Professional floor sanding: How to professionally sand a wooden floor

This section tells you all about how to professionally sand your floor:

Machine choice

To sand a floor professionally starts with professional floor sanding machines. Add to this some patience, an eye for detail and some quality floor seal and you'll be on your way to creating a stunning wooden floor.

Bristol Floor Sanding uses the latest dust-free sanding technology. Highly efficient dust extraction systems on these machines results in around 3-5% dust.

Spend a bit of time thinking about the floor that you are about to create... you're going to be living with this floor for a number of years so it pays to get the job done properly the first time around. Floors which have been sanded badly can be very costly to repair!

For more information about machines click here .

Some questions you might like to consider

  • What is the overall look you want to create? Strong, or light, smooth, or soft.
  • Is there a particular "feel" you want to create in the room?
  • What colour should the room be?
  • Will it match your existing decorations and furnishings?
  • How much natural light is there?
  • Do you want a uniform finish or are you worried about draughts? Filling the gaps between the floor boards might be an option.
  • What type of finish do you like? Matt? Glossy? Satin? Or would you rather have a natural, environmentally friendly option?

Sanding a wooden floor - choice of grit

Having thought about the effect you want to create, prepared your floor and gathered the right professional equipment, you are ready start sanding.

Sanding abrasive comes in different grits, or different levels of coarseness:

  • 24 grit - very coarse
  • 40 grit - medium coarse
  • 80 grit - medium
  • 100 grit - fine
  • 120 grit - very fine

If your floor has never been sanded before, you will need to start with a 24 grit to take off the surface and level the floor. You will then move through the rest of the grits in sequence, essentially to remove the marks you made from cutting off the surface with the 24 grit.

24 grit

  • initially to level the boards and create a true and even surface on which to continue sanding
  • to remove deep dents and marks
  • to remove previous seals or oils

Start by working at a 45 degree angle to the grain to level the boards. You may need to turn and work on the opposite 45 degree angle too if the boards are very uneven. Once boards are level you can start working up and down in line with the grain to remove deep scratching.

40 grit

  • initially if boards are already true and even
  • to remove deep marks

If you have not worked with 24 grit previously, you may start by working at 45 degree angles to the grain. Otherwise, simply run up and down the wood with the grain.

80 grit

  • to begin the polishing the wood
  • to remove marks created by 40 grit

This is when the real beauty of the wood will begin to be revealed. As the deeper marks are removed, the grain will begin to shine. Work in direction of the grain.

After this stage of sanding you may gap fill your floor.

100 grit

  • to further polish wood
  • to remove marks created by 80 grit

Work over the floor more quickly as you get to the finer grits. Keep working in direction of the grain until the wood shows no scratched or dents.

120 grit

  • to finish before sealing
  • to remove any final blemishes

This is the final grit that is used to finish the sanding process. By this stage, the floor should be blemish free and ready to polish and seal.

You may colour or stain the floor after the floor has been polished.

Edging - clean lines

Warning! Never force the edger to cut deeper into the wood. If the edger is not sanding cleaner or efficiently change to fresh abrasive.

Since the big belt sander, used to sand the boards, doesn't reach tight into the edges of the room, you will need to use the edge sander to go around the edges.

The edge sander is a smaller machine that has a fast, spinning disc of abrasive which is guided right into the edges of the floor.

You work with this machine in a similar manner to the belt sander. You will start with 24 grit and work progressively up to 120 grit, removing all marks made by the previous abrasive as you step up a grit.

Hint: you may find it best to work with the belt sander and the edge sanding machine alternatively in order to avoid leaving marks where one or other of the machines has been working. Ie. work with 24 grit on the belt sander, then 24 grit on the edger, then 40 grit on the belt sander and 40 grit on the edger and so on.

Polishing and vacuuming

Having completed the sanding, you are ready to finish the floor. Ideally this is done with a Trio , although a Buffer will also work well.

Using either a Trio or a Buffer, work quickly across the floor with a fine grit, 120 grit or finer. This will remove all final imperfections on the wood and ensure that your floor looks fantastic and accepts the seal fully.

If you are working with a Buffer, you may create some dust since there is no extraction system. Be sure to work quickly and avoid revisiting the same area of the floor twice since this will stir up the dust.

Having polished the floor in this way take your vacuum and THOROUGHLY clean the floor to remove all dust.

Your floor is now ready to colour / seal.