Q&As: Wood Species ID, Squeaks and Applying Hardwax Oil

Hardwax Application

Do you have any hardwax oil application tips?

Jay Daniel Moore, owner at Richmond, Va.-based Antique Floors LLC, and NWFA Regional Instructor, answers:

Some people buff it on, but for my hardwax oil jobs, I like to use a 10- or 18-inch flexible steel trowel, especially if the job is large. I find the buff-on method is much slower and doesn’t deliver as much product in the grain. When troweling hardwax oil on, first pour it into mustard bottles, then drizzle it on the floor parallel with the grain and use a stand-up trowel to mimic the motions used with a T-bar. But unlike spreading water-based urethane, do not leave any excess—in fact, remove as much excess as possible, much like you would troweling sheetrock mud off a wall. The more you remove right away, the less work you have to do when you come back to remove the excess and burnish the floor. Absorption doesn’t take place immediately, so consider troweling the entire room quickly, then coming back to remove the oil.

Keep in mind that the edges need to be paid close attention to. Use thin green pads to remove the product and white polishing pads or synthetic-blend hog’s hair pads to polish. When bidding a job with 2,000 feet or more, consider finding thin green pads rather than the thick ones—they are often half the cost.

These techniques can be tweaked to fit your particular hardwax of choice, but our experience is that they work universally. Of course, always follow the finish manufacturer’s directions. 

Exotic Squeaking

I just installed Brazilian walnut over a plywood subfloor, and now the owner says areas of the floor are squeaking. I checked the subfloor before installation and stapled the flooring myself. How can it be squeaking?

Scott Taylor, a Milwaukee-based NWFACP Inspector and NWFA Regional Instructor, answers:

I go on lots of inspections for complaints about noisy floors; when there is a floor squeaking or making noise, there’s always movement. That means either the subfloor or the flooring itself is moving. In this case you say that you checked the subfloor before installation, so we’ll assume the subfloor is not the issue.

That means something has gone wrong with the fastening on this job—because the floor isn’t fastened well to the subfloor, there is movement up and down, which creates the squeaks. Oftentimes in cases like this, there aren’t enough fasteners. (In areas focused on high-production building I see plenty of floors that are skip-nailed—only every other row is nailed—but I’ll assume that isn’t the case here.) Did you follow the correct fastener schedule for the width of the flooring and make sure there was a fastener within 1 to 3 inches of all board ends? If you did, the problem could be the fastener blowing through the tongues. You say that you stapled the floor—what was the pressure on the compressor? Since exotic floors are typically very hard woods, oftentimes guys turn up the pressure to try to set the fasteners. The problem is that when the pressure is too high, the fasteners can blow all the way through the tongues, causing cracking and splitting. Sometimes you’ll see splitting so bad the tongue is separated from the board. This is more common with staples than cleats, and that would be my guess for what happened on this floor. 

In the future if you have to nail a hard floor, look into what the manufacturer suggests. Believe it or not, some recommend cleats over staples; this is because there is only one penetration point. No matter which you use, always monitor your compressor’s psi gauge to make sure the fasteners are being seated properly. It is obvious when you have too little air pressure, but not when you have too much.

Species ID Help

I need to do a repair on a floor where I can’t figure out the species. Is there anywhere I can send a sample to ID it?

Brett Miller, National Wood Flooring Association director of certification and education, answers:

Yes, there are several independent labs that can help with this. We get quite a few calls about this at NWFA, and I find many people are unaware of the resources available.

First, you can send a sample to the U.S.D.A. Forest Products Lab. This is a free service, although it can take up to six months to get results. For a fee, you can also send samples to universities with wood science laboratories (examples are Virginia Tech, NC State, and University of Minnesota-Duluth), or to other independent labs specializing in wood species identification. Fees and turnaround vary, so I would recommend contacting each individually to get pricing and availability.

Independent labs aren’t just useful for species identification. You can also get Janka/hardness testing and moisture content testing, and can determine specific gravity, fastener strength and mechanical properties of specific products. Labs are also available for testing things like ply adhesion or composition of engineered flooring—they can take a sample of a product and determine where the failure is happening and why. Many labs can also test for formaldehyde emissions.

Likewise, similar services are available for wood floor finishes and adhesives. Many labs can run adhesion tests, taber abrasion tests, coefficient of friction tests or chemical analysis of failures to help determine cause. 

For a long list of testing labs we’re aware of, see below. 

TESTING LABS: