I have a basement leak that happens every other year on average, after either a very heavy rainfall, or melting of a lot of snow. It occurs on only one wall of the basement, and I've detected water on the floor from opposite ends of that wall. This leads me to believe it's the foundation wall.
I had someone come in and open up the drywall from the inside a few years ago, and he said he couldn't find a leak. He then attributed the leak to an old window, and charged me to replace it, along with the drywall he ripped out. After another leak a few years later, I know it's not the window.
I've had spalling/cracking bricks on the outside of that wall replaced several years in a row, and there's a cement walkway right up against the entire wall, with no spacer in between. I also notice green mold outside around the basement windows, which are below ground level.
Does this sound like it could be the foundation leaking? If so, is this an expensive repair? The house is only 30 years old; what would cause this to be failing so soon?