Top 5 Crawl Space Encapsulation Mistakes

So why are there so many crawl space encapsulation mistakes? There is no standard when it comes to encapsulating your crawl space. You have spec home builders that are building crawl spaces one way, and you have custom home builders building crawl spaces another. And guess what? They're both acceptable by codes enforcement. Just remember, crawl space encapsulation mistakes could cost you thousands plus headaches for years to come so make sure if somebody's mentioning to you that you should do these five things, you may want to get a second opinion.

Mistake #1

"We don't need to remove that batting insulation to address the mold." Really? My question is how are you, as a homeowner, going to be sure that the company you're hiring to address the mold has addressed the mold if they didn't remove the batting insulation?

"Mold can't grow behind insulation, right?" Wrong! Mold can grow anywhere, on any organic material. A lot of times the paper that is on the back of the insulation traps moisture between the subfloor and the insulation giving it a more opportune time to grow.

"But I thought the paper couldn't grow mold?" Wrong again! That craft paper... we have pulled thousands and thousands of square feet of crawl space insulation to find mold all over the paper backing that was put on there. Yes! The paper can grow mold. If the paper's growing mold, the floor joists and the subfloor can be growing mold. So make sure you pull that insulation out to ensure that the mold is addressed properly.

Mistake #2

Crawl space encapsulation companies will tell you to just put a disinfectant on the mold. Just spray it, you don't have to remove it. That is a huge mistake.

So what do I mean by removing the mold? I mean physically removing the mold. If you apply disinfectant to wood without physically removing the mold, in other words, you're attempting to kill the mold but you don't want to remove it. If you apply that disinfectant to the wood, you're going to have issues later whenever you go to sell the house. The home inspector's going to crawl up underneath there [and believe it's live mold].

You need to include mold removal as part of the disinfection process.

Mistake #3

Another mistake that people often make when encapsulating their crawl space is they choose not to insulate the crawl space. When you go to sell the house, if the house isn't properly insulated, then you're going to have issues moving.

You have to insulate it anyway, so why not just go ahead and take care of the insulation? You can enjoy the comfort & energy savings of having an insulated crawl space.

By the way, before I move on I think it's important to note that building code does require crawl spaces to be insulated.

Mistake #4

Crawl space encapsulation companies will actually tell the homeowner that the dehumidifier will kill the mold. That is not true! Dehumidification does not kill mold.

Mistake #5

Okay, the last mistake that we find a lot of crawl space encapsulation companies do is use the heating and air system to control humidity in the crawl space. But what you've got to take into consideration is two things.

Number one, if this is a remodel job, or if you're in an existing home, chances are that the AC unit that they installed is not properly sized to include that crawl space.

Number two, even if you do have a properly sized heating and air unit, let me throw this out there. What if you decide not to run your AC in the spring and the fall? The problem is that if the AC isn't running then the humidity in the crawl space is getting out of control.

We have done many mold remediation projects for homeowners that have decided or got talked into conditioning their crawl space with their heating and air unit.


This is a lightly modified transcript from our YouTube video, Crawl Space Encapsulation Mistakes | Crawl Space Repair Mistakes.

About Michael Church

Michael Church has been involved with indoor air quality since 2005 and feels the unhealthy crawl space is one of the major problems causing poor indoor air quality.