Suziesnowflake is spot on -- if the PO's had to replace subflooring, something's wrong. The problems with window flashing are espeically bad in stucco houses because the stucco traps the moisture inside. Our house was 6 years old when we started noticing a pretty strong musty smell in several of the bedrooms and in the laundry room. We had noticed the smell on and off for the past couple springs but it would always go away before we'd get worried enough to do anything about it. That year, the smell stayed and got stronger. We had no signs of water intrusion anywhere and no previous mold problems. We took the electrical outlet plate covers off the wall and noticed that the smell seemed to be coming from inside the walls. Also, the screws inside the outlet boxes were rusty. We had several contractors out and none of them could find any sign of a problem - a few of them even said I was crazy (not so bluntly but that was the implication) becuase they couldn't smell or see anything. Finally, one day, we pulled a piece of slightly punky wooden trim off the outside (the contractors all said that that's just a normal thing that happens to wood trim and we should just plan on replacing it once in a while). While we were removing it, the crowbar went through the house. All of the sheathing was completely moldy and rotten - you could put your finger through it. We ended up spending over $100K (none of it covered by insurance) to replace the entire outside of the house - we stripped it down completely to studs and drywall. Some of the studs had to be replaced. We had to replace all the insulation - it wasn't wet, but was holding the musty smell. We washed the worst of the mold off the studs with bleach. We reinstalled insulation, new sheathing, and new siding (while PROPERLY flashing the windows). It was a nightmare and we're still recovering financially and emotionally (I'm a stress eater and I packed on a good 40 lbs in less than a year from the ordeal). I hope that your problem isn't this serious, but if your home is recently built (last 15 yrs or so), there's a good chance that it is. After my hard-earned lessons on flashing and homebuilding techniques, I can even today drive around to new developments and watch new million-dollar houses being built with improper window flashing. This is going to become a big problem over the next 10-15 years as all of this hidden moisture starts to manifest itself. I'd definitely do some investigating since the sooner you catch it, the less there will be to fix (and maybe you can go after the previous owners for some of it if you can prove they knew there was a problem). Start by taking the outlet plate covers off in the rooms with the smell and sniff -- is the smell stronger in the outlet boxes? Are the screws inside the outlet boxes rusty? If so, you've got moisture in your walls and that's not good. I'll link to my website if you want to look at the gory details of our house....but it's not for the faint-hearted, LOL! And if you do look, remember that even with all that damage and rot, we never had ANY signs of moisture or leaking inside -- all we had was the smell which, like you said, was worst in the change of seasons (spring especially). Here is a link that might be useful: Worst case scenario....

Hi Stefanie, I would be glad to help if I can. I got an air purifier and it seemed like it helped a little as long as it stayed on. We ended up moving our bedroom to the one next to it and turning the musty room into a studio. I took the air purifier out to put into the new bedroom and the stinky room got really bad and thick. I happened to ask my exterminator when he came by for a routine spraying so he checked the attic above the room and said everything was normal critter-wise but theres no fan so it gets very hot. He said he used to do moisture/mold remidiation and would take a look to see if anything explained it. We have a tree with large branches that hover above that room . It looked like rainwater was pooling in the gutter above the window and if you looked under the brick, there was a lot of moss and black staining. He said to trim the branches, treat the black stains, and get a de-humidifier for that room and see what happens. Since taking his advice, I have noticed a big decrease in smell. I am still cautious as to whether this will permanently solve it but its enough of a difference to where the room is bearable to be in now.

We have the same issue too. 2nd story window. Had a moisture company come out and didn't detect any moisture on the outside. Had it resided with LP Smartside and installers saw nothing. My husband and I just ripped off the trim last night. I can't let my kid in this room anymore. We found one spot. Smack dab in the middle of the window between the two different panes. These are vinyl windows. The pictures actually look worse than in person. Could just this little bit make this big of an odor? Is this the install or the window. We just resided and wondering if they'll have to take the siding out and we'll have to redo that too. We're going to do whatever we need to do. Does anyone with experience think this is a flashing issue? A crack in the window. The water does weep out of the weep holes. It looks darker than it is because I did a bleach wash.

It's coming from an old yeller towel crammed up between faucet and sink from underneath. You must lie on your back looking up to see it, As others warned, mold is bad for you so wear resperator and eye protection while removing the towel. Once the towel is removed you will need to repair a tiny leak in hot supply connection,otherwise it drip's on cabinet. For less than what you waste on septic pumping you could hire it done.