I have a 2-story home with basement built in 1963. It has hardwood floors over a wooden-slat base. Underneath the floorboards there is some sort of vapor barrier visible in the basement.
The basement has a storage area that is divided from the rest of the basement by a wall and door. All of the plumbing is along one side of the house. Over the past month, I have noticed twice a puddle of water directly under the door jam to the storage area in the basement. At first I thought the dehumidifer had leaked and a puddle had run to a low area of the floor. Yesterday I noticed the puddle again and liquid dripping from above the storage room door jam. It had a greasy feel to it but was clean/clear. I slit the vapor barrier above this area and the liquid came out (probably about 8-12 oz in all). This area is not under a bathroom or kitchen and is in the middle of the basement area. The door is next to the stairwell wall (at foot of stairs), but their are not water pipes along this wall. It really has me puzzled. I have lived in this house for 7 years now (with multiple other problems!) but this is the first time this has happened. Any ideas?