Hardwood Floor Finish Repair
DEAR TIM: There are several places on my hardwood floors where bare wood is showing. The finish and stain have been worn off. Some floors have been stained and others are natural. Money is tight and I simply can't afford to have the floors completely refinished. Is it possible to make repairs to the floors and have the damaged areas look great? Is this a DIY job? How would I proceed? Holly B., Attleboro, MA
DEAR HOLLY: Your situation reminds me of a remodeling job I did many years ago for a demanding architect at his own home. Part of the job was installing some new oak parquet flooring at a doorway. The existing floor was stained and the new flooring had to match both in finish sheen and color. The customer was skeptical that I could do it. Guess what? I got a perfect match and so can you!
Here's what you need to realize starting this repair. You can't make the floors look any worse than they are. Just about anything you do will be an improvement. That being said, I do suggest that you practice what I'm about to share on some scrape pieces of hardwood flooring if you can get some from a local business that installs hardwood. Call them and you'll be able to get some scrap wood easily.
The first thing to do is to sand the damaged areas. If there are deep scratches, you'll have to use coarser 60-grit sandpaper to start the process. Only use this coarse sandpaper in the area of the deep scratches. You will be using several different grits of paper from coarse to very fine to complete the sanding.
You can sand by hand if you have smaller areas less than 6 inches square. Be sure to use a sanding block. If you have access to an electric palm sander, this tool will make the job go faster.
Sand the damaged area and extend the sanding to the edges of the floor that are not damaged as you use the fine-grit sandpapers. Just go over onto these edges about an inch. Use finer grits of sandpaper advancing finally to 240 grit. Aluminum oxide sandpaper, it's usually a medium brown color, is a great paper to use for this project. The wood needs to be as smooth as glass before continuing.
Remove all dust with a vacuum that exhausts outdoors if possible. Wipe the sanded area with a tack cloth. If the floor is natural with no stain, the next step is to apply the first coat of finish.
Floor urethane comes in both oil and water-based formulations. The water-based urethanes typically will be crystal clear when they dry, and will not impart any color to the wood. The oil-based urethanes tend to have a slight amber or golden appearance once they dry.
To see which one best matches your existing floor color, you can sand a tiny area of flooring, about the size of a postage stamp, in a closet or under some large piece of furniture. Using a cotton swab, apply a drop or two of each of the urethanes to one half of the sanded area. Allow to dry to see which one achieves the best color match.
If you have to match a stained floor, realize that the sanded wood must be satin smooth so the stain doesn't come out too dark. You may have to purchase several small cans of test stain to get an exact match. When you apply the stain and it's wet just after you lightly wipe off the excess stain from the wood, the color you see at that instant is the color the stain will be after urethane is applied to it.
Urethanes come in varying shades of gloss. To match your existing floor gloss, you'll have to clean it well to see what it is. If you make a mistake and select the wrong gloss, you can easily re-coat the repaired area until you get a close or perfect match.
You'll need to apply at least three coats of urethane to complete the repair. Read the label to determine how long you need to wait before you apply each coat. You'll have to lightly sand the urethane before you apply the next coat. Use the tack cloth to get up all dust before you apply the urethane.
Apply the final coat of urethane so it stops at the edges of the wood strips and not in the middle of a single piece of wood. This natural break between the strips of wood flooring helps to disguise minor differences in the sheen of the urethane. If the sheen is not perfectly matched, wait about two weeks and try to burnish it with an old towel to make it blend better with the slightly worn finish of the hardwood flooring immediately adjacent to the repaired area. Believe me, your floor is going to look so much better!
You can watch a video that shows how to match wood stain. Simply type "wood stain video" into the search engine at www.AsktheBuilder.com.