Vapor Barrier for Crawl Spaces

Buy American Made Crawl Space Vapor Barriers

The SilverBack™, DiamondBack™ and now the new GuardianLiner™ (with anti-microbial) crawl space vapor barriers all offer a lifetime of service in your home. Their high quality does not mean they will break the bank to do it right. Thousands of homeowners encapsulate their crawl space with our products every year and get outstanding results. Read the customer reviews for yourself and look at all of the crawl space products we offer at the same time.CrawlSpaceVaporBarrier.NET

If you need help with how to install these crawl space repair products we can help with that too. We work with hundreds of customers every month with their install and product questions. You can find great advice, installation tips and how-to videos at

Compare the features of these crawl space vapor barriers side by side at

20 Mil Crawl Space Vapor Barrier

12 Mil Crawl Space Vapor Barrier

8 Mil Crawl Space Vapor Barrier

Crawl Space Repair Products

Crawl Space Dehumidifiers

  • Crawl Space Dehumidifiers
    When it comes to crawl space dehumidifiers, quality means everything. A good high quality dehumidifier in the crawl space is extremely important. Unfortunately for homeowners, there’s several out there that just doesn’t perform the way you need. In the end, you’re left with a system that doesn’t work and a large bill to boot. Crawl […]
  • Large Capacity Dehumidifiers
    When it comes to crawl space dehumidifiers, there’s two main brands we trust. Santa Fe and Aprilaire. We’ve been using these two dehumidifier brands for years and it’s a product we’ve come to trust and rely on. For those of you that need large capacity dehumidifiers for your crawl space, we suggest the following units. […]
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  • Compact Air Plus Dehumidifier
    The Compact Air Plus™ dehumidifier is a high quality product that was specifically built for encapsulated crawl spaces. Compact Air Plus™ Dehumidifier The Compact Air Plus™ dehumidifier comes with one of the best warranties in the crawl space industry. We’ve come to find that’s because this dehumidifier was specifically built and designed to last for years.  […]
  • Aprilaire Dehumidifier
    The Aprilaire dehumidifier is another top high quality dehumidifier brand for the crawl space and basement. We feel that Aprilaire is right in line with Santa Fe dehumidifiers in terms of performance and competitive pricing. AprilAire Dehumidifier 1830 70 Pint This crawl space dehumidifier has the following features: 5 year warranty 70 pints per day […]
  • Santa Fe Dehumidifier
    The Santa Fe dehumidifier is one of the best crawl space dehumidifiers you can find on the market. While Santa Fe has a wide range of dehumidifiers to choose from, based on our experiences, here’s the dehumidifiers we recommend.   Santa Fe Compact2 The Santa Fe Compact2 was named that for a reason. This dehumidifier […]
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  • About
    Crawl Space Dehumidifier provides homeowners with a trusted platform to learn about crawl space dehumidifiers and the crawl space encapsulation process. For more than 12 years, our professional crawl space team has been helping homeowners improve their crawl space air. We’ve worked with hundreds of crawl spaces over that time and wanted to give everyone […]
  • Best Dehumidifiers For Crawl Space Air
    For those of you that are encapsulating a crawl space, wanting to improve air flow in the crawl space or considering putting something in place, the long list of possibilities can be a daunting task. Face it, there’s a lot to worry about, such a job can get expensive and then there’s the actual products […]
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Crawl Space Ventilation

  • Crawl Space Encapsulation, Does it Work…
    Does encapsulation really work?

    It’s funny because I never hear that question. There are more objections to closing the vents than any other subject. I think the question that is really being asked is; is it worth it? My answer would be; how much is it worth to eliminate the crawl space from having problems? How much does it cost to remediate Mold, or treat for termites? Is it really worth replacing your roof before it leaks? You can see where I’m going with this. You are probably here on this blog because you are having problems or you know someone that is. Aside from fixing anything that is currently wrong it really is an investment in keeping it from getting worse and costing you more. The average cost of repairing rotted joist is about $3500, now that is not for replacing all of them but it does pay for around 10 or 15 to be replaced. We did a job in Linden Michigan in the Fall of 2008 that needed 22 joist and 45′ of main beam replaced. It was a summer cabin the family used on the weekends and during Christmas time. The crawl space was 2200 sq ft and only 18″ high, a bit of a challenge I might add. The homeowner (Tom) knew it needed to be fixed and was having trouble finding a company that wasn’t trying to retire on his bank account. With this amount of damage it wasn’t hard to see why the salesman’s eyes would light up. In the end we installed a drain system and sump pump, closed seven foundation vents, our 16 Mil SilverBack™ and replaced the 22 rotted joists as well as the 45′ of main beam. The price? Well, the structure repair was $8500 and the rest was another $8000. Hardly chump change for a weekend home, but Tom really didn’t have any choice. It was that or ride it out until the floor fell in then walk away. I can tell you story after story about a homeowner that either inherited, bought or neglected a problem crawl space. Either way it still hurts.

  • Crawl Space Vents
    Homes built on a crawl space needs ventilation! Right? Right! Notice I did not say “Needs vents”, that’s because a crawl space does not need the foundation vents (that go outdoors) if, and I quote:
    IRC 2006, Section 408.3 Unvented crawl space
    Ventilation openings in under-floor spaces specified in Sections R408.1 and R408.2 shall not be required where:
    Exposed earth is covered with a continuous vapor retarder.
    One of the following is provided:
    Continuously operated mechanical exhaust ventilation at a rate equal to 1.0 cfm (0.47 L/s) for each 50 ft² (4.7 m²) of crawlspace floor area, including an air pathway to the common area, and perimeter walls insulated in accordance with Section N1102.2.8.
    Conditioned air supply sized to deliver at a rate equal to 1.0 cfm (0.47 L/s) for each 50 ft² (4.7 m²) of under-floor area including a return air pathway to the common area, and perimeter walls insulated in accordance with Section N1102.2.8.
    Plenum complying with Section M1601.4 if under-floor space is used as a plenum.
    So, the answer to the question “Can I really seal them up?” is, YES you can seal them up and you should seal them up once you have selected and are ready to install a continuous vapor retarder. The advantages of sealing the foundation vents goes well past the moisture control aspects. Every winter, that cold kitchen or bathroom floor reminds us that we need to get some insulation in the crawl space. Well, before you can warm anything you have to keep the cold away. Closing the foundation vents will make your heating bill drop, warm your floors, and keep the water pipes from freezing. DO NOT CLOSE YOUR VENTS IF YOU ARE NOT GOING TO SEAL OUT THE MOISTURE FROM THE EARTH. One thing to know about this subject, and any subject regarding crawl spaces, if you try to fix one problem without addressing the other “known” problems there is a great chance you will worsen your crawl space headache. Educate yourself first!

Crawl Space Moisture

  • Vapor Barrier
  • 20 Mil Crawl Space Vapor Barrier
    20 Mil reinforced Crawl Space Vapor Barrier

    Made from premium grade virgin polyethylene resin. Most plastic manufactures can't say that and be truthful! Our SilverBack™ brand crawl space vapor barrier has a new look and comes in three new sizes! The top of the SilverBack™ is still white but the back is now Silver. As always our vapor barriers are true thickness, so our 20 Mil measures 20 Mil at the barrier not the string reinforcement and naturally resists Mold and Mildew. Due to the increased availability of low quality "white" plastic from China being sold as a crawl space vapor barrier we have decided to change how our American Made SilverBack™ vapor barriers looks.

    You get the absolute best quality and performance as well as the technical support you need to install our products and answer your questions. The 20 Mil SilverBack™ is a perfect choice for high traffic areas or for homes that require additional storage in the crawl space. This product is reinforced with a polyester thread for additional tear strength. Use the 20 Mil SilverBack™ on the floor and the 12 Mil SilverBack™ on the walls to keep the costs inside the budget.

  • Crawl Space Insulation
    The hot topic for the fall is, what is the proper way to insulate a crawlspace? There are really two ways to get the most bang for your buck: one is adding insulation in the crawl space in the proper place in the proper way and the other is to close the foundation vents that let in the outside air.

    Let’s talk about proper installation first. The new idea behind insulation in crawl space is to insulate between the inside and the outside of the home rather than insulating between the house in the crawl space. By preventing the cold air from entering the homes envelope you can better protect your home from heat loss. Installing insulation on the foundation walls will get you the greatest result for the cost and effort. With that being said, it is my recommendation that you use extruded rigid polystyrene insulation rather than spray foam polyurethane insulation. The biggest reason I recommend rigid foam over spray foam is because of the amount of moisture the insulation will absorb. Rigid foam absorbs far less moisture than spray foam does. This means, better results for a longer period of time. The Achilles’ heel of all insulation is moisture. This is why fiberglass insulation should not be used in a moist environment like a crawl space, unless of course your crawl space is not a moist environment. The bottom line is everyone has an opinion. My opinion is backed by over 20 years in the building industry and seeing every other way to insulate a crawl space fail miserably.

    Now, let’s talk about the other way to insulate your crawl space. Well maybe insulate isn’t the proper way to say it. It’s more of a preventative then it is a procedure. If you’re air-conditioning your home and you want to keep the cool air inside you won’t open all your windows. The same is true in the opposite, if you’re heating your home you don’t open the windows and let the cold air in. When it comes to insulating a crawl space or preventing your crawl space from getting colder than you want the most effective way, even more than crawl space insulation, is to prevent the cold air from entering the crawl space. It is becoming well known and well excepted that the crawl space foundation vents cost far more harm than they were ever meant to prevent. Closing the event is simply not enough. The vent must be sealed in order to prevent the outside cold air from entering the crawl space. In fact, the best place to insulate in a crawl space is the foundation vents.

    Properly insulating a crawl space and properly handling the foundation vents is critical to saving hundreds of dollars a year in heating costs. Choosing the proper insulation will give you years of effective service. Correcting the problem with the foundation vents however, carries a much larger commitment. Your choices are: to seal your foundation vents before the winter every year and undo that work every spring or you seal the entire crawl space, permanently close the foundation vents, condition the crawl space and treated it as part of the house. It’s your house and you always have final say, but the facts are in and a conditioned crawl space is far more efficient than one that is not.


  • Crawl Space Vapor Barrier
    Crawl Space Vapor Barrier

    The crawl space encapsulation industry combines crawl space dehumidifiers and crawl space vapor barriers together to dry out and solve the problems homeowners are having with their crawl space.

    There is a wide range of quality vapor barriers for the crawl space just like there is a wide range of quality contractors to install them. The fact is there are vapor barriers that are made specifically for crawl spaces and then there is everything else. Contractors on the cheap will install whatever they can buy that costs less. At the same time these contractors will not discount their services like they demanded the crawl space vapor barrier should be. There are far more copy cat products on the market than their are legitimate brands.

    If you feel that you can trust the company you are buying your crawl space vapor barrier from then most likely they are offering you a quality product. But, there are some things to look for:

    Make sure you don’t get to hung up on perm rating, alone it does not represent all things vapor barrier

    Look at the weight of the vapor barrier, yes actual weight per 1000 square feet or MSF. This will make sure you get what you pay for. Take a look at this article

    Look for a manufacture that stands behind their products

    Check the product reviews

    Buying a crawl space vapor barrier is not rocket science, but it does require you to make sure you know what you are buying.