Skip to Main Content

Why Crawl Space Moisture Is Worse in the Summer

moist crawl space with ruined vapor barrier and sagging insulation

When temperatures soar in the Sunshine State, and summer storms bring increased humidity, our homes face a unique set of challenges. Some of these problems arise in the crawl space tucked away beneath our feet.

Maybe you’ve been wondering, “Should I be concerned about crawl space summer heat or moisture?”

The simple answer is, yes; these are concerning issues. But worry not; Alpha Foundations has more than 20 years of local knowledge and service to help guide you through it all.

While this may sound daunting, knowledge is power, and with the right information and crawl space encapsulation solutions, crawl space pitfalls can be easily avoided.

How Summer Heat and Moisture Get Into Your Crawl Space

Most crawl spaces are incredibly efficient at supporting the weight of your home. But one thing they aren’t very good at is keeping moisture out, and it all goes back to an outdated construction code—open crawl space vents. Understanding this root cause of crawl space issues is the first step towards finding effective solutions.

protruding crawl space vent

Traditionally, crawl space vents were installed with the idea that they would promote air circulation, helping to keep the crawl space dry. However, in reality, this doesn’t work as intended, and it only exasperated, especially during Florida’s hot and humid summers. When the outdoor air is heavy with humidity, these vents serve as open gateways for moist air to flow directly into the crawl space.

This has two major effects in your crawl space. First, when the hot, humid air meets the cooler surfaces in your crawl space, it can cause condensation. Second, this moisture-laden air itself raises the humidity levels in your crawl space. Both scenarios create a damp environment that fosters mold growth, wood rot, and other crawl space problems.

Likewise, the open vents also allow the summer heat to penetrate your crawl space, raising its temperature. This warming effect can make your home’s floors uncomfortably hot and force your air conditioning system to work harder, driving up your energy bills.

In a nutshell, open crawl space vents are actually the cause of excessive heat and moisture in your crawl space. It might seem counterintuitive, but closing these vents is a crucial first step toward improving the conditions of your crawl space. This benefits your crawl space not just during the summer months, but all year-round.

Common Crawl Space Problems in the Summer 

The dog days of summer in Florida aren’t just about beach trips and barbecues; they bring along a set of challenges for the crawl space under your home. Here’s a look at some of the most common issues homeowners in our sunny state often face during these hotter months. 

High Humidity Levels

measuring crawl space humidity levels

With summer comes the regular afternoon showers and a surge in humidity, which will easily seep into your crawl space if not properly sealed. This heightened humidity can lead to a damp crawl space environment. Dampness can then promote mold growth, which may eventually lead to unpleasant odors and poor indoor air quality. It can also contribute to pest infestations from critters like termites that thrive in moist conditions and can cause substantial structural damage.


Florida’s high summer humidity leads to condensation in your crawl space, a process that occurs when warm, moist air meets cooler surfaces and releases water droplets. Condensation may initially seem harmless, but in reality, it creates an environment that promotes moisture issues.

The accumulation of water droplets dampens wooden structures, which over time, leads to wood rot. Wood rot compromises the structural integrity of your home by weakening the wooden beams and joists supporting your floors and walls. You may be left with sagging floors as a result. Additionally, condensation causes rust on metal structures, like water pipes, leading to potential plumbing issues and costly repairs.

Mold and Poor Air Quality

When considering the air quality in your home, the crawl space plays a direct role. This often-neglected area often hosts mold spores, dust mites, and other allergens, especially when humidity levels rise in the summer. These airborne particles can easily infiltrate your living space through cracks, vents, and even your home’s HVAC system, directly impacting your indoor air quality. The result is an environment that may exacerbate allergies, trigger asthma attacks, or cause other respiratory issues.

However, the issue isn’t just limited to allergens. The humid, damp conditions of a crawl space can also facilitate the growth of bacteria and fungi, further polluting the air you breathe indoors. Excess moisture might also lead to a musty odor emanating from your crawl space, which could make your home less pleasant. Thus, maintaining a dry and well-ventilated crawl space isn’t just a matter of home maintenance but also a vital step toward ensuring a healthier living environment for you and your family.

mold growing on wooden crawl space joist

How to Protect Your Crawl Space in the Summer

Keeping moisture out of your crawl space requires water management tools. The most effective way to do this is with a process known as crawl space encapsulation. You may have heard of this before! Encapsulation has become more popular today because many homes are only just starting to feel the negative effects brought on by an old crawl space.

Crawl space encapsulation combines multiple waterproofing solutions to create one large water management system below your home. This process creates a dry, controlled environment below your home. Not to mention, it gives your crawl space a facelift. You can see an example of a crawl space benefitting from encapsulation to the left.

Crawl Space Encapsulation from Alpha Foundations

encapsulated crawl space with wooden ceiling

At Alpha Foundations, we have industry-leading tools at our disposal. For more than 20 years, we’ve provided Florida homeowners with an outstanding crawl space encapsulation system designed to remove water quickly and keep it out for good.

With crawl space encapsulation, our team transforms your crawl space into a controlled environment impervious to water intrusion. Without moisture below your home, the support beams supporting your floors won’t succumb to wood rot, and your home’s air quality will stay safe from mold and pests.

We use the following waterproofing measures below your home:

Keep Your Crawl Space Cool With Alpha’s Local Expertise and Service!

Alpha crew carrying crawl space drainage matting

If the summer heat and humidity are making your home suffer, consider working with Alpha Foundations. We take a customer-first approach to crawl space maintenance. Our comprehensive services include assessing existing damage, recommending appropriate solutions, and providing regular maintenance to ensure the longevity of your home’s crawl space.

With our deep understanding of Florida’s unique environmental conditions and our commitment to exceptional service, we’re equipped to help you protect your home from the ground up. Contact us today for a free inspection; we provide the solutions you need to maintain a dry, healthy, and energy-efficient home, no matter what the Florida weather brings!

Ted Dryce

Ted Dryce

Content Writer

Ted is an SEO Content Writer who has been with Groundworks since 2021. He’s covered home repair topics ranging from crawl space encapsulation to regional soil conditions. When he’s not working, Ted is performing improv comedy and working on his own creative projects.

Publish Date:

Last Modified Date:

Alpha Foundations Service Areas

Our Locations

Fort Myers

1755 Benchmark Ave.
Fort Myers, FL 33905


309 NE 1st St.
Gainesville, FL 32601


55 North Industrial Loop
Orange Park, FL 32073


3200 W Copans Rd.
Pompano Beach, FL 33069


3723 Hogshead Rd
Apopka, FL 32703


1680 Fruitville Rd.
Ste. 516
Sarasota, FL 34236


66 Industrial Park Dr.
Monticello, FL 32344


1615 118th Ave. N
St. Petersburg, FL  33716


100 N Patterson St.
Valdosta, GA 31601

West Palm Beach

515 N Flagler Dr.
Ste. P-300
West Palm Beach, FL 33401