What is a ballpark per square foot estimate to have oak floors refinished?
You’ll have to check around your own area, but I can tell you what I charge. I will sand a floor 3 times (coarse, medium and fine grit sandpaper) down to 100 grit, AND do the edges 3 times, the last edging done with a vibrator sander to remove any swirly edger scratches. Then I vacuum the floor really well, and apply a thin coat of oil modified polyurethane (Fabulon brand heavy duty). I let that coat dry for about 24 hours and screen it and clean it with solvent, and then I BRUSH BY HAND the second coat. 48 hours later I can usually do the same prep and apply the third coat. All this will cost $2 per square foot.
If you want to use a water based finish, I would use 4 coats of the Dura Seal 1000 water based finish( see article in Floored News). Oh, with one more fine sanding of the wood. the first coat is the acrylic sealer and then 3 top coats, buffing and cleaning well between all coats. All this would cost $3.50 pr square foot. All these prices are based on 300 feet and up.
That said, you will find a variety of floor sanding methods and finishing methods. But do try to find the best method. please read my hiring article in the Hardwood Authority section of this site.
Skipping steps and using cheap lacquer sealer are not a good way to save money. Read about this in the Lacquer floor fires article in the Floored News section of this site. I hear you can still get cheap and dangerous floor jobs done like these guys did for about 75 cents per ft.
As always your Most humble servant, Joseph, the Wood Floor Doctor.