Written By: Peyton Thomas, ESG Environmental Investigator Your crawl space is one of the most important areas to monitor in order to maintain a well-functioning, healthy home. It is also one of the most frequently neglected areas and can be the source of many issues that can affect your living space. Some common issues that arise include strange odors, increased heating/cooling costs, mold and moisture damage, and even pest problems. Something as simple as having a trained indoor environmental professional perform an annual crawl space investigation can potentially save a homeowner hundred or even thousands of dollars in remediation cost and can drastically improve the indoor air quality and comfort within the home. The single most important variable in maintaining a clean and healthy crawl space is proper control of moisture. There are 3 main sources of moisture that can affect a crawl space: external, internal, and excess humidity. Common external sources of moisture include rainwater impacting the crawl space due to improperly maintained gutters and downspouts, rain blowing in through foundation vents, and groundwater intrusion. It is extremely important to keep an eye out for these sources of moisture and staying on tope of them is as easy as a routine walk around the perimeter of the home. Internal sources of crawl space moisture issues can be a bit more difficult to spot and include plumbing leaks, lack of a proper vapor barrier, and faulty HVAC equipment. Excess humidity in a crawl space can be tough to deal with, particularly in a traditional vented crawl space that is exposed to the elements during humid summer months. The ideal way to address the humidity issue is to create a sealed and conditioned crawl space. This method has become quite common among modern custom-built homes where energy-efficiency and performance are primary concerns. However, due to the lower cost of installing a traditional vented crawl space, the majority of newly constructed homes do not have conditioned crawl spaces. A sealed, conditioned crawl space is essentially the same as a conditioned basement. There are no crawl space vents to the outdoors, the soil surface is completely sealed, and the air within is mechanically dehumidified by either tapping into the HVAC system or installing a standalone dehumidifier. Great care is taken to seal all gaps in the subfloor and foundation and the entire foundation wall is insulated to create an efficient, dry and properly functioning space. If you don’t plan to create a conditional crawl space, you should make sure that you have a proper vapor barrier of at least 6-mil plastic sheeting. Preferably, this vapor barrier should extend up the foundation wall and be sealed to create a barrier that is air tight. This will help to reduce soil moisture and odors from affecting the crawl space and living space of the home. It is possible to convert a traditional vented crawl space into a modern sealed, conditioned crawl space but it should not be considered a do-it-yourself job. If building codes and engineering principles are overlooked, sealing your traditional crawl space yourself can be a recipe for disaster due to inadequate dehumidification or other variables. An experienced contractor should always be consulted prior to retrofitting any vented crawl space. So how do you determine if you actually have a moisture issue in your crawl space that needs to be addressed? The only reliable way is to actually go into your crawl space and perform a thorough investigation of the foundation wall, vapor barrier, floor system, and moisture conditions. Things to look for include mold, standing water, drooping insulation, and large amount of pests. The easiest way to identify issues in your crawl space is to contact a professional, like on of the Indoor Environmental Quality professionals at ESG, to perform and assessment of the conditions beneath your home. Our certified professionals are experts at identifying tough to find moisture issues by using calibrated moisture meters, microbiology samplings, and eyes with years of experience. Don’t ignore on of the most important parts of your biggest investment. Contact us to schedule your crawl space check up today!