How to Sand a Wooden Floor

There are three main steps to restoring wooden floors:

Part 1 of our guide to sanding floorboards takes you through preparation. Here, we walk you through sanding wooden floors. This includes tools and materials you’ll need and the steps to follow.

Sanding wooden floors DIY guide

Materials List for Sanding Wooden Floors

Sanding wooden floors can be messy and gruelling. However, with the right tools and by following best practices, you can get a beautiful finish. Indeed, restoring floorboards and other wood floors, such as parquet and herringbone, is some of the most rewarding DIY you can tackle. So what do you need to get this done? Check out our materials list:

  • Work clothes. This will be a dirty job. So, choose old clothes and wear them only in the work area.
  • Safety equipment. You’ll be exposed to a lot of dust. Therefore, you’ll want to wear a HEPA-filter respirator mask, safety goggles and gloves. Also, sanders can be loud, so ear defenders are a wise choice. Finally, you may find knee pads are helpful as you’ll be up and down a lot.
  • Tools for removing nails. This can include a claw hammer, staple and tack lifter, pinchers, drop hammer nail puller, and diagonal cutting pliers. These items are important for the preparation steps however, we list them here for completeness.
  • Clean-up supplies. We recommend tidying with a hoover at the end of each day. Once the job is done, plan on dusting all skirtings and crevices where dust can settle. Completely clearing the room during the preparation stage will save you time and hassle there.
  • Drum sander, edge sander and sandpaper. Plan on hiring a drum sander, preferably a dustless sander, and an edge sander. You’ll also need coarse, medium and fine grit paper.

Okay! You’ve got your gear together. Now, let’s start sanding wooden floors!

Steps for Sanding Wooden Floors

Firstly, you’ll need to hire sanders from a local specialist. A drum sander will do the main area of the floor, while an edge sander takes care of the sides and corners. Likewise, you’ll need enough abrasive sheets to sand the entire floor. Now we’re ready to move on.

1. Set Up the Sander

Before you being sanding your wooden floors, you’ll need to set up your drum sander. To do so, load the abrasive sheets into the drum sander making sure the sheets are tight around the drum. This can be difficult for first-timers. So if you are unsure, be sure to ask the hire shop to show you how to do this correctly.

In terms of the grit, the state of your floors determines the grade of abrasive you start with. Perhaps starting with a 60 or 80 grit. Use these coarser grits to sand off the old finish. Then, use a medium grit to smooth out the surface. Finally, end with a 120 grit. This fine grit will clear imperfections and prepare your floors for sealing and sanding. Lastly, be sure to replace your sanding disks as they wear out.

2. Begin Sanding

If your floor is uneven or very rough you will need to sand diagonally across the floor. By aligning the sander at 35-40 degrees to the grain of the wood, you speed up the levelling process. However, if your floor is already level then diagonal sanding may not be required.

So, your drum sander is loader with coarse grit paper. Perfect! Begin sanding by putting on your mask, goggles and ear defenders. Now you’re ready to switch that sander on! When doing so, start the sander with the drum off the floor.

Now, each time you sand a length of your room it is called a ‘pass’. When an area has received two passes it is called a run. So, starting on the left-hand side of the room and going with the grain of the wood (or in a diagonal as appropriate) walk forward and ease the drum to the floor. As you near the end of the room – ie the end of your pass – gradually raise the drum off the floor. Now, turn around and repeat over the same area. At the end of this pass, you have completed one rung. Now, move the machine across approximately 7cm to the right so that the machine overlays 2/3 of the first run. Repeat until you complete the entire room.

Sanding wooden floors diagonal
Begin sanding wooden floors using coarse grit and diagonal passes

2. Edge Sanding

Once you’ve run the drum sanding over the entire floor, the main work of sanding your wooden floors is done. However, you do need to deal with the perimeter of the room where the drum sander could not reach. This is where your edge sander comes in. Beginning with coarse grit, work around the outer edge of your room. Aim to match the edge to the main body of the room. When you’ve done so you can move to finer grits.

3. Coarse to Fine Grits

After removing the old finish with coarse grit, you’ll need to smooth out the floor. To do so use a medium and then a fine grit on your drum and edge sander. That is, in our own floor sanding in Essex, we typically fully sand a floor with grits. While laborious, this is the only way to get a good-looking and long-lasting finish.

NOTE: these passes should be done with the grain of your floors. Only the diagonal cut with the coarse grit does not follow the grain. So, when working with medium or fine paper, go with the grain of your floors.

4. Gap Fill

If you are working with floorboards, you may want to fill gaps between them. This is the time to do so. You can do this in two different ways:

For mass fill, mix 80 grit dust from your sander with resin. Smooth this into the gaps. Once dry, sand the floor one final time. This process should only be used on gaps less than 5mm.

Alternatively, use pine slivers to fill gaps and draught-proof your floors. In this case, slivers are first hammered into gaps with a rubber mallet. Then the floor is sanded a final time to level and prepare for finishing.

5. Clean Up

The last step is to clean up. A thorough hoovering will remove dust and debris. This is essential before moving to the last stage of the process namely stain and seal.

Sanding wooden floors DIY Guide 2019
It can be done!

Floor Sanding Fundamentals

A couple of key things to keep in mind when sanding wooden floors:

  • Always sand with the grain of the wood (the exception being a diagonal cut to level your floor).
  • Be sure to ease the drum sander down, too fast and you will gouge out parts of the floor.
  • Parquet and original wood strip floors can be sanded HOWEVER you need to take extra care as the wood is thinner than when sanding floorboards.

Professional Floor Sanding

We hope our guide has helped you to build the confidence to sand your floors. However, we know this is a big, messy, time-consuming job. So, if you’re still feeling unsure, find a pro. Simply Sanding serves Essex, London and the Southeast. Contact us today for a free, no-obligation quote.