Your Place: A mysterious wet spot calls for some sleuthing

Today's lead question was crafted so nicely that I decided to forgo the usual introduction to the column and let reader Melanie Mackin do it for me:

"I've been watching too many CSI television shows, because here's the problem:"

The crime: Sopping wet carpet.

The scene of the crime: Family room, underneath three floor-to-ceiling windows. The wet spot is rectangular, about eight feet long by six inches wide, which mirrors the length of the three windows. The middle window is actually a door that goes to the outside patio. Multiple attempts to seal the door with caulk failed because of the door needing to be open and closed. We are only guessing that the door is where water enters the room because we cannot see any water or drips entering; not in the window, not on the wall, not around the door jamb, not on the ceiling. This part of the family room sits over the open basement, not a crawl space. There are no signs of wetness on the ceiling or wall of the basement underneath this spot.

When the crime occurs: After or during a medium-to- heavy rain.

What's so confusing: The window seals are good - none are broken. There is no visible water coming down the ceiling, walls, or windows.

So, how does the criminal make restitution? (How do we fix this?)

Answer: I'm no Gil Grissom (for which I'm extremely thankful, having once been addicted to the original CSI), but without looking at your house, and noting that the wet spot on the rug has the same length as the three windows, I would assume that there is an opening of some sort behind the windows at their base - behind the wall - that needs to be sealed.

If there was no carpet there, the water probably would be noticeable on the basement ceiling. The fact that it is a spot and not a flood may mean that a minor repair is required.

If this is a recent installation, you need to call the installer, after looking at the warranty, to see if the fix is a minor one.

You also should call the manufacturer of the windows to see if there has been a recall of its products, or at least determine what constitutes proper installation.

I had a somewhat similar issue with the door to my garage workshop. It seemed tight, but there would be moisture on either side of the doorway inside after a rainstorm.

The door sweep had rotted at the bottom, and that was allowing the small amount of moisture inside. I spent $12 for one at the hardware store and the problem was solved.