Looks like a few rooms the radiator is near the dark spots. Maybe house closed up with no one living in it and radiators got frozen, cracked and leaked, water pooled in low spots. That's my best guess.

I'm looking at a 74 year old home with a masonry foundation...in Maryland. Brick foundations are NOTORIOUS for being 'wet'...not just damp....but wet. In the photo listed under kitchen/dining, you have a pic of the washer/dryer area in the BASEMENT...notice the REALLY DARK brick sitting just underneath the window...see it? Yep...that's a nasty indicator that something is wrong. Brick takes a LOT of moisture to turn 'dark'. Like a LOT!

I've also noticed that the dark spots aren't 'old'. They look like they are CONTINUING to have issues. Wood doesn't turn that dark...and then stay dark once it dries out. It takes a LONG time to get that dark...and it only STAYS dark if it remains WET (not damp....but WET). The sponginess confirms it...the wood is still wet.

Your instincts are correct. There is something going on with this home. I've noticed the windows are new(er). And the wet spots are very very close to windows....which again makes me wonder if windows are part of the issue.

If the windows are an issue, the exterior walls are also suspect. The only way I would be willing to put a bid on this would be if I had a moisture meter on me and was able to spend several HOURS in the home testing all the wet spots.

A home inspection probably won't be able to find the 'issue' because they are not allowed to open up walls/ceilings during an inspection. The amount of caveats that would HAVE to be in place (for me) for a bid would be TERRIFYING for the existing home owner. They probably wouldn't go anywhere near the offer.

https://www.fredericknewspost.com/archives/soggy-yards-useless/article_991426b3-94b6-5989-b329-fc098608af77.html

Have a look at the link above. It is a brief newspaper article written about the water table issues in this area of the USA. It is an old article (2004) but it establishes the issues in this area. And with global warming and sea levels rising, things won't get much better.

@SJ-- yes, I think you are right about the windows being involved. I showed this to our contractor who thought that there might be multiple issues as the worst part of the damage is in the front hall and nowhere close to a window. He believes that there are plumbing leaks as well as rotten seals around the windows and that the brick may need repointing.

We own three homes in MD- 1882, 1850 and 1893 build years respectively. All three have stone foundations and all three have damp basements. Its just the way things are here. We have done extensive regrading and water remediation to get to a certain level of comfort but its never going to be bone dry in any of those basements. So its not as though we are scared of this reality. This house, despite being much newer than those we own, seems much worse than anything we have seen before. We aren't bidding on it as the price would have to be lowered by at least 100K in order to make it palatable with all the work needed to update and repair the issues. We were asked to look at it as another friend knows the owners (an estate sale, the kids want nothing to do with it) and thought we might breathe some new life into it as we have done with other properties. Great location on a desirable street, but far beyond what we want to get involved with.

I would venture to guess multiple issues as well. Take a close look at that flat roof as well.

@millworkman, heck, take a look at the state of the main roof in general! That isn't a cheap repair either.

What G & S Said.... Pet Stains.

They appear to be pet stains to me too. I have seen similar to the hallway, when carpet was removed. I am betting that there were area rugs, on all the areas, that have those spots, and a very old pet, or a pet that wasnt let out as often as it should have been.

@cat, I don't think these were pet stains. Maybe one or two. The house has been vacant for some time and the wood was damp/mushy. If an animal had come in and was using the place as a bathroom you would have smelled it. There was a note in the disclosures that the stains had been caused by a leaking pipe and the problem had been fixed. There was carpet at some point that had been ripped up.

Come on! These are obviously pet stains. The house has a basement, right? If this was a water issue bad enough to cause stains that dark, there would be signs on the basement ceiling. Pet's urinate on rugs/carpet, the urine soaks the carpet and pad, the ammonia chemically burns the wood. I'd bet money on it, and I'm NOT a betting person unless it's a sure win.

In a couple rooms I can see an outline where there used to be an area rug. The stains are within the area covered by a rug. The foyer appears to have had wall to wall carpet at one time and there are stains all over.

Maybe there was a leaky pipe at some point but it didn't cause these stains that are textbook examples of pet stains.

Cats, lots of cats.

I would agree except for the current wetness and lack of smell. The owners has been deceased for some time and the house vacant. if it were pee spots and cars had caused them it would be an unmistakable odor were it current.

I did a whole-house remodel for a couple with elderly dogs (read: poor bladder control.) The hardwood floors had stains like the ones in the picture. They're pet stains. Consider that a number of them are in rooms with no radiators.

Occam's razor (or Ockham's razor) is a principle from philosophy. Suppose there exist two explanations for an occurrence. In this case the one that requires the least speculation is usually better. Another way of saying it is that the more assumptions you have to make, the more unlikely an explanation.

In other words If it looks like a duck, swims like a duck and quacks like a duck, it's probably a duck.

Yes I'm familiar with Occam's Razor. But also unwilling to plunk down cash on a house with a series of mysterious issues that no one can.explain satisfactorily. Again these are current stains ..wet. It doesn't smell of urine. There's no pets that live there and have not for some time. Sellers disclosed a leaky pipe and plumbing issue. if it were just old pet stains they would say that...a much more straightforward cause with less chance to scare off a buyer. I get it... this is what it looks like. But I don't think it's the whole story. I appreciate the input!

Why did you post here? Who here has better info about conditions and who said what than you?

Why would you even consider such a money pit? Got a $100K deal where you can tear it down and rebuild all new on the property?

The floors have obviously been buffed and coated with shellac to seal in the pet stink. Much of them will need 100% replacement. As with just about everything in the house. The green painted trim made me as nauseous as the pic of that hallway. Their listing price is delusional. It needs as much work as it lists for.

There are enzymes that claim to neutralize pet odors from urine. Perhaps one of these was used. Realtors often use ozone generators to eliminate pet and cigarette odors before listing. Absence of odor can be explained. I suspect that if you were to use a wood floor scraper to remove some finish and wood off one of the spots in the foyer, you would get an odor.

Nothing you've suggested as possible causes would make those concentrated spots on the floor, especially when the surrounding areas look to be completely unaffected.

As I wrote before "Maybe there was a leaky pipe at some point but it didn't cause these stains that are textbook examples of pet stains.". Maybe there's a leaky roof. Maybe there's been leaky windows. These should all be investigated, but with 36 years doing only wood flooring, and being called in to look at all manner of issues, I'd say it's pretty clear to me that these are from pet stains.

I disagree with GreenDesigns somewhat. I don't know the pricing of houses in the area but being an hour or so from DC must affect prices. It looks like a cool house and property. Paint color is a poor reason to reject a house since it's easy to change (and most people want to make it their own). The roof looks sketchy but not too hard to replace. The foyer floor would have to be completely replaced, painted or maybe stained really dark. The other floor areas could be evaluated to determine whether furnishing or rugs would hide some of the stains, patch if necessary and refinish.

Good luck!

Did you have a moisture reading done, to see if in fact, the floors still have moisture?

Oh that’s pet stains alright. And that wallpaper! Those bathrooms! That kitchen! The whole entire house needs gutting and redoing. Or torn down and built new. It’s not close in enough to make either option economically feasible without getting it at half of what it’s listed at.