Why Your New Home's Crawl Space Already Has Fungus: A Builder-Grade Warning

Introduction

Common Issues We See on New Builds

CRAWL SPACE ENCAPSULATION MISHAPS FROM CUTTING CORNERS

I just inspected a two-year-old home in Lebanon that really got me fired up.


The house is beautiful, the crawl space looks professionally done at first glance - spray foam, poly barrier, the works.


But there's already fungus growing everywhere.


Why?


Because the builder skipped one critical thing: dehumidifiers.


This happens more often than you'd think.


New homeowners assume everything's fine because, well, the house is new.


But I'm finding these problems in new homes all across Middle Tennessee, and it's usually because of the same corner-cutting approaches.

(615) 265-0081
  • A basement filled with plastic and pipes.

The Builder-Grade Problem

Let me tell you what "builder-grade" really means. It means doing the minimum required by code, not what's actually needed for your home. In this Lebanon house, the builder probably saved a few thousand dollars by skipping the dehumidifiers. They weren't required by code, so they weren't installed.


Here's what typically happens:

  • Builder hires the cheapest crawl space company
  • Company does only what code requires
  • Important but "optional" items get skipped
  • Homeowner inherits the problem


The spray foam and poly barrier looked great - I'll give them that. But in Middle Tennessee's humidity, that's like building a boat without a bilge pump. It might look good, but it's not going to keep you dry for long.

  • The ceiling of a basement with a lot of pipes and insulation.

  • A basement with a lot of insulation and a light on the ceiling.

  • A basement with a lot of pipes and columns

  • An empty basement with a wooden ceiling and white walls.

The Real Cost of "Savings"

Here's the thing about builder-grade savings - they become the homeowner's expensive problems. In this Lebanon home, the builder probably saved $3,000-4,000 by skipping proper dehumidification. Sounds good for them, right?


But now, just two years later, the homeowner needs:

  • Complete fungus remediation
  • Two dehumidifiers (because of the crawl space layout)
  • Professional installation
  • Thorough cleanup


That "savings" just turned into a much bigger bill for the homeowner. And the worst part? All of this could have been prevented.

What Was Missing

At first glance, this crawl space looked fine. The spray foam was done well, and the poly barrier seemed okay. But without dehumidifiers, it's like having a rain jacket with no hood - you're still going to get wet.

The problem got worse because of how this crawl space is laid out. There's large ductwork running through the middle, basically creating two separate spaces. Now they need two dehumidifiers instead of one, and getting them installed is trickier because of the layout.

  • A man is working in a basement under construction.

How to Protect Yourself

If you're buying a new home or having one built, here's what you need to ask about:

  • What kind of moisture control is included?
  • Are dehumidifiers part of the system?
  • How many do you need for your space?
  • Who's responsible for the equipment after closing?


Don't let anyone tell you dehumidifiers are "optional" in Middle Tennessee.


Between our humidity and changing seasons, proper moisture control isn't a luxury - it's a necessity.

  • The ceiling of a basement with a lot of pipes and insulation.

  • A basement with a lot of insulation and a light on the ceiling.

  • A basement with a lot of pipes and columns

  • An empty basement with a wooden ceiling and white walls.

The Right Way

Let me tell you how this should have been done from the start.


A proper crawl space system in Middle Tennessee needs:

  • Quality encapsulation (which they did have)
  • The right number of dehumidifiers for your space
  • Proper placement of equipment
  • Regular monitoring capability


In this Lebanon home, we need two units because of that ductwork division. Each section needs its own moisture control. That's just how it is - trying to cut corners here will just lead to problems down the road.

Next Steps

If you've got a new home, don't wait for problems to show up.


Here's what you should do:

  • Check your crawl space for musty smells
  • Look for any signs of moisture
  • Find out if you have dehumidifiers
  • Get a professional inspection if you're unsure


The sooner you catch these issues, the easier and cheaper they are to fix.


Two years of fungus growth means more work and more expense than catching it early.

Crawl Logic

Ready to Get Your Crawl Space Checked?

I inspect crawl spaces all across Middle Tennessee, and I'll tell you straight if there's a problem or not.


The inspection is free, and you'll get honest answers about what your home needs - no scare tactics, no unnecessary work.


Give me a call or text. Unless it's a major holiday, I'll get back to you quickly. Let's make sure your new home stays protected from the ground up.

(615) 265-0081
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