There are two principal types of finishes used on wood floors--penetrating seals and surface finishes. Each requires about the same care; but when it comes to removing stains or restoring the finish in heavy traffic areas, methods vary.

It is important for you to know how your floors were finished so you can decide on the proper floor care product. Your builder, realtor or flooring installer/finisher should be able to tell you what type of finish was used.

It will also be helpful to know the brand names of the finishing products, particularly the final finish coat. If your floors are factory finished note the name of the manufacturer. Keep this information in your household data file to help you determine the proper floor care products.

As a general rule you can be sure your plank or strip floor was finished at the factory if it has V-shaped grooves or bevels along the edges where the boards join and sometimes where the ends butt. This may be only a slightly rolled edge, or a healthy bevel. NOTE: Plank flooring which has been custom finished at the job may have beveled/grooved edges.

If the floor has no bevels, it probably was custom finished on site after installation. To determine what kind of finish was used, call the builder or floor finisher if possible. When in doubt, try smudging the finish with a finger or scraping the finish with a fingernail or sharp instrument in a hidden area or corner of the room. If the smudge is noticeable or no clear finish material is scraped up, the floors have likely been waxed and maintenance should follow the guideline for penetrating sealer with wax.

If no noticeable smudge is evident and/or clear finish was scraped up, follow the maintenance procedure for a surface finish.

Surface Finishes

Polyurethane, "Swedish" finish, Moisture cure urethane, and Water-based urethanes, to name a few, are blends of synthetic resins, plasticizers, and other film-forming ingredients which remain on and protect the surface of the wood. All are durable moisture-resistant finishes. These finishes are generally available in high-gloss, semi-gloss, satin and matte, except moisture-cured urethane. Any one of the above surface finishes is a good choice. They are the recommended finish for kitchens or similar areas where there is exposure to water splashing or spills.

NOTE: Penetrating sealers may have also been used as an undercoat for surface finishes.

"Polyurethane," oil modified polyurethane, is generally the most common surface finish. The finish tends to amber slightly as it ages.

"Swedish finish," acid curing urethane, is also a very durable finish, generally harder than polyurethane. These finishes are clear, fast-drying and resist yellowing.

Moisture-cure urethanes are the hardest finishes. Some are non-yellowing (check can label). Gloss is the most common sheen.

"Water-based finishes" are urethanes or blends of acrylics and urethanes that are fast drying, moisture resistant, durable, and resist yellowing. As the name implies the vehicular component is water.

Most manufacturers of surface finishes recommend no waxing. Wax will, in most cases, be slippery. Once waxed, the floor may not be successfully re-coated to rejuvenate it, but will have to be completely sanded down to raw wood to restore the finish.

"Varnish, Shellac and Lacquer finishes"  These are surface finishes rarely used today, and generally are not considered as durable as the more modern finishes. Shellacs are the softest and show water spots. Varnishes are harder but not to the extent of modern finishes and will show more ambering over time. Lacquers are hard and brittle and scratch easily (very flammable when applied).

Don’t damp mop shellacs because of water spotting. You can use a slightly damp mop on the others if not previously waxed. For finishes which have been previously waxed, maintain by waxing occasionally. When traffic wear is noticeable, complete refinishing and changing to a newer finish is most often the preferred choice for repair.

"Polymer finishes"- There is a third classification of finishes known as acrylic impregnated or an irradiated polymer. This is used primarily in commercial applications. Each brand of flooring using a polymer or acrylic impregnated finish have specific maintenance procedures which should be obtained from the manufacturer.

Caring for Surface Finishes on Your Floors

Vacuum and/or dust mop regularly.

• For general cleaning of soiled areas, dip or spray a clean cloth with the manufacturer’s recommended cleaner. The cloth should be slightly moistened, not wet. As you clean the floor follow by wiping the floor dry. If manufacturer of the finish is unknown, spray-mist areas of floors with a mild cleaner (i.e. non-abrasive counter-type) follow by wiping with a sponge mop or cloth pad mop, and dry up residue.

NOTE: Spray mist only as necessary. Do not apply moisture unnecessarily, vacuum instead. Contact the finish manufacturer to determine specific recommendations for cleaning the finish. Ammonia will damage or dull many surface finishes and should not be used to clean your floor.

Repairing a Surface Finish

With special care and skill, you may be able to repair polyurethane finishes yourself. Such repair may be necessary after stain removal or water damage. Use steel wool or fine sandpaper to remove layers of the finish from entire length of the affected boards. If necessary, stain and let dry completely. Apply the same type polyurethane as the original finish to the entire boards, being careful not to build additional finish coats on surrounding strips. Read application directions. Taping the perimeter of the area with a quality release masking tape is helpful. Allow ample drying time. After the finish is dry remove tape.

CAUTION: Don’t attempt this if you have an older varnish. The older finishes are almost impossible to repair and match successfully. Lacquer and shellac, however, repair more easily.
For a small, relatively inconspicuous area you might get by cleaning with steel wool followed by paste wax. You won’t get an exact match but it could serve as temporary repair. The alternative is sanding to expose bare wood over the entire room and applying new finish.

Penetrating Seals

This finish has been widely used on residential floors. As its name implies, the sealer penetrates or soaks into the wood pores and hardens to seal the floor against dirt and certain stains. The penetrating sealer may also contain a stain to impart additional color to the flooring. These finishes may be used in all areas but kitchens and daily eating areas where frequent water contact is likely. This finish does protect from surface moisture but will stain, dull, and/or whiten if the moisture remains on it for more than a short period of time.

At the surface it delivers a low gloss satin finish that wears as the wood wears. The satin luster helps camouflage surface abuse. However, since the finish wears with the wood, eventually traffic lanes may show a lightened or dulled area. When an area does begin to show wear, it can be refinished or renewed. The renewed areas can be made to blend into the existing finish without lap marks or other obvious signs of repair.

The beauty and wear resistance of wood floors finished with a penetrating seal may be further enhanced by wax. A wax coating forms a barrier against the most frequent kind of abrasion, can be easily renewed, and imparts a soft shine to the floor.

Use wax with these two cautions:(1) the wax (liquid buffing or paste) MUST BE DESIGNED FOR USE ON HARDWOOD FLOORS and (2) don’t use a liquid that has a water base. Check the label. Some manufacturers recommend their water-base products for wood, however, our association believes only a solvent- base product should be used. Generally, solvent-based waxes will have the odor of mineral spirits.

Follow the manufacturer’s directions for applying the wax and buff it well. This is done preferably with a 16-inch buffing machine available from rental companies. You may also buff small areas with a household buffer or by hand with clean cloths or pads.

Caring for Penetrating Sealer and/or Wax Finishes

Vacuum and/or dust mop routinely.

Vacuuming is the best way to remove surface dust and dirt before it gets "walked into" the wax and dulls its luster. Vacuuming also pulls accumulated dust from the grooves of prefinished and plank floors.

When floor luster has dulled a bit and scuff marks begin to show, buff with a machine or by hand to restore luster and polish out scuffs.

After four to six months of wear, inspect your floors closely to see if there’s been a dirt build-up or if the wax has discolored. If your floors were originally finished in a dark tone, you may see a lightening of the finish in traffic areas. After vacuuming and before any other procedure, buff an area, if the shine is not restored apply a new thin coat of wax. Buff well to restore the luster.

Smaller areas of floors finished with a penetrating sealer and/or wax can be repaired and re-waxed more easily than floors finished with a surface finish.

For smaller areas with imbedded dirt, abused areas, and lightened areas in traffic lanes, use a liquid cleaner or cleaner/wax combination. Remember, make sure the products are solvent rather than water base. The label may say it contains naptha or petroleum distillate. Follow directions. For dark floors, choose a product in a compatible dark color. Spread it with steel wool. Rub to remove grime and the old wax, then wipe clean. Let floor dry. Buff if cleaner/wax combination was used or re-wax and buff if not. When using paste wax, wrap in a "wad" of cloth and apply an even thin coat. The warmth of your hand and rubbing friction melts the wax for proper application. If dull spots remain after drying apply a second coat to dull areas and repeat.

For general deep cleaning of excessively dirty floors, and refurbishing an entire floor to restore to near original conditions, use the liquid cleaners or restorers applied per directions with steel wool pads and a commercial buffer (15" - 17" diameter).

Follow with waxing using either a paste or liquid using the same buffer for final polishing.

If your floors are stained (colored), it’s a good idea always to use a colored wax or cleaner to help maintain the original color. The best place for obtaining hardwood floor care products is your local dealer, which handles floor finishing products.

Caring for special surfaces

White and Bleached Floors -- Because of their light color, these floors are usually lighter than the soil that accumulates on them, like white carpet or vinyl, they are more susceptible to showing the effects of dirt and traffic than natural or darker stained finishes. Therefore they need-and deserve-more attention than others. Vacuum or sweep often. Wipe up liquid spills immediately. Follow the maintenance procedures recommended for the type of finish used. With factory or on-the-job finishes the light-tinted or "white" floors most probably will have some shading changes over time.

Something else you’ll probably notice with such finishes are tiny separations between the flooring strips during dry seasons or long heating periods. The amount of moisture in the air causes wood to expand or contract. When humidity levels are low, the flooring will contract and the separations become even more prominent than at other times. The contrast between a white floor surface causes even tiny separations to appear larger. Shrinkage and movement is a natural characteristic of wood and will occur with each heating season.

Distressed Wood -- These are floors that have been wire brushed to remove the soft portion of the wood, giving it an antique, textured appearance. The resulting uneven surface tends to trap dirt, so we recommend vacuuming. If soil remains, sweep with a stiff bristle broom and re-vacuum.

Such floors are usually stained a dark color with penetrating sealers and waxed to further convey the aged wood effect. What remains after the wire brush treatment, however, are only the toughest wood fibers, and these are somewhat resistant to penetration by the finish color. That means more frequent color renewal, which can be accomplished by the use of a wax or cleaner/wax combination of the proper color to maintain the original color tone.

Source: http://www.nofma.org/