Sorry for the length...
The problem: Smelly, finished basement. Only in the summer. The rest of the ywear it's fine. It's not a full underground basement, the rear door goes out to the lawn. Musty, cat smell, water, etc.
There are three rooms. The main room is probably 22' by 19', the next room is the kitchen/laundry room about 12' by 12', then the bathroom 6' by 7'. Then another small room where the laundry shoot it, maybe 7 by
4'. The ceilings are 7' high. I gutted this basement 7 years ago and framed it with 2 x 4s, new sheetrock, studs, took out some HEAVILY water-damaged 2 x 4s in the laundry room and bathroom. Put in indoor/outdoor carpet, new windows, new door, new wiring, etc.Before we bough it it flooded every timed it rained fairly good. We had a drain put in around the perimeter of the house and solved that problem.
The wall in the laundry room and laundry shoot room is the one that is completely underground. I applied Drylock to this wall about 5 years ago. 5 years is what the can said was it's limit. So that may be a problem, but we're getting no moisture on that wall.
The other problem. My wife runs a daycare down there and it's embarrassing when the parents drop off their kids to say the least.
We have a dehumidifier running all the time. But it's just not removing the odor that well. There are three windows in the main room plus the entrance door. When we have all the windows open the cross-breeze seems to mask the smell good enough.
But we don't want to mask it, we want it gone.
Do we just need a bigger dehumidifier or is this problem just inherent to the house and we just have to live with it?
A one car garage butts up against this living area with an entrance door. Our two outdoor cats basically live in the garage at night. We have two litter boxes in there. Sometimes (a lot of times) they miss the litter box and the garage stinks.
I'm sure this gets into the basement somehow but the smells seem to be entirely different.
So we're frustrated in not really knowing exactly where the smell is coming from and how to get rid of it. So much so that we might sell it. We're worried the 2x4s are moldy and might have to come out again, etc.
I think I should have a home inspector come in and see what they say.