Peeling finish can be a frustrating issue for floor finishers. Sometimes the coats will lay down flat and smooth and look good after the floor finisher has left, only to receive a call later that the finish is separating from the floor. This often leads to some head-scratching trying to figure out how it happened. There are many causes for this to happen so one really has to reverse engineer their sanding and finishing sequence to figure out where things went wrong. Some of the most usual causes include:
- Surface contamination below the finish.
- Not abrading or using too-fine of a grit abrasive between coats.
- Hot coating a subsequent coat after the window of opportunity for hot coating (manufacturers specify how long a finish can sit, before it needs to be abraded).
- Sometimes the elasticity of the coat beneath is not compatible with the elasticity of the coat applied.
- Stain that is heavily applied, double stained or insufficiently wiped off.
- Using stain that is not meant for flooring.
- Naturally occurring oils from some species.
- Improper tacking solvent used between coats.
All of the causes listed above must be considered when a peeling issue is discovered. Thankfully these issues can be avoided. It is important to refer to the manufacturers application instructions when finishing newly sanded floors, and consult with the manufacturer before re-coating over an existing finish.
For more information regarding peeling finish, please refer to page 64 of the NWFA Technical Publication Problems, Causes, and Cures.