How to sand a floor

Summary: Learn how to sand a wood floor, prepare the floor, using a drum sander, using an edging sander and using a corner sander.

Waxed, varnished or stained floorboards can be an attractive feature. But unless you are fortunate enough to be working with new floorboards you will probably have to sand the boards to remove the old finish and smooth any rough areas. The tool used to do this is an electric sander. To reach all parts of the floor you will need two or possibly three sanders: a heavy-duty drum sander, an edging sander and a corner sander. Drum sanders and edging sanders can be hired from tool hire companies. Corner sanders are smaller tools and relatively inexpensive. You will also need to use different grades of sandpaper, starting with heavy-duty sandpaper and reducing the coarseness as you progress.

Preparation

  • Remove any polish with white spirit.
  • Check the floor for any loose floorboards (see Floor Problems).
  • Wearing work gloves carefully run your hands over the surface of the floorboards to find any protruding nail heads. These should be punched into the board to prevent damage to the sander.
  • Sanding is a dirty job that produces a great deal of dust. To prevent the dust spreading, close the doors of the room you are working in and open the windows. Stick tape around the doorframe and stuff rags under the door.
  • Always wear protective goggles, ear defenders and a respiratory mask.

Stage 1: The drum sander

  • To sand most of the floor you will use a drum sander. Before connecting the sander to the mains, unscrew the bar that holds the paper in place and feed in a new sheet so that it lies taut around the drum. Re-position the bar and screw it down tightly.
  • Plug the machine in and tilting it back to lift the drum off the floor, switch the machine on.
  • Lower the drum to the floor and slowly move diagonally across the floor.
  • When you have covered the whole floor, replace the sheet of sandpaper with a less coarse paper and sand the floor diagonally again but in the opposite direction. Always move the machine forwards – never drag it backwards when the drum is rotating against the floor.
  • When changing the sheet of sandpaper, always remember to unplug the machine.
  • Then using a finer grade of sandpaper, start at one end of the room and sand the floorboards in the direction of the grain.

Stage 2: The edging sander

The drum sander does not work effectively at the edges of the room, so for these areas you will need to use an edging sander.

  • Ensure the sander is not plugged in to the mains. The sandpaper for an edging sander comes in disc form that is held against a wheel by a retaining bolt. Undo the retaining bolt with the key provided and fit a new disc of sandpaper. With the new sandpaper in place screw down the bolt until it is well below the surface of the wheel.
  • Holding the sander firmly, move it around the edges of the room being careful not to damage the skirting boards and any electrical cables or pipework.

Stage 3: The corner sander

A corner sander has a pointed sanding pad and is designed to sand floorboards in the corners of rooms where the drum and edging sanders cannot reach.

  • To load, simply rip off the old sandpaper and press on a new sheet aligning it to the sander’s pad.
  • Use in the corners and other awkward areas such as under radiators.
  • Use a broom and vacuum cleaner to remove any dust from the floor that was not collected in the dust bags. Finally, wipe the floor over with a damp sponge or mop and leave to dry.
  • You can now apply your chosen finish (see wood floor finishes).

Tools needed

  • Nail punch
  • Drum sander
  • Edging sander
  • Corner sander
  • Safety goggles
  • Ear defenders
  • Disposable face mask

Materials needed

  • Sandpaper
  • Nail punch

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