I recently removed existing linolium squares from my basement floor, only to find a black glue-like residue covering the concrete that is slightly tacky in spots. Do I need to remove it somehow, or can I paint right over it?
Debbie W. ~ Wichita, Kansas
I would recommend removing that old gluey stuff no matter what you put on the floor. That black stuff is an old type of floor tile mastic. Bear in mind that if it is still tacky now after years of sitting under floor tiles, it will be tacky years from now, even if it is covered in paint. Your local paint store may have some products that will help you in the removal of the old floor mastic. Good Luck!
I would be careful removing the old glue. The tile and glue of that era many contain asbestos.
The black glue is called “Cutback”, and was used almost exclusively before the new clearset adhesives came on the market. And yes, the older formulas did contain some asbestos as a filler. However, the asbestos only becomes friable (airborn particles small enough to enter the lungs) if the adhesive is totally dry, and it is disturbed by sanding or scraping. It needs to be removed if you are going to stain or paint the floor. Home Depot and Lowes both have a non volatile solvent that you can use to remove the adhesive. Keep in mind that it’s a nasty job to do, but is absolutely necessary to insure that the new finish on your floor does not come up.