[villagetinker]

I had very poor results with the 511 product, especially in the kitchen. When I called them they stated "in heavy traffic areas this needs to be reapplied EVERY 2 YEARS", I strongly suggest staying away from this product. As noted above, you should NOT reseal the floor. If you were to do this you may end up with a very slippery surface, and if the sealer does not grip well it may peel off. You do need to seal the grout, unless you got lucky and the original grout was the sealed type. I have used a product called grout shield which is similar to paint. You order it based on your grout color (get this from home warranty). This takes time to apply, but a much better product than 511, also it matched the original grout so well I actually missed a few areas that showed up when we mopped the floors.