To find a leak in a crawl space, look for standing water, wet or sagging insulation, drips under bathrooms and the kitchen, and musty smells. Start with a careful look from the entrance before going in, since crawl spaces can be tight, wet, and near wiring.
Safety Before Going In
- Do not enter if there is standing water near electrical wiring or equipment
- Wear gloves, long sleeves, and eye protection
- Use a battery flashlight, not a corded light
- Tell someone you are going in
- Watch for sewage smells, which mean a drain may be leaking
Where to Look
Follow the water lines and drains from where they enter the crawl space toward the fixtures above. Leaks often show up under toilets, tubs, showers, sinks, and the washing machine. Look for drips from joints, wet spots on the soil or vapor barrier, and insulation that is soggy or hanging down. Rust stains on pipe hangers can mark an old drip.
Signs of a Leak From Inside the House
A musty smell in rooms above, soft or warped floors, and a water bill that keeps climbing can all point to a crawl space leak. Checking the water meter with everything off helps confirm a supply leak.
Water That Is Not a Plumbing Leak
Not all crawl space water is from pipes. Rain and groundwater can seep in through foundation walls and vents, and condensation can form on cold pipes. Water that appears mainly after storms is more likely outside water.
Note where you see water and when, so the cause is easier to track down. Photos with the date help show whether a wet area is growing.
If you cannot safely reach or find the source, a leak search under the floor can pinpoint it. For drainage or moisture problems in the space, you can ask a plumber to inspect the crawl space by calling (833) 603-1840.