I have been recently contacted to refinish an engineered prefinished oak floor. I have never dealt with this type of floor. The concern I have is two fold. First is that it has a thin wear surface, so sanding is out of the question. Second is the type of finish to top coat the floor with.

I believe the original finish is water base possibility aluminum oxide; it is about ten years old. It suffers from scratches but no gouging and some graying in a couple of high traffic areas. My plan is to screening and recoating. The new home owner prefers the look of an oil base finish, I am not sure that can be applied over this type of prefinished floor so I guess my main concern is about the finish to use.

Thank You

After properly prepping the surface, You may use an OMU (oil modified urethane). With a 10 yr. old floor, it may or may not have an "enhanced" urethane finish, meaning a finish that contains aluminum oxide, ceramic or titanium. An OMU will generally not perform as well as a quality two-component waterborne urethane like Bona's Traffic or Basic's Street Shoe. And most waterbornes are superior in bonding properties. But your biggest concern should be has the existing finish been "contaminated" by improper cleaning products. If so, any recoat could fail to bond, even with screening and a through cleaning. Also, those "grey" areas will probably not get much better. FYI, it is possible to resand thin veneered floors if they are really flat without much overwood. One needs to choose the paper (grit) carefully. I will typically just edge it out first with 100 then drum it with 100, sanding just enough to remove the finish and most of the stain color. Then stain and finish in the typical manner. However, if you are not sure you have the ability to pull this off, then either walk away, talk them into a new floor or proceed with caution on your recoat plan. Good luck.