Blending old and new wood flooring

Q: We recently hired a professional to add additional hardwood flooring and to refinish all the other rooms to make them blend. The entire floor was not sanded; instead it was feathered in. When the blending was completed and a finish coat was applied there were wormy looking bubbles along the blending line.

The professional sent him workers back to resand the floors and apply a new coat. Unbelievably when the new coat was dried and we got to take a look, the entire floor (old and new) looked like there were flecks of dirt all over it. What did they do wrong? Do we need it sanded and a new coat applied again? Can too many coats be a problem? I’ve noticed that the “old flooring” does not look as good as it did before all of this, even with all the scratches that were on it.

A: Blending old and new is near impossible to accomplish. It sounds like they had some drying issues, often caused by environmental factors, i.e., drying too rapidly. That is regarding the original bubbles. If the floor area, surrounding area and pail of finish being used are not clean, contamination will result. Coating can be very tricky, and at times, even when everything known is done correctly, things can still go astray. Generally a light buff with a polisher and fine abrasive and a thorough clean up before coating will suffice to apply another coat. I would caution against applying more than 3-4 coats initially, since the solvents in each coating need to evaporate for the finish to cure. If solvents become locked into the previous coats, it could take some time to properly cure and harden.