Floor refinishing is labor-intensive, messy, and loud. Be sure to have top-quality dust masks or a respirator, eye protection, and ear protection. Use plastic sheeting to seal doorways and keep dust out of the rest of your house.
Buffing the Floor
For buffing a worn topcoat, you’ll need to rent a buffer and buy a gallon of polyurethane floor finish ($55-$65/gallon). It’ll cost you $75 to $125 to buff out and recoat a 15-by-15-ft. room.
Note: You can’t buff out a floor that’s been waxed or cleaned with an oil soap — a favorite product used on wood flooring. You’ll have to strip off any residue before buffing; otherwise, the new finish won’t adhere.
Test the floor in an inconspicuous area, such as a closet. Buff out the old finish and apply a new coat. If the new coat dries and sticks, you’re in business. If not, you’ll have to thoroughly clean the entire hardwood floor with ammonia and water or a commercial floor cleaning product.
Sanding and Refinishing
To sand and completely refinish a 15-by-15-ft. floor, you’ll spend $125 to $250 for the drum sander, sandpaper, wood filler, and polyurethane floor finish.
A drum sander is a heavy piece of equipment that you walk behind and guide like a lawn mower. You’ll use a series of progressively smaller grits to remove the old finish and sand the bare wood smooth.
A drum sander takes a deft touch; let it linger too long in one spot, and you’ll gouge the flooring.
An orbital sander is a smaller tool you’ll use to remove the finish and sand the wood next to walls and in corners where the drum sander can’t reach.
Dealing with Super-Hard Finishes
Some varieties of prefinished hardwood flooring are coated with super-hard finishes made with aluminum oxide compounds. These tough finishes extend the life of the flooring (and a manufacturer’s guarantee) but are difficult to remove.
Although conventional wisdom says to start with heavy sandpaper grits (40-grit) and work to progressively smaller grits, in this case you’ll want to reverse the process.
Start with a medium grit (80- or 100-grit) to begin breaking down the outer layer of the finish. Once that’s accomplished, you can move to the heavier grit to remove the remainder of the finish and flatten the floor.