How To Refinish Hardwood Floors: Step-By-Step Guide

Hardwood floors are meant to last the lifetime of the property where they are installed, but over time, they’ll naturally need refinishing. While you can hire a flooring contractor to do it, it’s also possible to do the job yourself using the right supplies and instructions.

At Red Label Abrasives, we have provided professional contractors and DIYers alike with the abrasive products they need to strip and refinish hardwood floors of all types. In this article, we provide you with a step-by-step guide for getting outstanding results

Is Your Flooring Actually Hardwood?

To successfully refinish your hardwood floors, you must first determine what type of floor you have. It might seem obvious, but there are many types of flooring masquerading as hardwood, but which are actually partially or entirely made of other materials, and each requires a different refinishing method.

Hardware look-alikes include: 

• Laminate: Synthetic materials are layered and embossed with grain patterns to mimic the look and feel of natural wood. In general, laminate flooring feels like a hard plastic, which makes it easy to identify. Refinishing laminate is nearly impossible, but chemical abrasives can be used for recoating.
• Engineered: An engineered wood floor consists of a thin layer of hardwood bonded to a cheaper material, typically plywood. This flooring can be refinished once or twice, provided the layer of real hardwood is thick enough to sand down without hitting plywood.

It is best to refinish solid hardwood floors because they are made of solid planks of wood. However, even with this material, you should still make sure there is enough wood left to sand. To attempt a full resurface, you need at least 3/4" left. 

The easiest way to find out how much material you have left is to remove the floor grate or vent to expose the floorboards. Alternatively, if there are no such openings, you should remove the threshold from the doorway, as there will typically be gaps between rooms where a board or plank will be exposed.

Last but not least, if you're still unsure, you can remove a piece of baseboard trim from the wall in the room that needs to be refinished. If the floor had been resurfaced in the past, there will be a slightly raised area underneath the baseboards. 

Step #1: Get the Room Ready

Pro Tip:Do you need to finish your floor or simply clean and polish it? An easy way to determine its condition is by performing a water droplet test. Water droplets that soak into the floor right away indicate exposed wood fibers, which means that the floor needs to be refinished. On the other hand, if the water beads on the surface, you probably only need to clean and polish it.

Before you start refinishing, take the following steps to get the room ready:

• Put the furniture in another area and remove any carpeting or rugs.
• Once the floor is clear, hammer any protruding nails flat and use finishing nails to secure any loose floorboards.
• Clean the floor with a mop or vacuum.
• Ensure air vent covers are sealed to prevent sanding dust from entering your ductwork. 
• Apply plastic sheeting over doors to keep dust from migrating to the rest of the house. 
• Make sure any floor registers are taped off so your equipment won't scratch them.

Step #2: Remove Shoe Molding

You’ll want to pull up the shoe molding along the wall-floor joint before sanding the floor. Using a pry bar, remove the molding, protecting the baseboard with scrap wood. (You should not use a large crowbar or demolition bar to remove the molding, since these will damage it. If you don't have a pry bar, you can use a putty knife, but it may not work as well.) When you extract each piece, number or otherwise label it to make it easier to reinstall after you’re done refinishing the floor.

Pro Tip:If the room doesn’t have shoe base molding, either remove the regular molding or be careful when operating the sander so you don’t damage it.

Step #3: Sand Away Gouges and Discoloration

While sanding may remove scratches and stains from a hardwood floor, it may not be able to eliminate discoloration and deep gouges or discolored patches, so you’ll want to apply a coarser abrasive (around 36 grit) to a drum sander or belt sander and run it along the length of the boards, going with the grain. 

Red Label is known for offering affordable premium-quality floor sanding abrasives, including floor sanding belts and floor sanding rolls. We typically recommend using abrasives with a zirconia grain when sanding floors. Zirconia strikes a nice balance between performance and affordability. Zirconia abrasives will help speed up your work compared to aluminum oxide abrasives, but it won’t be overkill for hardwood floors like ceramic abrasives. 

Move the sander back and forth over a 3’ to 4’ length of wood flooring. Once the worst of the damage is removed, progress to a 60-grit abrasive and finish up with a finer grit (around 100). Ensure that you progress from coarse to fine grades without skipping any steps. To maintain a clean working surface, sweep and vacuum the floor before switching grits.

Step #4: Sand the Edges and Corners

Sand closet floors, bathroom floors, stairs, and edges with an orbital sander. As with the belt/drum sander referenced in the previous step, start with a coarser-grit abrasive and then move to progressively finer grades. Hand-sand small areas of flooring that cannot be reached by the orbital sander can be treated using a scraper and 80- and 100-grit sandpaper.

Step #5: Screen Sand the Floor

The flooring should be "screen-sanded" using a floor buffer equipped with a fine-grit screening pad.  This step removes minor unevenness and sanding scratches left by the drum or belt sander and orbital sander. Your DIY project can look more professional with this fine-detail work.

When you're done, sweep and vacuum the flooring thoroughly, then wipe it down with a tack cloth to remove any remaining dust, as the finish of the floor can be affected if dust and hair are still present.

Step #6: Apply the Stain

You should choose a floor stain based on the color you desire and the type of hardwood flooring in your home. Using a foam applicator pad, apply the stain in the direction of the wood grain. Work in small, manageable sections at a time.

In most cases, experts recommend removing excess stain a few minutes after application. You can do this using paper towels or clean cloths.  Before applying the finish, let the stain dry according to the directions.

Pro Tip:If you decide you don’t want to stain the flooring, apply a sanding sealer before you add the polyurethane finish.

Step #7: Apply the Finish

Now it’s time to apply the finish, which is usually water or oil-based polyurethane. A couple of things to keep in mind:

• Polyurethane finishes or lacquers that are water-based can dry quickly, posing application challenges.
• Oil-based polyurethane finishes dry more slowly, allowing for a smoother coat, but it can emit fumes during application, necessitating a respirator.

When applying the finish, follow these steps.

• Use a wool applicator in even, smooth lines, taking care to avoid drips.
• If using an oil-based finish, apply three coats. If using a water-based finish, apply four coats.
• As each coat dries, lightly sand it with 220 grit paper or steel wool #000. (Most finishes require 24 hours to dry.)
• Apply the subsequent coat after vacuuming up the dust.

Reattach the molding after the finish has dried.

Pro Tip:Place felt pads on the feet of the furniture before returning it to the room. This will prevent it from scratching the floor. It is best to avoid dragging furniture across the floor.

Red Label Abrasives: A Cut Above The Rest

Old hardwood floors can be given new life by refinishing them. When you select the right abrasives for woodworking, along with the recommended grits, you can get results that make decades-old flooring look freshly done.