There’s a Wrong Way to Refinish Floors and Then There’s This Way

There’s no better surprise than peeling back layers of old carpet or tile and finding hardwood floors waiting beneath. When we tore out our kitchen and bath recently there were some unpleasant surprises, but there was also the most amazing gift from the house: Below the ugly faux terracotta, ’60s linoleum, and plywood, there was original heart pine subfloor.

I immediately texted a small local hardwood floor refinishing business. Not because we can’t do it ourselves, but because I wanted it done right. This flooring is made of old growth pine from 500-year-old trees cut down in the late 1800s. To say it’s irreplaceable is an understatement.

Yes, yes, you can certainly clean and refinish your own floors. And an awful lot of what we see on home shows and read online encourages us to DIY to our heart’s content. You can do anything, right!? But the truth is, there are professionals who make a living at things like this for a reason. Refinishing floors is a craft. Doing it well takes specialized equipment, professional grade supplies, and experience. And I learned that the hard way.

When we redid the floors in our Detroit house we had next to no budget, so borrowing a sander and tackling it ourselves was really our only option. But the finish was rough, we left marks where we’d stopped and started the machine, and since we couldn’t maneuver it close enough to the baseboard, my hack was to paint a border on the floor to hide it. Did it work? Sure. Did it honor the nearly 100-year-old house? Sadly, no.

The Victorian we call home now was built in a grander era. I can’t imagine ever having the resources to bring it to its full glory, but when and where we can, we bring in the best people for the job. And 99 times out of 100, that’s not us.

So, really, what’s the difference between a pro and a handy homeowner job, you might wonder? To find out, I sat down with Duncan Smith of Old Louisville Hardwood Floors. Smith got his start at age 12 when his uncle Cookie set him up with refinishing equipment in the middle of an elementary school gymnasium and showed him how it’s done. Since then Smith has seen his fair share of others’ DIY work. What are the most common problems he sees? See below for his thoughts.

Like our less-than-perfect floors, they’re often rough. The cause of that, he explained, is that we didn’t buff it between coats of the polyurethane sealer. It just didn’t seem necessary, I thought at the time. Plus, I wanted to hurry up and get it done. A light buffing between coats is needed, though, Smith said, “so the two different layers can chemically adhere to each other. It also helps smooth out the air bubbles and particles of dust and floor. If you don’t smooth those after the first coat they keep building and get bigger.”

And about those stop and start marks. When the drum sander is turning, it’s turning anywhere from 1600 to 2000 rpms. When it sits in one spot for too long, Smith said, with “the weight of the machine and gravity, the only place you can go is down.” Yep, down into the floor where you’re leaving grooves, which is especially noticeable with softer wood like pine.

A DIYer is also using a machine they’re not familiar with. The rental machines at the store are “about half the weight and strength of the typical sanders professionals would use so you can’t be as aggressive,” he said. When someone does it every day “there’s a flow,” he said. “You’re using the same equipment, you know how it cuts.”

For a novice, “It will take you twice as long as it would a professional even if you’re using the correct grit sandpapers,” Smith said. And on that–there’s no one size fits all approach. I seem to recall Googling “How to sand a floor” and following the internet’s advice for what grit paper to use in what order, and then running out halfway through and having to go back out for more. Smith advised that that’s not unusual, since store-bought sandpaper is half as good as what he can buy in bulk, not to mention twice the cost. Smith and his crew, on the other hand, are monitoring the floor throughout the process. They know the signs for when they’ve gone far enough, and they know when a stain will or won’t come out with continued sanding.

This is another issue he sees all the time. “You see it a lot with folks who are trying to stain their floors darker,” he said, “especially with open grain woods like oak. If the two boards are sanded differently, they’ll accept the stain differently and one will inevitably be darker or lighter.”

Looking at the gleaming, gorgeous floor in our almost-finished kitchen, I now know it’s some of the best money we spent on this renovation. And the thing is, it wasn’t even that expensive, especially relative to what a new hardwood floor would cost. According to ImproveNet’s cost guides, new floor installation will run you, on average, $4,113. Refinishing a floor, on the other hand, averages $1,511. That’s definitely a lot more than doing it yourself. But, after seeing firsthand a pro’s results, versus mine (not to mention the enormous hassle), I’ll never do it myself again.