Refinishing Hardwood Floors

For May’s editorial we’re going to go into a bit of depth about refinishing floors. As the DIY season is coming around, many people will look into various remodel projects and other ways to spruce up their home. Many times, giving the current hardwood floor a face lift is a great way to freshen up a room.
Refinish or Re-screen?
Before beginning a refinishing project, it is important to know whether or not your floor needs to be refinished or re-screened. Re-screening is a process which involves removing the top layer of finish, and then applying new layers of finish over the top of the remaining finish coats. Typically most floors which receive any work only need a re-screening, as a majority of scratches or surfaces marks are only in the finish and have not damaged the wood itself.
In the case where gouges have occurred, or very deep dents which have effected the wood, then this is a more likely candidate for an actual refinish job. You may also decide to refinish a floor if you wish to change or remove the stain currently on your floor.
It is important to note that most pre-finished floors have between 5 and 8 coats of finish on them normally, this means that once you refinish them, you will never have a finish layer that is quite as long standing as the initial finish, as most site applied finishes are 2-3 coats. Also, most pre-finished floor warranties will be void as soon as you refinish or re-screen them, so keep this in mind before deciding to proceed with any refinish or re-screen work.
Re-screening Process
Re-screening a floor is far more simple than the refinish process. You will need to buff the floor using a 220 grit sand paper or screen to abrade the surface of the finish enough to allow for new finish to adhere to the floor. Before you begin buffing, it is highly advised to rub two piece of sand paper against each other to slightly dull them before going to work on your floor, this will help prevent swirls in the finish, layer. Using a buffing machine with 220 grit screens are heavily suggested here. Once you have finished abrading the floor, you will then want to ensure all dust is cleaned up. Any debris or dust left on the floor can cause major problems with the finish when it is applied.
Remember, it is best to apply multiple thin coats of finish, lightly buffing between each coat rather than a few thick coats of finish. If your previous finish is an aluminum oxide finish it can be very difficult to adhere new finis to the aluminum oxide – so use a product like Bona Prep and any adhesion worries should be eliminated.
Refinish Process
Refinishing is a bit more work than re-screening, but the methodology is the same. You will want to rent a floor sander and get a good range of screens, typically 36 or 40 grit, 60 grit, 80 grit and 100 or 120 grit. Most refinish jobs will only use 3 screens, but if you want to be a bit more thorough, use the 4 listed.
Before you begin sanding make sure to mask off all of the door ways (painters plastic or visqueen taped up along all door ways to corridors or other rooms). Turn off any heating or air conditioning circulation systems to prevent dust from getting pushed throughout the house. Also ensure you wear proper eye protection and a dust mask or respirator. Sanding a floor will produce a lot of dust and you do not want to breath this in nor have clean it out of other rooms. At this point lightly use the sand paper/screens against each other or some concrete, much like you do for screening, before you begin sanding.
Start by attaching the 40 grit screen to your floor sander (typically a drum sander) then evenly sand your floor. Make sure that you are not moving cross-grain with your flooring as this can mar the floor. Always keep the sander moving while it is active to prevent swirl marks from occurring. Once you have sanded the entire floor, make sure to use an edger if your sander can not cover the edges of the floor, then vacuum up any remainder dust, then move up to the next screen (60 or 80) and repeat your sanding and vacuuming process. Once you have finished with this screen, simply repeat the process until you have used your final screen, which is either 100 or 120 grit. If you are going for a natural finish, finish with 100 grit, if you are going to apply a stain to your floor, use 120 grit be fore applying the stain.
Once this is finished, apply sealant and stain if you plan on staining the floor, then apply your first coat of finish. Allow the finish to cure per its instructions then buff with a 220 grit screen. Buffing helps to lightly abrade the finish so that the subsequent layer of finish can properly adhere, preventing flaking and dulled or milky looking finishes. After buffing, apply the next layer of finish and repeat the process until you have applied all of your finish coats. Do not buff the final layer of finish.