Orange spots on wood floor

Q: My oak hardwood floor has orange spots all over, after my contractor refinished my floor. What are the spots from? No stain involved.. just sealer and polyurethane.

A: Never heard of this one. There are far few details to even make an educated guess. What finish was used? How was it applied? What does your contractor think it is?

Follow-up Q: My contractor does not know. He used Park oil based polyurethane, and sealer, since no stain was applied. I have done my floor myself in the past with beautiful results using the same products. The two possible causes I think may be the problem: he did not sand all the old polyurethane off, and he used paint thinner to clean the floor after sanding.

A: It wouldn’t be the paint thinner. Oil based polyurethanes have mineral spirits as their main solvent. Not getting all the old finish off could be the cause.