What signs should I look for during a showing or open house?
Buying a home is one of the biggest investments you’ll ever make. While most buyers are looking at the granite countertops and open floor plans, as a waterproofing expert, I’m looking at the baseboards and doing the sniff test.
Water issues aren’t always deal breakers, but it can be a great negotiating tool. Here is how to spot hidden moisture and foundation problems like a pro during your next open house.
Table of Contents
1. The 30-Second Sniff Test
Your nose is often a better inspector than your eyes.
- Musty or Earthy Odors: If the basement or crawl space smells like wet cardboard or a damp forest, there is probably moisture or mold growth nearby.
- Overpowering Air Fresheners: Be wary of multiple plug in scents or candles burning in the basement. Sellers often use these to mask the scent of mold or dampness.
2. Visual Red Flags
Don’t just look at the walls; look closely at the bottom six inches where the wall meets the floor.
- Efflorescence: Look for a white, chalky, or powdery substance on concrete or brick. This is actually salt left behind after water evaporates and a sign there is seepage.
- The Leak: Look for staining or dampness specifically where the wall meets the floor. This can indicate hydrostatic pressure which is water pushing up from under the house.
- Peeling Paint or Bubbling Wallpaper: Moisture trapped behind the finish causes it to lose its grip.
- Cracks: Hairline cracks are common in settling homes. Note that horizontal cracks or stair-step cracks in brick/block are serious red flags for structural pressure.
3. The Cover-Up Signs
Sometimes, what you don’t see is more telling.
- Fresh Paint in One Spot: If only one wall in the basement has been freshly painted, they might be covering up water stains or mold.
- Boxes Off the Floor: Are all the storage bins on pallets or plastic shelving? The current owner might know from experience that the floor gets damp.
- New Baseboards: If the upstairs has old trim but the basement has brand-new baseboards, ask why. They may have been replaced after a flood.
4. Checking the Outside
Most basement water starts in the yard. Take a walk around the exterior:
- Negative Grading: Does the dirt slope toward the house? That’s a funnel for rainwater.
- Short Downspouts: If the gutters dump water right at the base of the foundation (less than 6–10 feet away), that water is headed straight for the basement.
- Clogged Gutters: Look for dark streaks on the outside of gutters or washed-out soil underneath them.
5. Quick Homebuyer’s Toolkit
You don’t need a tool belt to be an expert. Bring these two things to every showing:
- A Flashlight: Shine it at an angle against the basement walls to see ripples in paint or hidden cracks.
- A Marble: Place a marble on the basement floor in a few different spots. If it quickly rolls toward a wall, it could be a sign that the floor is uneven or the foundation has shifted.
Found a Red Flag? Don’t Panic.
Seeing these signs doesn’t mean you shouldn’t buy the house. It just means you need to know the cost of the fix before you sign. Many of these issues are common and can be solved permanently with the right drainage or vapor barrier.
