Just purchased a 1930s house with some significant 'deferred maintenance'. We pulled up the wall-to-wall that the PO must have put down just before putting the place on the market and have discovered a number of exciting things:
1 - Linoleum from what may be the original design. The linoleum itself was thankfully asbestos free, but I need to send the mastic out for a test.
2 - The stairs had some strange brittle plastic like material nailed and glued to them, which it looks like the carpet installers must have just nailed and stapled right through.
3 - Oak hardwood floors downstairs. Lots of dark spots, but they should look good after some quality time with a drum sander.
Item #2 is a bit perplexing. In addition to the brittle tread material being obnoxious to try and remove, we're noticing that either the stairs themselves or the tread material give off a horrendous odor when wet. Fairly confident it isn't mold, but unsure what it is. It's staggering enough that we can't continue to work in the area for a couple of hours.
My theories are:
1 - Old shellac. This seems like a possibility, but I've worked plenty with shellac and never smelled anything like this before.
2 - Some type of old glue. I thought it could possibly be hide glue, which has a bit of a funky smell, but I've spent enough time around luthiers to know that it isn't bad enough to make me leave the room.
One thing we've observed is that it seems like wetting it makes the situation worse : at first we tried simple green (we were trying to keep lead dust to a minimum), and that was bad. Today we tried white vinegar and water. Also bad.
I'm at a bit of a loss as to what I need to do with this stuff, but i know it needs to go. Any ideas?