Removing old mastic glue and chunks of old parquet flooring from the slab with an air chisel before installing new laminated floor in the den in our 1961 ranch house in Southaven. Ugh! Quite a chore!
If you can get the flooring up, they do make a safer solvent you can roll on and soften the glue, then scrape it up with a wide putty knife. This stuff was black and I was wanting to avoid a gooey mess, so I went with this method.
This room is 16′ x 12′. Chiseling it up was VERY labor intensive. I took frequent breaks and I’d work on it a while and then quit. In areas where the glue was thinner, it was hard and brittle and chipped right up. But in areas where it was thicker, it was somewhat gummy, and that was tough and slow going. It would sort of roll up in a gummy strip and i’d have to scrape them off the blade frequently. I’d have never gotten it up without this scraper, but I don’t ever want to see one of these things again!
Working straight through, I would guess it took maybe…. 12 hours of scraping. But I take frequent breaks and work on other projects to break up the monotony. So I got it done over the course of about 3 days. If someone asked me what I’d charge to do a floor like this, I’d have to seriously think about $1,500.00 minimum. It’s about 3 times the labor of putting the stuff down.
I used this Harbor Freight Air Scraper I borrowed from my nephew and it worked well. It probably wasn’t that expensive. Even if you used it just this once, you’d save buying one over paying someone to do it.