How to refinish a hardwood floor — the complete manifesto

When my husband Todd and I found the house we wanted to buy, we could tell from pictures online before even visiting it that many of the floors were in rough shape. We decided that we could take on the challenge of refinishing the floors, along with the help of a friend, Anders, who’s skilled in all manner of home repair and improvement things (seriously, dude’s a wizard).

The Turret (as our home has come to be called) is a three story Victorian-style brick twin. The living room floors were newly replaced in 2005 and still look great, but the second and third floor bedrooms were another story (no pun intended). The previous owners ripped up the carpeting there when they bought the house, but they didn’t refinish the floorboards, and also left a number of carpet tacks, staples, and other random bits embedded in the wood. On top of that, it seems like they must have done a lot of moving around of heavy stuff because some of the rooms had gouges and scratches all over. Despite all that, the wood itself was in good condition, considering it’s almost 100 years old. It’s long leaf yellow pine, which (I’ve been told by friends who do architectural salvage) is a floor covering you don’t see too often these days. A hundred years ago, long leaf pine was used as a sub-flooring material over which parquet or other fancy floor coverings would be laid. Never mind that it’s gorgeous in its own right; it was never meant to see the light of day, much less take the daily abuse of having people walk on it. But we wanted to give it the glory it deserves!

The first step in bringing our floors up to their full beauty potential was to eyeball them carefully for metal bits that might get in the way of the sander. This involved crawling along on hands and knees in a grid pattern, using a hammer and a nail setter to pound down nails that may have come a bit loose over the years and a screw driver and pliers to pull out staples and other bits from in between the boards. It’s very important to remove all such things because A) they could mess up your sander belt and cause you to go through them faster than necessary — which is a waste of money, and B) you don’t want that stuff winking at you forever once you put on the varnish.

We were fortunate to have a friend who owns a drum sander that he was kind enough to lend us free of charge. If you’re not as lucky, it’s worth investing in a rental, as a drum sander covers more ground faster than a belt sander. Drum sanders look kind of like those floor buffer machines or giant vacuums. They can be tricky to use –- they’re heavy, and they want to pull away from you due to the motion of the belt going ’round on the floor. Your shoulders might hurt after running it for a few hours, since you’re basically keeping it in check the entire time it’s on. Be careful when sanding –- if you leave the sander in place for too long, you can sand a depression into your floor! It’s a powerful piece of machinery. Wear goggles and an OSHA-approved mask for particulate matter, as sanding kicks up a LOT of sawdust, and you don’t want to be breathing that in. (TIP: If, like us, you’re planning to repaint as well as do floors, do the floors first: you don’t want sawdust sticking to fresh paint that hasn’t cured yet!)

Anders went over our floors once with 60 grit sandpaper and once with 100 grit. The lower the grit, the more coarse the paper, and the more material it takes off. 60 grit removed the old remnants of varnish on the floors, and the 100 grit smoothed it out. Because the drum sander is large there are spots where it just won’t go, like inside closets and close along the wall. For these areas, we used a hand-held belt sander (again, 60 grit and 100 grit sandpaper) and then a Dremel tool on the corners and crannies. You’ll want to sand with the grain of the wood to keep it looking great.

There were a couple small areas where we were forced to sand against the grain (awkward corners, depressions in the wood that the sander just wouldn’t catch) but generally you want to stay with it at all times. Depending on the age and condition of your floors, there may be imperfections that just have to stay there (unless you want to replace entire boards). For instance, our third floor was originally three rooms but the previous owners knocked down the walls to make one large suite. You can still see the marks on the floor where the walls were, because the wood underneath the plaster got no oxygen and didn’t age. It’s a slight imperfection, but I actually like knowing what that part of The Turret used to look like.

This is also the part of the program where I wrote a little love note to The Turret and slipped it in between the floor boards…

Once you have the floor sanded down, it’s time to make sure it’s super super clean. Get thee to a shop vac!! Vacuum thoroughly up and down the cracks between the floor boards and in all those aforementioned crannies. If there was carpet, keep your eyes peeled along the edges of the room for stray carpet strings and pull them out with pliers or tweezers. This is also the part of the program where I wrote a little love note to The Turret and slipped it in between the floor boards so the people replacing the floors another hundred years from now will know who we were.

You may notice that during the sanding process some nail heads got burnished to a nice silver sheen. They may look puuurdy and new, but they’re going to stick out like sore thumbs forever once the varnish is on so you’ll want to cover them. Our method was to use a brown Sharpie marker and just color them in. It’s not perfect, but it cuts the glare on those little shiny nail heads. One piece of flooring in the library had been badly patched with some sort of white plaster or epoxy. We colored that in with the brown marker too, which turned out to be a mistake (the large patch of marker didn’t take the varnish well) so I would recommend using the marker technique only for small patch-ups. Once that’s done, vacuum again for good measure. If there’s carpet abutting the area where you’ll be refinishing, see if you can peel it back a bit so you don’t get varnish on it.

Now you’re ready for varnish! There are multiple varnish/stain options out there, some more environmentally friendly or expensive than others. We went with Minwax Polyurethane High-Build Semi-Gloss, which is an oil-based product that provides some shine, but not the mirror-like sheen of high gloss (high gloss looks great, but shows scratches very easily). There are water-based stains out there that are greener, but they tend to cost more and also require longer drying time. Minwax takes only 4-6 hours to dry, which means that we could get two coats on in one day (which was important to us, as we were completing this project before moving in). Talk to your local hardware store about how much varnish you’ll need for your floor area. As far as getting the varnish on the floor, Anders has found that using a foam applicator designed for water-based varnishes actually works better than applicators designed for oil-based products. It’s kind of like a foam mop head and tends to be neater and easier to manipulate than the wool sort.

Before starting, make sure you have several paint trays with disposable liners. I use one for clean up, one for storage (if you douse the applicator with mineral spirits and let it sit in a mineral spirit bath, I’ve found that it will keep overnight for use the next day) and one for the polyurethane. Moisten the applicator with mineral spirits so it’s damp before you do your first dip in varnish – much like a paint roller, it absorbs better if it’s slightly damp. Before opening your container of varnish, make sure you put on an OSHA-approved vapor mask (they’re different from those for particulate matter) as the stuff can make you loopy really really quickly. Work with the windows open and a fan or two pulling fresh air into the room, and chemical-laden air away from it (the breeze also helps with drying).

When applying your finish, work from one side of the room towards the other, going with the grain of the wood in long, even strokes. Once you get a line down, drag the applicator lightly over it to smooth out and streaks and get a nice continuous stripe. Overlap your lines slightly and watch out for ridges or beads of excess finish – if they dry there, they’re going to be there forevs. Work your way out of the room, as you cannot step on this stuff until it’s completely dry unless you want your footprint forever on your floor. Wait for the recommended drying time for your product to elapse before putting on additional coats. We did three coats in each room of The Turret, and the floors look amazing.

Taking on such a project is a LOT of work. The process itself is relatively simple – sand, clean, refinish – but parts of it can be tedious and back-breaking. On the other hand, it gave us an amazing sense of ownership in The Turret. Before we even moved in, we had done something to majorly improve the look and value of our home. I don’t think any of The Turret’s previous owners had refinished these floors, and it made us feel special. I enjoy having such an intimate knowledge of that part of our house and really feeling invested in it. Not to mention feeling great about having completed the entire project (almost 1000 square feet worth of floors) for under $1000. If you have the opportunity to commune with your dwelling on such a level, I highly recommend it. Now, on to the next project!!