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hardwood floors removed but now tar on concrete How too?

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Mar 13, 2014, 02:10 PM
hardwood floors removed but now tar on concrete How too?
Has anyone experienced this and what did you do? The house was built in the 50's. We removed our hardwood floors and also used alot of chemicals to remove the tar/mastic/cutback from the concrete single floor home. Now there is a residue of tar left and sealing will only make the tar active. the concrete is not completely clean and also now the doors are 2 inches too high. The question. how to bring up the floor and seal off the tar in doing so?
Mar 14, 2014, 06:53 AM
Why was the floor removed, and what did you think you where going to do for a finished floor?
What do you have for heat? The reason I ask is because if it's forced hot air there was suppose to be about a 1" gap under the doors for return air flow. So allow for that plus the thickness of the finished flooring.
PS, you do know that cut back glue may well contain asbestos, right?

Google "Soy mastic remover" for a safe way to get the rest of the mastic off the floor.

Apr 22, 2014, 04:53 PM
Hello joecaption
We wanted to take the old out is why. We still do not know how we want to finish the floor. We'd like to go all concrete but the work still needing to do and the mastic possibilities you mentioned may lead us into installing procelain tile or covering it with something. Between the doors and the concrete is about 3 inches. Plenty of room for return air. What do you have for an opinion of what to put down ont the concrete?
Apr 23, 2014, 01:17 AM
The only thing that would cause you any problems would be if you were trying to use this concrete as a finished floor - which is sounds like you are not going to do.

Your concrete can be covered by carpet, a floating engineered floor, tile or even a second pour of concrete. None of these will be affected by the tar residue. It's really down to what kind of floor surface you want or need as your options are open.

Apr 23, 2014, 09:26 AM
Great opinions to consider. I believe we have learned about this residue enough to need to cover it. Unfortunately. The finish job the guys did back then on the conrete had its own cool looking design on the concrete. We were trying to use it, but I believe I cannot go with this concrete unless it were sanded down to remove residue left and that is very expensive.. Anyone have other opinions/ideas. Thank you for these.
May 05, 2014, 08:02 PM
Since you are undecided why not try some products to see if they work. A quick search and......

Maybe a citric acid...?
May 24, 2014, 07:22 PM
We had this same stuff. Even if you remove it, the concrete will not look good enough to leave bare, as the mastic stains it. We used a laminate flooring and it looks great.