In Middle Tennessee, crawlspaces experience dramatic seasonal changes, especially when it comes to humidity. If you’re buying an older home in Nashville, Franklin, or anywhere across the region, understanding what happens under the house is critical to protecting your investment.

Two Seasons, Two Different Crawlspaces

When it comes to crawlspaces in the humid South, it’s almost like you’re dealing with two entirely different environments depending on the time of year.

• In winter, fall, and early spring, crawlspaces tend to stay dry and cool. There’s less moisture in the air, and humidity levels are naturally lower. It’s easy to assume everything is fine under your house during this time.

• In the summer, however, it’s a completely different story. As heat and humidity rise, crawlspaces can turn into a moisture-filled jungle. Metal pipes and ducts start to sweat, condensation builds up, and mold finds the perfect breeding ground.

This constant cycle of dry-to-damp seasons takes a toll on home, especially those with older, vented crawlspaces.

Why Crawlspace Moisture is a Big Deal in Tennessee

Moisture is one of the top enemies of a healthy home in Middle Tennessee. When your crawlspace isn’t sealed or managed properly, you may experience:

• Wood rot and structural damage
• Mold growth can affect indoor air quality
• Pest infestations (they love damp, dark places)
• Sagging floors and musty odors
• Higher energy bills due to insulation degradation

Middle Tennessee homes often deal with three moisture sources:

• Rainwater from above

• Groundwater from below

• High humidity in the air

This triple threat makes crawlspace maintenance not just a recommendation, but a necessity.

Should You Open or Close Crawlspace Vents?

One common question from homeowners: “Should I open or close my crawlspace vents depending on the season?”

Here’s the simple advice:

• Open vents in summer, when humidity is highest, to help move air through the space.

• Close vents in winter, when the air is drier and cold drafts can cause plumbing issues or increase energy use.

BUT, here’s the catch: ventilation alone won’t solve your crawlspace moisture problems. While airflow helps, it doesn’t eliminate condensation or groundwater intrusion. If you’re seeing signs of mold, wood rot, or high humidity, it’s time to consider a more permanent solution like encapsulation or a vapor barrier upgrade.

Buying an Older Home? Don’t Skip the Crawlspace.

In a hot real estate market like Nashville’s, it’s easy to fall in love with a home’s hardwood floors, white cabinets, and fresh paint. But what’s happening underneath the house can quickly turn into a deal-breaker.

When purchasing a home in Middle Tennessee, especially one with a vented crawlspace, make sure your home inspector does a thorough crawlspace evaluation. If moisture is present, ask about options like:

• Vapor barrier replacement

• Crawlspace encapsulation

• Sump pumps or drainage systems

• Mold remediation

The DILIGENT Difference

At DILIGENT, we inspect thousands of crawlspaces across Nashville, Murfreesboro, Franklin, and the surrounding region every year. We know exactly what to look for, from subtle signs of high humidity to obvious water intrusion.

Live in Middle Tennessee? Buying a home with a crawlspace?
Schedule your home inspection with DILIGENT and get real answers about what’s happening under your future home.