Closed Crawl Space (Update) – Pest Management Systems Inc.
Learn More About Your Potential Career at PMI   

View Opportunities [x]

Closed Crawl Space Services


The crawl space is an area of the home that isn’t thought about very often.  In most cases it one of the few places that a homeowner has never seen.   Don’t be fooled though, a crawl space is an important part of the home and when its environment gets out of control, the effects can be felt throughout the house.

Not only can high humidity in your living space can cause problems, but the same is true in your crawl space.  In this type of environment many things can thrive such as mold, insects and rodents.  It can lead to wood decay, musty odors, and poor indoor air quality.  Excessive moisture on the underside of your floor system can even cause hardwood floors to start cupping due to expansion of the wood occurring on that one side.



We don’t think too much of the water that forms on the outside of a cold glass.  That water comes from condensation which occurs when the surface temperature of an object is lower than the dewpoint.  This can also occur in the crawl space, but instead of it harmlessly forming on your drinking glass, it can form on your wooden floor joists, HVAC ducts, water pipes and just about any other surface.  Condensation is a major factor to many of the crawl space problems we see.

Our CrawlSpace Care system is installed to reduce humidity levels which in turn drastically lowers the dew point to levels in which condensation cannot occur.  This is a major win for your crawl space!


One of the biggest concerns among our customers is mold and fungal activity which can be found in a lot of crawl spaces.  For these to grow, they need water, food, and oxygen.  We cannot control the oxygen in the air or the food they eat (virtually any organic carbon-containing matter), but the water is something that can be controlled.  With high levels of humidity and especially condensation, mold can thrive.  The good news is that you don’t have to remove all the moisture in the air to avoid mold and fungal growth.  Eliminating water entry (standing water) and reducing relative humidity and can take away the ingredients needed for mold growth.   

If mold or fungal growth is already present in the crawl space it is always best to remove or treat it.  Even a dead mold spore has potential health concerns.


Wood Rot is a form of decay fungi that is triggered by high moisture in the wood.  This can lead to structural damage and in severe cases collapse.  An encapsulated crawl space can reduce crawl space moisture and keep wood moisture content at appropriate levels to avoid this costly condition.


A crawl space is a likely source if you are experiencing any musty odors in your home.  Mold and/or mildew can create this unpleasant odor which can permeate through small openings and penetrations in the floor system and make its way into the living area.  The best way to eliminate the odor is at the source.  To keep it from coming back it is most important to keep the humidity under control so that it can’t be produced again.


You may not think of the crawl space if you notice your hardwood floorboards are starting to cup, but it likely can be the source of the problem.  Water and moisture can cause things to expand.  When the underside of a hardwood floor is exposed to high humidity that side of the board will start to expand.  On the top side (your living space), humidity is usually well controlled with air conditioning.  This imbalance will cause the bottom of the wood to expand, but not the top.  If caught early, correcting the moisture problems in the crawl space will sometimes allow the wood to shrink back to normal and reverse the cupping.


Humid conditions in the crawl space can lead to higher humidity levels in the living space.  This can be uncomfortable making it feel sticky, hot and damp.

Pest Management - Closed Crawl Space Insects in Crawlspace


PMi has years of experience identifying these problems.  We start by performing a thorough inspection of the crawl space, take various measurements (relative humidity, dewpoint, surface temperature, wood moisture content, and air temperature), and document other areas of concern so that we can present you with the facts.  Only then can we provide you with a recommendation on how we can help correct any problems.


It’s important to also choose the right company like PMi who prides itself on quality and customer satisfaction.  We also stand apart as we can not only able to take care of the moisture, but we can help protect against pests at the same time as your licensed pest control provider.

They are professional, courteous and exceptional at what they do. Our crawlspace is now clean and dry and will ensure our home and our family will be safe with better air quality for many years to come.

Catherine Arnold, Verified Google Review

Our Premier Closed Crawl Space Solution

In many cases, a closed (also known as unvented or encapsulated) crawl space is the best solution.  One of the biggest factors of why crawl spaces are failing is because the crawl space is using foundations vents as a means for moisture control.  Recent studies now show why that is not an effective solution. Learn more about Vented vs. Unvented Crawl Spaces.

PMi’s CrawlSpace Care system is designed to take your crawl space to the next level and transform it into an effective and efficient closed crawl space.  Every home is different and depending on its current conditions will require a custom set of solutions.  In some cases, other contributing and consequential factors may need to be addressed first such as drainage, fungal remediation, and debris removal.

    The CrawlSpace Care* system addresses the moisture issues by sealing the foundation vents, sealing air penetrations in the foundation and floor system, installing a high-quality reinforced floor liner, wrapping the piers, sealing the seams, installing mechanical drying and various other techniques.  Many times the floor insulation is no longer effective (saturated, sagging) and must be removed.  We then install a termite resistant rigid foam insulation on the interior of the foundation walls.  

    In the end your crawl space, will be cleaner, brighter, and most importantly perform better than before.

    *The CrawlSpace Care system is the sum of many different components, products and services.
    The quick summary above is a description of a typical installation.  Every home has different requirements
    which may alter the scope of what is proposed and installed.  This will be detailed in the proposal.



      One of the most important benefits of a closed crawl space is the reduction in moisture levels.  High levels of moisture is one of the biggest contributing factors to mold, wood rot, pest activity and musty odors


      A large portion of the bad air you breathe in the living space originates from the crawl space.  When bathroom fans, dryers and other ventilation systems are running air is being removed from the home.  That air being removed must be made up from somewhere.  Penetrations in the floor system for plumbing, HVAC, cable and electrical are pathways for air to be pulled in.  

      This condition also occurs with the Stack Effect.  Warm air rises in structures causing a reduction of pressure in the lower areas.  This will draw in air from the outside and even the crawl space.  When there are moisture problems present in the crawl space this moist, musty and unhealthy air can be brought up into the living areas.

      After the installation of CrawlSpace Care, many accessible floor penetrations are sealed but most importantly, the overall environment in the crawl space is drastically improved.


      Not only does a closed crawl space reduce moisture, but it helps you save on the energy to heat and cool your home.  That’s right, studies performed right here in North Carolina (and elsewhere too) which were funded by the US Department of Energy resulted in showing that a closed crawl space saved up to 18% on the heating and cooling costs when compared to a traditional vented crawl space.  Learn more about this study here.


      Insects thrive in environments with high humidity. This is why a lot of pest activity can be found in most crawl spaces. With the installation of CrawlSpace Care, the reduction of humidity leaves pests with a crawl space that is less inviting and may leave them looking elsewhere for that perfect place to call home. Additionally during the installation, most penetrations in the foundation and floor system are sealed which helps to keep pests out of the living space.

      Frequently Asked Questions

      PMi is the premier Pest and Moisture Prevention company for Greensboro and the greater North Central region of NC. Our mission is to provide expert solutions to safeguard your property from pests and excessive crawl space moisture while being responsible stewards of public health and the environment. Our team of experts has curated these FAQs to help you better understand the impact of how crawl space moisture issues can be conducive to insect activity, mold, odors, wood damage, and even damage to the foundation of your property.

      We hope this valuable information empowers you to make informed pest management and moisture prevention decisions. If you don’t find the answer to your question here, don’t hesitate to contact our knowledgeable team. We’re here to assist you with practical solutions tailored to your specific needs.

      How can excessive moisture in my crawl space lead to pest activity?

      Moisture can and will attract insects, as many pests are attracted to damp and humid environments in which they need to live. Certain insects, like termites and cockroaches, thrive in moisture-rich conditions. Controlling moisture levels is a crucial component of integrated pest management.

      How is moisture in my home related to mold/fungi?

      Excess moisture creates a perfect breeding ground for mold and fungi. These microorganisms can grow on various surfaces and release spores that may cause health issues. When mold and fungi grow on the wooden components of your home, this can lead to structural damage over time. It’s essential to address moisture problems promptly to prevent mold and fungi growth.

      How can moisture contribute to unpleasant odors in my home?

      Damp environments foster the growth of bacteria and mold, producing musty and foul odors. Insects, rodents, and wild animals attracted to the wet environment can also produce undesirable odors. Proper crawl space moisture prevention can help prevent these unwanted smells by eliminating the sources of those odors.

      What can excess moisture do to my wood floors?

      Moisture can cause wood floors to deform. When wood absorbs excess moisture, it swells, leading to buckling, warping, and cupping of floorboards. This not only makes the appearance of floors unsightly but can also lead to tripping hazards. Managing crawl space humidity levels is vital to preserving the integrity of your wood floors.

      How does excessive water and moisture put the foundation of my home at risk?

      Drainage issues around the foundation of your home can cause the wet soil to expand and contract. This can place excessive stress on various parts of the foundation, leading to cracks and settlement issues. When issues like this are left unaddressed, the home can become unsafe to inhabit due to the possibility of structural failure. Maintaining proper drainage and moisture control is essential to protect your foundation.

      How does crawl space mold/fungal remediation work? How long till the mold and fungus are gone?

      Mold and fungal remediation involves identifying the source of moisture that fosters mold growth and addressing it, along with eliminating the existing mold and fungus. The duration of the process varies based on the extent of the moisture, mold, and fungus proliferation and the size of the affected area. Our experts at PMi use effective techniques to eliminate the mold and fungus and, more importantly, to ensure that it doesn’t come back.

      Why do I need a closed crawl space when I’ve always been told the crawl space needs to breathe?

      The idea of a “breathing” crawl space is outdated. Modern air conditioning systems result in extreme temperature differences between the home’s living and crawl spaces. This effectively makes the wood surfaces in your crawl space act like the outside surface of a glass of ice water in the summer. Condensation forms on the wood in your crawl space, leading to many other issues over time. Closed crawl space systems are more effective at controlling moisture, creating conditions less conducive to pest activity, and improving indoor air quality. When PMi professionally seals your crawl space, it becomes a clean and controlled environment that helps maintain optimal humidity levels and prevents structural and pest issues. It makes your home more energy efficient, too!

      Why put rigid foam/wall insulation in instead of subfloor insulation?

      Rigid foam insulation, or insulation placed on the interior of the exterior walls of the crawlspace, is more efficient in preventing heat loss and cold air intrusion. It helps maintain more consistent temperatures within the crawlspace, which, along with reduced humidity from the closed crawl space system, helps prevent condensation on the subfloor.

      Doesn’t the vapor barrier stop all moisture problems?

      While vapor barriers are essential for moisture prevention, they may not solve all moisture issues alone. A properly closed crawl space uses a comprehensive approach, including drainage, air sealing, mechanical drying, and monitoring to manage moisture problems effectively.

      If you have any more questions or need expert pest and crawl space moisture prevention solutions, feel free to reach out to PMi! 



      Request below. An expert will contact you to schedule at your earliest convenience.

      "*" indicates required fields

      This field is for validation purposes and should be left unchanged.
      Request Quote

        Close Popup
        Request an Appointment
        Close Popup