Crawl Space

What it is

A crawl space is the shallow area between the ground and the first floor. Usually two to four feet tall, accessed through a small door or hatch. It holds the floor system — joists, beam, subfloor — plumbing runs, HVAC ductwork, sometimes the electrical service. You’re not meant to live there, but a lot of expensive problems do.

Always look for extra moisture around the house and in the crawl space. If something’s not explainable, start asking questions. That’s true for anything on a house, but especially the crawl space because it’s where homeowners think nobody will ever look.

I’ve had ductwork pulled down in the crawl space. I’ve had a two-foot piece of copper line going to an HVAC system cut out — I don’t know why you’d cut out two feet. I’ve had situations where the inspection looked clean on a house until we actually got in there and found things that were clearly wrong. The crawl space is where pro diy work hides.

Why it matters

Look for standing water or saturated soil. That’s active water intrusion. Ongoing water damage isn’t covered by insurance, it compounds, and it eats floor systems.

Look for pest evidence. Mud tubes on piers — termites. Fine sawdust — powderpost beetles. Hollow-sounding beams — termites or carpenter ants. I’ve had to take out entire floor systems because of wood-destroying insects. None of this is covered by insurance. All of it gets worse over time.

Look for structural deterioration. Sagging joists, rotted beam sections, cracked piers. I’ve bought houses with foundation issues from being built on unstable or loose soil. They come in and build all these homes at the same time, disturb the land, sometimes the compaction fails, and you find voids in the dirt underneath. That leads to foundation failure.

Water intrusion is the main story in a crawl space. I bought a house on a hill thinking it was going to have a phenomenal view, and I could never stop the water from getting into the basement. I did retaining walls, French drains, curbs, even sealed the foundation. None of it worked. I didn’t understand that the hill was working like a sponge, and water was running through it almost like a stream underground. There’s nothing you can do to stop that. I had to cut a floor drain into the basement so the water that was coming in could get out. Point is: look for clues. Look for any water that could be coming at the house. If it sits next to the house, it gets in.

How it shows up

Any home inspector should check the crawl space, but nobody is going to care about your investment like you do. Houses leave behind clues. Your nose knows mildew. If there’s mildew, water is sitting somewhere underneath.

In older homes especially, watch for galvanized water lines — rust builds up inside, kills water pressure, and in a lot of municipalities if you’re doing any renovation at all they’ll make you replace them all the way to the city water tap.

Related

foundation, water intrusion, inspections, structural damage, pro diy, grandfathering