Sanding and finishing should provide a basically flat surface with allowance for variations related to different cuts (quartered vs. plain sawn), individual grain patterns, and the overall original condition or flatness of the flooring. The sanding scratch patterns should not have prominent variation as viewed from a standing position. The overall texture and natural color of the wood can affect ultimate color. The natural variation in color should not create an objection.
CommunicationRecently a contractor called about a 4” red oak plank flooring installation that was site finished and his customer was objecting to the dished grain. The customer showed the condition by opening the front door, standing on the porch steps and pointing to the reflected light across the floor. The contractor acknowledged the floor had dished grain. He also stated that he sanded and finished the floor like he always does. For 95 percent of the homes in this area, this wouldn’t have been a problem. We discussed that acceptance should be made from a standing position in normal lighting and the customer was being excessively picky. He then stated that the rear of the great room in question was a wall of windows from the floor to the cathedral ceiling. I asked if he had explained to the customer the reflected light would emphasize and magnify any irregularity? “NO” was the reply.
What if he had angle sanded the first cut with finer grit, rather than using 40-grit on a straight cut? He also could have “hard plated” instead of the aggressive screening for the final pass. We both agreed that the dished grain could have been avoided or at least significantly reduced. “But that would have been extra,” was the reply. We ultimately agreed that the window wall should have waved the red flag and initiated conversation about reflected glare. By not communicating with his customer, he had placed himself at risk of having to refinish the floor. I suggested he send the customer to the NOFMA web site (www.nofma.org) to review publications about customer inspection and acceptance found in Finishing Hardwood Flooring.
Another pitfall is following the direction of the primary contractor or builder. Many times I hear that the builder had to have the floor finished “NOW!” in order to complete construction. Then, 20 sub-contractors showed up to finish their work and trashed “your floor.” But, the builder says he will take care of any problems. Sure, you will be pressured to re-sand the floor to keep his business, or you may have to refinish later when the finish peels because of contamination. This may even involve moving the homeowners out to the local hotel. If you haven’t previously cautioned the contractor/builder in writing of these likely consequences, you will probably have to bear the cost of repair. If you have given official written notice, then at least you have a position from which to negotiate the costs.
What about the pitfall of following the instructions of the customer? “I want the color darker, so leave extra stain on the floor.” We are the professionals and have to be frank and inform the consumer what we can and cannot do. Too much stain on the floor likely results in finish that peels or walks off prematurely. The topcoats stick to the stain, not the underlying wood fiber. Again, set up proper customer expectations. Darker means a heavier sanding scratch from coarser grit or water popping the grain so more color can remain on the floor. Both situations come with consequences. A coarser scratch means a rougher looking floor that might be an objection. Water popping takes more time and care, thus more cost. Either condition can require extra time for finish to properly dry for the next coat.
Another recent situation mentioned by a consumer is filling the floor during the finishing process. This particular consumer wanted the characters in the rustic flooring to show. The contractor filled the areas with a light color that contrasted with the dark color of knots and other blemishes. The consumer was totally unsatisfied. I asked if the contractor discussed filling before finishing. Again the answer was “NO.” The opposite also happens: the consumer assumes the characters and blemishes in the flooring will be filled and they are not.
To this point we have discussed some of the issues that occur from dialogue, or the lack of dialogue, with the consumer. What about our own operational errors?
Basic DetailsAnother pitfall is not paying attention to basic details. Keep your machinery and accessories clean and in good working order. Machines with clogged motors, out of balanced drums, and/or cheap or worn drive belts do not run smoothly and create inconsistent sanding patterns, resulting in splotchy color, waves and streaks. Continuing to use an abrasive that has hit an exposed nail or the grill of the heating register can also result in streaks and many times swirl marks that are obvious from the standing position. Not keeping the site clean results in trash in the finish, and footprints from the transmission fluid tracked in from the burger joint.
A common mistake is not following manufacturers’ direction. The new finish formulations being marketed as a result of VOC regulation require we review the instructions. Dry times have likely changed, recoating times may be different, and mixing directions (particularly with water-based finishes) are specific to the brand of finish and application techniques (pads, rollers, T-bars, brushes, etc.).
Remember, with water-based finishes; use a moisture meter to check the wood moisture content before and after application. You will know when the moisture is again the same and you can recoat. Do not assume that an overnight dry time is sufficient for coating over oil stains. Some of the darker stain colors may take two or three days to dry, particularly if the weather is humid.
How about the actual sanding of the flooring? Just because Dad used a 36-, 50-, 80-grit sequence for sanding doesn’t mean we have to. Start with a 50-grit on an angle (15- to 30-degrees may be enough to efficiently flatten the floor). This is particularly true with the many closed grained species that are very hard. If you don’t put the rough scratch in, you don’t have to sand it out. With the wider plank and open grained woods (ash and oak), don’t dish out the softer open grain; use finer grits and hard plate.
Don’t forget the handwork: scraping and hand sanding at corners, direction changes, and around feature areas like borders, and hearths. Blend the edges with the field to avoid the picture frame appearance. This requires hand sanding and proper disking technique. Finally, apply the finish according to the directions.
One of the pitfalls most often encountered during finishing is lack of ventilation. We don’t need a hurricane for ventilation, but when application is complete and the finish is dust free, provide air exchange to evacuate the volatiles. Failure to do so can lead to improper curing, a soft finish, discoloration, streaking and leveling problems.
Remember:Set up customer expectations on the front end. Pay attention to the details AND don’t cut corners.