Blotchy polyurethane coating

Q: We applied a water based polyurethane to our freshly stained floors. We have only done one coat with a roller. We have places where there was not enough polyurethane on the roller and places where you can tell it was stopped to reload the roller.

Should we apply the second coat and see how it looks or buff the floor then reapply?

A: This really is a job best left to professionals. Most water borne coatings can be recoated without buffing between coats “provided” this is done within the number of hours after the previous coating specified by the finish manufacturer. Also, not all finishes apply well with a roller, and there are a list of specifications that need to be met to have any hope of really good results. Since you say the floor has been stained a particular colour, it will be difficult to buff this finish without also removing the stain, since water borne coatings generally are lower solids and therefore leave a thinner film on the floor. If you have to buff, it is going to have to be with a very fine abrasive. Please do not use steel wool. You may have better success in applying with a “water wiz” which is basically a foam pad.