Hi everyone, I recently bought a house in Brooklyn NY, which was built in 1901. Two floors, plus a basement. On the first floor are the original parquet wood floors. The parquet "tile" at the bottom of the stairs sinks in when you step on it. Seems like maybe the sub-floor underneath is broken. My hope is that I can possibly fix it from underneath, by adding support to the sub-floor from the basement. I figured I'd take a look and worst case scenario call in a floorer. The basement has a drop ceiling, so I removed a couple of tiles to take a look. I expected to see the exposed joists, sub-floor, etc, but here's what I'm looking at (see the photos). Basically strips of wood covered in some sort of cement-type stuff. To get to the broken section of the sub-floor I'd need to remove a small section of this wood/cement stuff. You can see in two of the photos that some sections are already removed (not by me), but unfortunately not the section that I need. Anyway I'm not sure what that cement stuff is, but I can pull it away with my fingers for the most part. It occurred to me that maybe this stuff contains asbestos so I'm posting to see if anyone has any insight before I continue any further. Thanks, much appreciated.

Hi folks, A few years ago, when Hurricane Irene hit, the carpet in the finished portion of my basement got damp in multiple spots by a small amount of water that infiltrated the room. That carpet and pad was laid directly on the concrete floor by the previous owner. Fearing future mold, we had all the carpet removed. I'm now preparing to re-carpet that room. I'm laying down DMX 1-step dimpled underlayment directly on the concrete and then laying a floating subfloor on top of that. The 5/16" height of the underlayment should be enough to keep the subfloor dry if water ever comes in again, but just in case, I'm going to use either Advantech 23/32" T&G OSB or GP DryPly Sturd-I-Floor 23/32" plywood. Both are water resistant. My questions are: 1. Does anyone have any thoughts or opinions on Advantech or DryPly? 2. For a floating T&G subfloor, do I still need to leave a 1/8" expansion gap at the 4' ends? 3. Should I use a construction adhesive in the groove? 4. Lastly, for anyone who is familiar with water resistant plywood/OSB......Is only the factory edge impervious to water? When I cut a piece to fit in near a wall, is that cut end not protected? Thanks to anyone who can help me!!!!!