Sanding and varnishing a floor is a job that will take a weekend, but it’s very rewarding. It’s a dusty job too, so wear a mask and eye protection and seal off the room you’re working in to prevent the wood dust spreading throughout your home.
To start, clear the room, sweep it free of dust and, using a nail punch, knock in any nail heads well below the surface of the boards (check for any pipes or cables first). If you don’t do this, any protruding nails will rip the sandpaper to pieces. Secure any loose floorboards.
Hire a drum sander (it looks a little like a vacuum cleaner and rental costs around £50 per day) and coarse grit paper, and work in diagonal lines that overlap slightly across the room. Repeat the process but go diagonally at right angles to your first pass. This takes out any unevenness in the boards.
Once the floor surface is flat and level, use a medium-grade, then fine-grade paper to work up and down the lengths of the boards to get a smooth finish.
As the drum sander won’t get close to the skirting boards, use an edge or hand-sander to do the extremities – these cost around £35 per day to hire. Use coarse, medium, then fine sandpapers, and keep the sander moving at all times or it can damage the boards.
Sweep to remove the dust, and wipe the boards with a mop dampened with white spirit. Allow this to evaporate and keep the room well ventilated, then apply three coats of floor varnish for a hardwearing finish.
If you live in a flat, check your lease first, as it may be a breach of the terms not to have carpets covering your floors. Floorboards are noisier than carpet and could cause disturbance to your neighbours.