• Refinishing hardwoor floors is a three- to four-day project that any homeowner can tackle.floor cleaning #5 image by stassad from Fotolia.com
  
  Most medium--priced homes built before the mid 1960s were fitted with hardwood floors and later covered with carpeting. Now that hardwood flooring is back in style, many homeowners wish to restore their floors to enjoy the beauty and convenience of hardwood. However, professional floor finishing is expensive. If you decide to tackle the project yourself, prepare for three to four days of hard work.
  
  

Preparation

• Clear the room of everything that's not nailed down, and inspect the floor for damage or discoloration. Remove the skirting boards. If your wish to retain the old wall skirting and shoe molding, run a sharp utility knife along the upper edge of the boards to cut through the layer of paint separating the wood from the walls. Use two or three pry bars inserted as close to fixing nails as possible, and carefully pry the skirting away in sections. Look for shiny exposed nail heads on the floor. Sink all loose nails into the wood with a nail set and hammer. Fill the holes with a suitable filler once you've sanded the floor and established the color of the underlying wood. Check the floor for badly damaged, loose or squeaky floorboards. Secure loose planks with slightly larger nails hammered in at an angle and set below the surface. Remove any badly damaged boards. Cut the surface of one or two planks down with a carpenter's plane to establish the color of the wood before buying and fitting replacement boards.
  
  

Equipment

• Rent a good floor sander, and ask for a demonstration before choosing the type. Drum sanders are the most efficient; however, they are noisy and somewhat tricky to handle. They can also cut a gouge into the flooring in seconds if the machine is not constantly on the move. Three-pad orbital sanders are quieter, more forgiving and easier to use, but they take up more time and require a few extra passes over the floor. The orbital sander is the logical tool of choice for the first-time floor finisher. You'll also need to rent a powerful shop-vac if you don't already own one. Pick up a rotary hand edge-sander, together with a supply of abrasives while you're at the rental store.
  
  

Sanding

• Open all the windows for ventilation. Mount a good out-blowing box fan in one or two openings. Drape heavy plastic sheeting over the doors to contain as much sanding dust as possible. Wear soft-soled sneakers, heavy workman's gloves, ear muffs, safety goggles and a good charcoal-filtered respirator during the project. Start with 36-grit sandpaper. Position the orbital floor sander in the farthest corner from the door. Start the sander. Go with the grain, and keep the machine moving in a sweeping side-to-side motion as you work your way along the length of the room. Overlap the sanding edges on the return pass. Go over the floor as many times as necessary until the cupped middle sections of every floor board are sanded down level with the outer edges. When the entire floor is the same color, use the hand finishing sander to go over the edges close to the walls and door openings. Fill all nail holes with a suitable wood filler. Use a powerful floor-vac to remove all dust and abrasive particles between each sandpaper grade change. Repeat the whole operation with 50-grit and then 80-grit sandpaper to smooth out swirl marks and scratches left by the previously used coarser sandpaper. Use a handheld orbital sander to clean up the edges and door openings. When the floor is an even color without blotches or visible scratches, you're finished sanding.
  
  

Varnish Preparation

• Vacuum the floor twice with the shop-vac. Scrub the soles of your sneakers. Soak a rag in denatured alcohol, and wrap it around a long-handled floor mop before going over the entire floor. Finish up with a microfiber tack cloth to remove all traces of loose dust from the floor.
  
  

Applying Urethane

• Two types of finishes are suitable for wooden floors: Oil-modified urethane (polyurethane), and water-based urethane. Oil-based polyurethane was the preferred finish for most professionals until fairly recently. However, extended drying time is called for between coats, maintaining a wet edge during application is essential, and the material is highly toxic. Water-based urethane, on the other hand, is less toxic, dries quicker, is more durable and you can clean brushes and applicators with soap and water. Consequently, water-based urethane is recommended for the first-time floor finisher. Use a long-handled weighted foam applicator. Apply the first coat by back-brushing with the grain in 3- to 4-foot strips along the length of the floor. Allow 24 hours curing time. The first coat tends to raise wood fibers on the surface of the floor. Scuff sand the first coat with 120-grit sandpaper fitted to a pole sander. Finish the edges and opening with an orbital sander fitted with 120-grit sandpaper. Change the sandpaper often, and go over the floor until the gloss is broken. If you prefer, use the orbital floor sander fitted with 150-grit sandpaper. Wipe the entire floor with a cloth soaked in denatured alcohol, and finish by wiping with a microfiber tack cloth. Apply the second coat as described above. Refer to the instructions on the back of the paint can, and allow adequate drying time (usually about 3 hours). Repeat with the third and fourth coat. Allow 24 hours for the finish to cure before replacing the skirting boards and moving furniture into the room.