Structure: Basement/Crawlspaces

The nastiest place in your home may surprise you

Crawlspace, the filthiest place in your home
Where is all my heat going? And what is that smell??
Crawlspace, the filthiest place in your home
How many problems can you spot? Let me know??

Beware… an invisible, unhealthy area of your home may be making you sick.

Where is the nastiest place in your home? Behind the refrigerator? Under the washing machine? Around the toilet? Nope. The nastiest place in your home is a place you may not even be aware of… and it’s right under your feet.

If you want a good a scare, check your crawlspace.

Under your floor is the crawlspace, an area rife with dust, disease and crawly creatures. Some are alive… and some not so much. This small dark world may be out of sight, but its toxic environment permeates your every breath, and affects the health of the entire structure…even in the most beautiful and expensive homes. the crawlspace is truly the filthiest place in your home.

What’s a crawlspace

Crawlspaces are shallow, uninhabitable areas located between the soil and the first floor of the home. They are typically excavated below grade and are meant to provide ventilation and access to the foundation, framing, and utility systems running below the floor. This area is avoided by everyone except brave plumbers and termite inspectors and who can blame them? These areas are dark, barely accessible and dangerous. They are also the filthiest place in your home.

Out of sight, out of mind

After just a few years of neglect, crawl areas can become universally unhealthy and dangerous places for humans. Even for pros equipped with protective gear, descending into a crawlspace abyss is no picnic. Inspectors daring to go into the crawlspace, are regularly confronted with abandoned construction debris, mold, termites, spiders, wood rot, plumbing leaks, mud, standing water, raw sewage, sharp nails, empty beer cans, reptiles and both living and deceased rodents. One large luxury home HPS worked on had 37 rodent carcasses under the home. That must have been nice to live with.

Dreadful air quality makes for the nastiest place in your home

Homeowners would be absolutely appalled if they could see the conditions just inches under their feet. Here’s the really bad part. Even though you don’t see it, the crawlspace is affecting you. The reason for this is that air from the crawlspace permeates into your home and mixes with the air you breathe. It gets in through leaky heating ducts, around oversized holes cut for plumbing and electrical lines and through minute cracks or other openings in the subfloor.

Water in the crawlspace

The filthiest place in your home
How to dress for a crawlspace visit

The dirt floor of the crawlspace is below grade, so any drainage issues from outside will allow water to find its way in.  Moisture in your crawlspace means a big “F” on your home’s drainage report card. You may have a problem with overflowing gutters, disconnected downspouts, poorly sloped splash blocks, bad perimeter grades, failed perimeter foundation drains, broken water lines or all of the above. You may also have a home that was built over a spring or is subject to runoff water from neighbors.

In really serious cases, crawlspaces can have several inches of standing water collected in them. Any water in the crawlspace can cause mold, mildew and elevated humidity problems in the house. All of these problems contribute to poor air quality. Moist soil and standing water will also soften the foundation footings and allow settlement and eventual foundation damage to occur.

A wet crawlspace screams that something is wrong, so the first thing you should do is figure it out and fix it. You may need some professional help with tracking this down. Learn more about perimeter drainage systems and how they work by visiting my foundation and drain pages.  Eliminating moisture makes crawlspace clean-up and repair much easier.  

Fight back

The good news is that bad crawlspaces can be fixed. A bit of clean-up and the repair of broken ducts and drainage problems will make a huge difference. There are professionals out there who will even do this for you.  Because the work is dirty, dangerous and must be done in dark, cramped conditions it is not inexpensive. Call and get several proposals.  

If you are brave, you might consider doing the clean up job yourself. It won’t be easy or fun but it will be worth the effort.

Here’s a plan:

Keep safety in mind first. Wear protective gear and make sure you arrange good lighting and fresh air.  Make sure the access hole is large enough to get in and out safely.  If you are claustrophobic, let someone else do this work. Crawl the entire area making observations and taking. Photos will shorten your time under the home and allow you to review them at length later so that you can make a plan of attack.  

Once you have created a strategy of attack, you can get on with cleaning up the filthiest place in your home.

The filthiest place in your home
A relatively clean crawlspace (uninsulated) w/no liner

The filthiest place in your home clean up checklist

  • Bring in fans to dry out any moisture and provide fresh air.
  • Repair or replace any damaged ducting and strap it properly up to the floor joists.
  • If insulation is in place, check around the plumbing and ducts to see if there are any openings through the subfloor.
  • Secure and reinstall any loose insulation.
  • If there are hanging wires, have an electrician check them out, make them safe and secure them to the framing.
  • Have a plumber check out the system and to secure any loose plumbing and water lines.
  • Seal any and all holes in the subfloor. The idea is to stop air migration between the crawlspace and the living area. Areas that typically have problems are bathtubs, heat ducts, air vents, wire and pipe penetrations.
  • Close any holes in screens or other perimeter openings that might allow rodents to enter. Check the foundation vents and be sure they are sufficient to meet the ventilation code.
Crawlspace liner
Crawlspace after clean up and liner


If your home stinks or smells musty all the time, something is likely wrong in the the crawlspace, the filthiest place in your home. Have a professional check it out and take photos. Most termite companies will do this for you. Don’t hesitate to clean up any messes found in your crawlspace. With a little work you can turn the nastiest place in your home into a surprisingly clean area that will help breath some fresh air into your life.

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