Recent content by JosephNY

The slab is 7" thick and was poured in 1960 and is about 160' above ground (apt building). The installer polished a small area and put a dark stain on part of it, so we could see what it looks like. Here it is:

Do you think I should leave it unstained? There are certain areas where the mastic has slightly stained the concrete. Thanks!

Is the charcoal stain a serious recommendation? If so, can you please point me to some pictures? And I'd really appreciate understanding why the slab is a POS (I have no emotional investment in whether it's a POS or the best slab ever; but I do want a nice floor). Thanks!

Here's some from this morning (yesterday's work). All mastic is up. Grinding has started. I'm told that some mastic is in holes/cracks and needs to be drilled out - ugh. And, that in some places the mastic stained the concrete below a little bit. I'm very open to (and would be appreciate...

Here's progress -- Mastic is gone, they're starting the first grind now.

The owner of the company and a couple of guys have all done this many times. But, as they've said, each job is different. This mastic, they say, is the worst they've ever seen. It's 60 years old, put on thick, and gums up their machinery. They didn't finish today, but they're much closer --...

Thanks guys! They're shooting for finishing the removal of the mastic today and a first grind tomorrow. Will keep the pictures flowing.

Last batch today:

And more:

Update: The guys started 2 days ago. The black mastic stuck to the floor and applied in 1960 to hold down 9x9 oak parquet on concrete is far more difficult to remove than anticipated. They tried several machines/blades as well as mineral spirits with and without sand, etc. It's getting...

Great idea -- will do.

Thank you all so much for your insight and advice. I've hired a guy who has tons of experience grinding/polishing concrete as well as having an artistic eye. We'll start grinding and see what we find as far as cracks, blemishes, aggregate, etc. and take it from there. We're not going for pure...

I'm renovating an apt in a building built in 1960. The floor was wood parquet glued (black, horribly tough stuff) to a 7" thick concrete slab w/rebar and large stones. My wife is determined to have a beautiful concrete floor. I'm wondering if the slab can be ground/sanded/buffed/sealed...