Unexplained holes or damage inside the house
Unexplained holes or damage can appear suddenly in hidden areas like closets or crawlspaces, leaving homeowners unsure whether to seal them up or investigate further. This uncertainty triggers immediate panic about structural integrity or hidden pests, preventing people from feeling safe or knowing the correct next step to take.
What the numbers show
Counted from the threads quoted below. How we count
- Most of it landed at once — the busiest month was September 2026, with 11 people.
- This comes up 15.9× more often in r/HomeMaintenance than across the site as a whole.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1filling the hole with water using a hose to check for voidsDid this help you?
- 2sealing the hole, packing the dirt, and regrading away from the houseDid this help you?
- 3Guessing the cause from online forum responsesDid this help you?
- 4Checking for active dust near holesDid this help you?
- 5inspecting for dust or evidence of termitesDid this help you?
- 6considering whether previous occupants hung frames or items on the wallsDid this help you?
- 7taping the holes back up with foil duct tapeDid this help you?
- 8calling a plumber or handyman to inspectDid this help you?
- 9posting pictures online to ask communities for adviceDid this help you?
- 10waiting to see if the issue worsens over timeDid this help you?
- 11Having an HVAC technician look at the ductwork to insulate or repair as neededDid this help you?
- 12Spraying the underside for mold remediationDid this help you?
- 13Negotiating seller concessions based on the inspection findingsDid this help you?
- 14asking online forums to identify strange equipment marksDid this help you?
- 15reaching out to the landlord and sending photos of the damageDid this help you?
- 16calling exterminators or specialists to inspect the damage before continuing the projectDid this help you?
- 17stopping the renovation project to investigate and address the issueDid this help you?
- 18Consulting online forums and communities for reassurance from other homeownersDid this help you?
- 19Spackling and painting over hairline cracks as a quick fixDid this help you?
- 20Adjusting appliance feet to compensate for uneven floorsDid this help you?
- 21Shining a light into the hole or poking around with a screwdriver to check depth and hollownessDid this help you?
- 22Filling shallow holes with hydraulic cement or concrete patchDid this help you?
- 23Consulting an expert or home inspector to evaluate the issueDid this help you?
- 24trying to scrape it offDid this help you?
- 25calling the landlord to report a potential leakDid this help you?
- 26Replacing only the damaged section of the subfloor instead of doing a full tear-outDid this help you?
- 27Using specialized antimicrobial cleaners or white vinegar instead of bleach to treat porous surfacesDid this help you?
- 28Avoiding homeowners insurance claims for maintenance issues to prevent premium hikesDid this help you?
- 29Buying new power tools mid-project to speed up the unexpected extra workDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“We'd kept this closet closed all winter, and opened it to find this.”source ↗
“What the heck am I looking at here?”source ↗
“Noticed that this beam under where our toilet is, is white with some greenish flakey stuff on it? Is this mold? Also don’t even know where to get started taking care of it if it is mold….”source ↗
“What are these holes for throughout my dryer vent duct?”source ↗
“Had an inspection and they are saying this is damage and I need to replace the whole vent line which has never been an issue in the past 8 years I’ve had my home and every year I get a cleaning and inspection done.”source ↗
“Saw this in my cupboard, also on some other wood around the house. Canada btw”source ↗
“Does anyone know what this could be? A strange plastic/honeycomb/webbed looking protrusion on an interior wall, 1930s apartment complex in NYC. I'm assuming somehow related to water damage since I have water leaks through the upper window frames but I honestly have no idea.”source ↗
“I'm worried the couch has likely been there a long time, so it could be worse than what it's presenting.”source ↗
“That's my worry...clearly they've had their couch there for a long time. I am concerned the fix would be more than just drying out the area of subflooring that is currently wet. Trying to decide what's worth negotiating on some seller concessions.”source ↗
“The wall beside the stairs has a bit of a ridge to it, but it is not at floor level.”source ↗
“Is it something humidity related? And is it concerning?”source ↗
“I just bought the house 2 weeks ago and the inspector didn’t point it out and I just noticed it.”source ↗
“Could be moisture behind the wall. I had something similar in a bathroom wall and we tracked to a roof leak.”source ↗
“Started with a simple toilet replacement. Then I found out they put new flooring was on old flooring. And the old flooring was stained from an old water leak. Then the underlayment was waterlogged and now the sub floor is molded... Now I have to consider a full bathroom remodel depending on how far some of the mold goes.”source ↗
“I have one goddamn day off a week and this is how I spend it.”source ↗
“I have all the new wood and a flipping moisture barrier to go with new flooring since the last guy didn't know jack about shit.”source ↗
“Hole I found while digging through the rock beds. Some very loose/soft dirt there too.”source ↗
“Seal off the hole and forget it exists? Or keep panicking?”source ↗
“My friend I just went through this exactly. Sorry it’s happened to you, but this is just how it goes sometimes as a homeowner.”source ↗
“I already know its just a section for the sub floor thankfully. Each part is easy but all together its a chore for sure. Its just more annoying realizing a circular saw would make this infinitely easier.”source ↗
“We moved into an older home a couple of months ago and it quickly became apparent that the previous owner had painted over cracks in the walls and ceiling.”source ↗
“Also, we discovered that the kitchen floor is slightly sloped. The inspection report was clear and the slope wasn't mentioned, but then some doorframe cracks and this ceiling crack (pictured) became visible.”source ↗
“If we had noticed the sloped floor, we wouldn't have bought this house.”source ↗
“Is this ceiling crack in the realm of normal, or is this something we should get an engineer to investigate?”source ↗
“And do we have any recourse with our home inspector?”source ↗
“was just trying to run a new outlet, cut into the drywall, and found what looked like sawdust piled up along the bottom of the stud bay.”source ↗
“turned out there'd been a slow leak behind that wall for who knows how long. glad i found it mid- remodel instead of after closing everything back up”source ↗
Where this came up
People with this problem also raised
- 4Inherited a house with sudden damage and no idea what to do
- 5What to do if your rental house has severe structural damage
- 5How to spot hidden subfloor damage covered by new OSB
- 24How to find hidden home defects after buying
- 55How to identify tiny unknown bugs found inside the house
- 5New equipment installed with dents or mismatched parts