve also seen the results of a few encapsulation projects in our area and can share what we observed.

This article will describe crawl space encapsulation and how it’s supposed to work in theory. Then we will discuss some anecdotal results we have seen in our area, along with our thoughts on when encapsulation might work for a home vs. when other solutions are more appropriate.

*Full-Disclosure Alert* We are not proponents of crawl space encapsulation as a solution for Central Texas homeowners except in a few perfect circumstances. Read on to find out why . .

What Is Crawl Space Encapsulation and How Does It Work?

Crawl space encapsulation involves wrapping the space under your home with a vapor barrier material lining the ground and walls (and sometimes the underside of the joists/subfloor too) of the crawl space. The material used is officially called “heavy-duty polyethylene” but really can be best described as super thick plastic or tarp-like material.

encapsulated crawl space

Before starting an encapsulation, the crawl space needs to be cleaned up with drainage issues already handled and any existing mold remediated. The plastic sheeting material is laid out under your home and any seams ideally are taped up. Existing vents are sealed off and a dehumidifier is typically added to keep the humidity levels down.

The idea is to make a closed and sealed “capsule” of protected space that is clean and dry and theoretically improves conditions under and inside your home. Crawl space encapsulation potentially offers these benefits to homeowners:

dehumidifier in crawl space encapsulation
Dehumidifier in place
  • Improves air quality
  • Keeps out pests and dampness
  • Prevents mold and mildew growth
  • Increases energy efficiency
  • Insulates floors from cold temperatures

Costs for professional crawl space encapsulation can range from $5,000 all the way up to $30,000 with an average of around $15,000. You could also DIY something like this for lower costs but you would need to be prepared for some pretty difficult and likely unpleasant work.

Does Crawl Space Encapsulation Actually Work?

There’s that golden question on your mind about encapsulation: Does it really work?

It’s guaranteed that any contractor that offers crawl space encapsulation services will tell you that it works. So if you’re asking one of them, they will surely tell you that it does.

We do not offer crawl space encapsulation as one of our services. In our experience thus far, we have not seen it live up to all its touted benefits. On the surface, encapsulation very likely improves air quality and energy efficiency for the homeowner. So inside your home, you will feel some benefits and probably think everything works just great. 

encapsulation of crawl space
Evidence of water intrusion

However, if you were to inspect underneath your home after having the encapsulation for several years, the benefits may start to fall apart. We have personally seen water intrusion into crawl space encapsulations and don’t see how you can fully keep water out. 

Water always wins. All that dampness and moisture you were trying to keep out ends up getting trapped inside. Your risk of mold, mildew, and pests goes right back to where it was or worse since now you have no outside ventilation to help remedy the situation.

Plus, if your drainage situation wasn’t adequately handled beforehand, encapsulation might even create more problems for you by fostering more moisture problems, wood decay, and eventually foundation issues

Frankly, not many people choose to have this type of service done in our Brazos Valley area and it seems to be for good reason. 

The encapsulations we have seen don’t appear very thorough or carefully done. We see gaps in coverage, heavily wrinkled sheeting, excess debris, and evidence of water intrusion.

When Crawl Space Encapsulation Is Appropriate

In our professional opinion, crawl space encapsulation only seems appropriate in a few circumstances. Encapsulation may be right for you if:

example of crawl space encapsulation
Make sure that they don’t leave gaps in coverage if you get encapsulation
  • Your home is new construction and positive exterior drainage is planned
  • You have good drainage and plenty of clearance in your crawl space for effective installation
  • You have a drainage remediation plan in place that will handle water intrusion
  • You have health concerns regarding fungus and mold with a persistent musty odor coming from the crawl space with good drainage, clearance, and water remediation plans.

It’s also important to be careful of drain pipes, water, and gas lines that could get covered up during the encapsulation process. If something breaks and needs repairs in the future, encapsulation may make problem detection or any needed repairs nearly impossible without compromising your encapsulated space.

When Crawl Space Encapsulation Isn’t Feasible

example of crawl space encapsulation
This encapsulation included insulation on the sides . . .

Many homes have situations where crawl space encapsulation isn’t the best idea. Encapsulation is not a good fit if:

We see many homes that are too low to the ground coupled with poor ventilation and bad drainage. All these situations are a recipe for issues with mold, wood rot, and foundation problems. Encasing your crawl space does not solve any of those issues, it just covers them up and only delays the inevitable or causes further damage. 

Many homeowners think that encapsulation is a good substitute or alternative for working on these other concerns, but that’s just not the case. You simply can’t hide from these problems with plastic and think that your issues are solved. 

What Are the Alternatives to Crawl Space Encapsulation?

gaps in encapsulation coverage
Gaps in encapsulation coverage

Encapsulation may seem like an easy “pill” to swallow to quickly fix your problem. But much like taking a *capsule* of painkiller for your aches and pains, it just masks the issue. What you really need is to exercise some effort to solve the problem long-term for a healthier home.

We kind of hinted at this in the last section, but working on the issues that likely created your desire for encapsulation might be a better play in a lot of situations. 

Alternatives to encapsulation include taking the time to solve your moisture issues through: 

We’ve got other articles that detail each of these options that you can check out. I know this is a lot to think about and work on. Like anything you are trying to keep in good shape, the fast and easy way isn’t always the best way. Usually, it’s the stuff that takes more diligence that ends up being the most effective in the long run.

Want to Work on Your Crawl Space Another Way?

crawl space encapsulation issues
We won’t leave excess debris in your crawl space like whoever worked on this home did . . .

Now you know a little more about encapsulation and that in most cases we don’t think it’s worth it. If you’re planning to work on the other issues listed above instead, we can help you with one of them and that’s replacing the decayed wood under your home.

At Anchor Foundation Repair, we don’t fix things that don’t need fixin’, and we don’t try to sell you stuff you don’t need. After 35+ years in business, that’s what’s best for our Brazos Valley community and for exceptional homeowners like you. We’re here to help guide you through your home problems, but you’re the one in charge.

Check out this article for more on rotted wood in a crawl space foundation and what it takes to get the job done.