Optimizing Crawl Space Encapsulation: The Role of Dehumidifiers

Nick Luzak


Imagine this scenario: it’s a scorching 95 degrees in mid-July here in Delaware, with the humidity making it feel like 105 degrees. The outside weather is downright unbearable! In such situations, we all want our homes to provide a cool and comfortable refuge, don’t we? Now, would it make sense to crank up the air conditioning and open all the windows? Unfortunately, doing so would cause the air conditioning unit to work tirelessly, struggling to combat the hot and humid air infiltrating the house. Similarly, installing a dehumidifier in an unsealed or vented crawl space would yield the same ineffective results. It would be as futile as attempting to eliminate the humidity from your entire neighborhood by placing the dehumidifier outdoors.

Believe it or not, we have come across numerous crawl spaces during our inspections that have open foundation vents and dehumidifiers installed. In some cases, homeowners were convinced by contractors to invest in a dehumidifier as a solution to their moisture problems. However, this approach only results in wasted money, a defunct piece of equipment, and the persistence of the original issues they sought to address.

While humidity may not pose as significant a problem during the winter months, it’s worth noting that dehumidifiers have low operating temperature limits. If they need to operate and the crawl space is filled with frigid air due to open foundation vents, they will frequently enter defrost mode. This constant defrosting can negatively impact the lifespan of the dehumidifier.

Here’s the key: crawl space encapsulation aims to seal the area completely, and brings the crawl space into the thermal boundary of your home, preventing any moisture-related issues. Achieving a high level of encapsulation and effective air sealing significantly enhances the efficiency of the dehumidifier in maintaining optimal humidity levels within the space.

Once the crawl space encapsulation process is complete, the inclusion of a dehumidifier becomes crucial for maintaining a healthy and dry environment. It is imperative to equip every sealed crawl space with a dehumidifier to prevent the accumulation of moisture. Neglecting to do so may result in additional problems rather than resolving them.