West asked:

It really just seems stupid if I’m looking to put a new shine on a floor. Can’t I just clean the floors good and lay down a thinned bit of poly?

Reply:

its always a good idea to scuff the floor.

think about it, if you were to take some say, 220grit sandpaper and scuff down the entire floor it would do wonders. it would remove almost all imprefections the current topcoat has got over the years. bugs, dog poop, mud, food and so on. its not a MUST, but highly advised. also, it helps the new coat of finish have something to grab. if you topcoat directly over the current finish, the new coat doesnt really have anything to “grab on” to if that makes any sense?

also, you should be sure to use the correct type of finish, make sure there will not be a chemicle reaction with your current topcoat and the new stuff you plan on putting down. if the two finishes dont go good together you can have REAL problems and be forced to strip the entire place down to raw wood! if youre unshure of this, i would advise using some type of sealer or blocker to seperate the currect finish and your new finish.

BE SURE TO clean off the floor so its spotless before you top coat. any type of sawdust, sand, hair or anything like that buy cheap drugs will show up badly in the new finish.

good luck!