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Bad Vapor Barrier

A good vapor barrier is absolutely essential to moisture control within your home. If you have a bad vapor barrier, you could face serious issues in your home.

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Waterproofing and encapsulation are all-important when it comes to keeping your property’s crawl space dry, safe, and hygienic. This may not seem like much, but Colorado homeowners who have had damp or flooded crawl spaces in the past will know all too well how a damp crawl space can affect a whole property. A high-quality vapor barrier may be just one part of the overall encapsulation process, but it is one of the most fundamental. When a property’s vapor barrier is compromised, every other part of the waterproofing system is affected. 

Before Vapor Barrier

Why Your Vapor Barrier is Important 

Choosing to install a vapor barrier in your crawl space has many benefits, but the most obvious is the creation of a clean, dry, safe crawl space. By keeping moisture on the outside, a vapor barrier prevents the buildup of humidity, the formation of mold and mildew, and makes your crawl space less attractive to pests of all kinds. This means your home as a whole has an extra layer of protection from these issues and all the other problems they can bring. 

Of course, there are other benefits to having a good vapor barrier properly installed. These include, but are not limited to: 

  • Better temperature control in your home 
  • Lower risk of bursting pipes in winter 
  • Lower risk of bad odors in your crawl space 
  • Slightly lower energy usage and bills (improved further with insulation and a dehumidifier) 

And, of course, an encapsulated crawl space is perfect for seasonal storage, meaning you can make the most of every square foot of space your home has to offer. Of course, the degree to which you enjoy these benefits depends on whether you have the best vapor barrier for your home! 

What Makes a Good Vapor Barrier? 

Generally speaking, a good vapor barrier is durable and effective, but this can mean many different things. Vapor barriers can be made from many different kinds of material and come in many different degrees of thickness, for example. While you, as a non-professional, don’t need to know the specifications of each and every type of vapor barrier, it does pay to have some information on the most common kind of domestic vapor barrier: plastic. 

Plastic vapor barriers come in a range of thicknesses and can be made from different grades of polyurethane. When you get your vapor barrier from a Complete Basement Systems crawl space specialist, you can be certain that they are made with the highest-grade materials. There are many options for thickness, however. 

A 6-mil vapor barrier is generally the thinnest available through a professional (though many do not stock them) and they are not very tough. Incredibly prone to tears and punctures, these vapor barriers are not suited for crawl spaces that will see traffic or be used as a storage space. Ten to 15-mil vapor barriers are thicker and offer incrementally better durability and puncture resistance. If you want superior tear and puncture resistance, or you intend to use your crawl space for storage, you should aim for 20-mil vapor barriers; these are some of the sturdiest. They offer superior puncture resistance, tear resistance, mold resistance, and generally have a long lifespan (depending on who manufactures them).   

Of course, thickness is not all you should think about when choosing a vapor barrier. There are many barriers that have additional benefits. For example, consider whether your vapor barrier is treated to make it more resistant to mold spores and can decide whether it is compatible with other popular waterproofing measures.    

Bad Vapor Barriers: The Problem Signs 

Whether your vapor barrier is unsuitable for your home, it has become damaged, or it has simply run through its lifespan, there are a number of problem signs that will help you to identify issues with your vapor barrier. 

Increased Humidity Levels 

If you notice a sudden increase in humidity levels within your crawl space or your home as a whole, you should check your vapor barrier for signs of damage or degradation. If the vapor barrier has recently been installed, you should also consider the possibility that it was poorly installed or simply unsuitable for its purpose. 

You can track changes in humidity by the way the climate in your home feels, of course, but also by looking for condensation on cool surfaces. You may also notice gradual increases in your electricity bills as humidity in your home rises. This is because humid air is hard to heat or cool and, as a result, will make your HVAC system work harder.  

Musty Odors 

A lingering, musty odor in your crawl space is a sure sign of long-term dampness and humidity in this area. Unless you can identify a clear alternative cause for this, it could well be that the cause of this dampness is a fault in your vapor barrier. This musty smell will carry through your full property over time, but it will most likely remain concentrated where the damage is worst. As such, if you follow the smell, you should at least narrow down the general area in which your vapor barrier has been compromised. 

Wet or Rotting Crawl Space Insulation 

While crawl space insulation is generally water-resistant, not all types are waterproof and will become saturated if exposed to consistent dampness and humidity. When this insulation becomes wet and saturated, it will start to degrade or even rot. This will contribute to the musty smell in your crawl space as well as harboring mold and mildew and even attracting pests. 

Pest Infestation 

Pest infestation is a very strong sign that you have tears or punctures somewhere in your vapor barrier because there are few other ways in which they could gain entry to your property. Full encapsulation of your property’s crawl space should create a safe bubble of sorts inside your home. If you are finding water, mold, or pests inside this space, it is a definite sign that the vapor barrier itself has been compromised. 

Standing Water 

Standing water is not necessarily a sign that your vapor barrier is damaged; the water could well have come from within your home. If you find standing water inside your crawl space, you must first assess your home to see if there is an internal leak. If you cannot find an internal cause for the presence of the water, it is most likely coming from outside your home. 

As such, standing water of any amount is a sign that your vapor barrier has been compromised, damaged, or is simply past its useful life span. Of course, you will need to drain the water in order to complete a full inspection. As such, it is best to call in a professional.  

Bad Vapor Barrier


Your crawl space is an incredibly vulnerable area within your home. If you do not encapsulate your crawl space or take waterproofing measures, you leave it open to flooding, dampness, and pests. This may seem like an isolated issue, but it will have an effect on your home as a whole. 

A Safe, Clean Crawl Space 

Vapor barriers are rarely (if ever) installed as an isolated or singular protective measure. This is possible, of course, but they are generally part of a wider waterproofing system. When used as a part of an encapsulation system, a good vapor barrier will essentially close your crawl space off from the rest of the world as a whole. 

This makes a neat, tidy, and clean bubble within your crawl space. This bubble should have a dry, comfortable, hygienic climate that improves the overall climate of your property. An encapsulated crawl space will enjoy a more controlled level of humidity and a more stable temperature, which lowers the likelihood of freezing pipes in winter. 

Extra Storage 

As well as creating a clean, protective space under your home that acts as an extra buffer zone between your property and the soil, an encapsulated crawl space can also be a wonderful storage space. Many people who encapsulate their crawl spaces use them to store seasonal decorations and items that are needed only once or twice per year. 

If you intend to do this, you should invest in a very thick and durable vapor barrier of at least 20-mil. This will ensure that the barrier does not tear or puncture when boxes or people move across it. A thinner barrier may need to be regularly replaced if the items you store are too heavy or you drag them across the ground when placing and removing them. 

Dampness and humidity may seem like the very least of a homeowner’s worries, but they are the most insidious of issues. Many avoidable problems and damages within a property can be traced back to persistent, untreated dampness. 

Dampness is Unhealthy 

Persistent dampness in a property, whether it starts in the crawl space or kitchen, is unhealthy for you and your home. One of the most common side effects of humidity and dampness is the formation of mold and mildew. While many species of mold are benign, there are plenty that can cause skin irritation, persistent headaches, and respiratory issues (as well as exacerbating pre-existing conditions). 

Mold, mildew, and humidity can also attract many pests. Cockroaches, for example, can thrive in these conditions and will quickly spread through a property. They will leave germs and droppings everywhere they go and can carry many different germs that will make your home far less hygienic and healthy than it should be. 

Dampness Can Cause Damage 

Humidity and dampness in your property’s crawl space can also cause secondary and tertiary damage throughout your home. As well as the obvious issues of wood rot in exposed beams and floorboards, there are less common and arguably more serious issues that can be caused by persistent dampness in your crawl space. 

Pre-existing cracks in your property’s structure, for example, can be worsened when winter causes the moisture that has gathered in them to freeze and expand. Likewise, if you have exposed pipes in your crawl space, continual dampness and humidity can cause them to rust, corrode, and leak. Eventually, this could lead to the pipes bursting, which will only worsen your issues with dampness. 

We do not recommend that you undertake any repairs or waterproofing tasks alone. It is always better to involve a professional because you will be guaranteed the best possible products, services, and results at every turn. Installing a vapor barrier may seem very simple, but there are many complexities to consider. 

Professionals Will Get the Right Option for You 

Finding the right vapor barrier for your home, the local climate, and your individual needs is not as easy as it sounds. While it might seem as simple as walking down to the local hardware store to get a vapor barrier over the counter and sticking it in your crawl space, it is actually a fairly complicated process, a process that is further complicated by the fact that many hardware stores do not stock professional-grade products. 

A professional will not only have access to the best products, but they will be able to match your needs and budget with the right product for you. This will ensure that you get the results you need at the right price. It will also ensure that you do not need to worry about your vapor barrier once it has been installed; you will simply be able to get on with your life, safe in the knowledge that your crawl space has been taken care of. 

DIY Installation Can Cause Damage 

Attempting a DIY installation can seem like a good idea if you are an enthusiastic amateur, but there is a number of things that could go wrong. Assuming you choose the right product for your home, installing it without causing damage to the barrier can be much harder than it sounds. Even the most durable barrier will tear if it catches on a power tool, after all. 

Likewise, making sure you get a snug, watertight seal at every point is not as easy as the professionals make it look. If you install a vapor barrier that still lets moisture in, you will only have succeeded in creating a hothouse environment that speeds up the germination process for mold, mildew, and pests. 

Expert Installation Guarantees Results 

Contacting a professional crawl space specialist may seem a little over the top, but they are called experts for a reason; they know what they are doing. Hiring an expert to deal with your vapor barrier the first time could save you a lot of money in the long run. As well as being certain you will get professional-grade products, you can be sure they are installed properly. 

A professional is not likely to damage your vapor barrier during installation, and if they do, they will make sure to rectify their mistake. This means you get the right results the first time. As such, you can be sure that the cost of your vapor barrier installation is exactly what you are quoted; a DIY job can see costs climbing quickly as a result of mistakes and miscalculations! 

The Damage a Bad Vapor Barrier Can Do 

Some homeowners may think that a substandard vapor barrier is better than no vapor barrier at all, but this is simply not the case. Rather like poorly fitting crawl space vent covers, an inefficient vapor barrier will only magnify the damage that dampness and pest infestations do by trapping them in. Moisture and pests that make their way into an exposed crawl space will be able to disperse as well as accumulate. 

However, when water enters your crawl space through a tear or puncture in your vapor barrier it has nowhere to go and will simply stagnate inside your crawl space. This can lead to a number of issues including: 

Wood Rot 

Any exposed wood within your crawl space will rot very quickly if water becomes trapped on the inside of the vapor barrier. This will cause wood to crumble, harbor mold, and even attract pests. This could have an effect on your health if it is not addressed quickly. 

Sagging Floorboards 

When wooden beams rot, the flooring they support will start to sag. This could be quite minor at first and present itself as a slight bounciness underfoot. However, if left to escalate, this can result in the flooring separating from the walls and eventually collapsing as a result of lack of support. If the underside of the flooring is exposed, these floorboards can also begin to warp and rot. 

Increased Energy Bills 

If the humidity in your crawl space becomes intense, it could have a serious impact on your energy usage. This will impact your energy bills. However, it could also lead to avoidable breakdowns in your HVAC system as it struggles to heat or cool the humid air. 

Of course, these are just some of the issues that can be raised by having a poorly fitting or damaged vapor barrier in place. As such, it is far better to have it repaired or replaced as quickly as possible. We recommend that you call a professional to do this for you. This will guarantee you the best possible results.  

Choose Complete Basement Systems for Crawl Space Repair 

Complete Basement Systems is the premier crawl space repair and encapsulation contractor in and around Denver and Colorado Springs, CO. As specialists who are local to this area, we understand the sometimes harsh contrasts of the Colorado climate and have built a portfolio of products designed to withstand them. Our vapor barriers are no different, and with our team to back up this excellent product, we feel confident in our position as the region’s leading crawl space specialists. 

Our vapor barriers are: 

  • Easy to install 
  • Durable 
  • Mold Resistant 
  • Warrantied for your protection  

So, if you have noticed signs of dampness, humidity, and general ineffectiveness or damage to your vapor barrier, give us a call. Our team will be happy to help you restore your home to full health. Alternatively, you can arrange a free inspection online. Our inspectors will let you choose a date that works best for you and perform a thorough assessment of your home. These inspections are free and come with no obligation to book repairs through us. 

We believe that our work speaks for itself and that you deserve a chance to shop and around. Peace of mind is everything when it comes to your home. This is why we provide a same-day written estimate with each inspection. You can take all the time you need to make a choice, of course, but if the situation in your home deteriorates quickly, please do feel free to call us for emergency assistance; your safety is important to us. 

Serving Greater Denver area, Colorado Springs, Eastern Colorado, and parts of Nebraska and Wyoming

Colorado Springs, CO

707 County Line Rd.
Palmer Lake, CO 80133

Denver, CO

4686 Ivy St
Denver, CO 80216