Historic Floors Wear Thin Under Sanding

Half the fun of owning an historic home is dealing with the quirks and idiosyncrasies that come with restoring it. Old parquet and strip floors present a unique challenge. Because parquet floors are fragile and very thin, you need to be cautious in your approach to the refinishing process. Don't worry about choosing a finish until you deal with preparation.

The paramount consideration is avoiding damage to the floor during preparation. Avoid sanding if your parquet floor isn't thick enough to withstand it. You may have only three-eighths of an inch in thickness before you hit the tongue. For that reason, consider taking the harder but safer route of hand scraping or stripping with chemicals. Strip-style floors are generally thicker than parquet and suitable for sanding.

If you do sand, remember that repeated sandings will grind down the surface. Each sanding removes about one-sixteenth to three- sixteenths of an inch from your floor. To determine how thin- skinned your floor is, try looking under the molding and baseboard, or take out a floor heating register. Floor joints in these older homes are usually about one-inch thick--fairly wide but not a problem. Reduce the thickness of the board down to much less than seven-eights of an inch, however, and it might yield to weight. You could be inadvertently adding an extra spring in your step.

On the other hand, if your floor has been well-maintained, you may skip major preparation and go directly to finishing. Despite it's durability, polyurethane looks tacky to some folks in an historic home. It's up to you to decide whether stripping and replacing it with an historic finish is worth the trouble. However, many vintage floors have the period-style varnish or shellac coating. You can apply another coat of the same finish to retain that authentic look. Just remember that shellac doesn't withstand alcohol or water spills.

First determine what was used originally. Test a small area by sanding and applying your chosen finish. If it adheres and looks right, you've probably got the same finish. If not, don't attempt to mix a varnish coating on top of shellac, or vice versa--they don't work well together. Waxing will preserve the finish and create just a hint of shine. You'll need to rewax the floor periodically and dust mop to keep it free of dust and dirt.

Sources used in creation of this article include Popular Mechanics magazine.