I installed a floating floor and it seems that water can penetrate between the seems. how could I seal these?
As to a Pergo or any type of laminate or floating floor the installation is the key. All floors have some kind of locking system which should deter most of the water from seeping through, they all have some type of repellent finish. If installed correctly the amount of water would be minimal. But, as with all laminate and floating floors water spills should be wiped immediately as replacing a single piece is virtually impossible w/o taking the whole floor up,
Buff the floor with a floor buffer that has a white pad and a 220 grit sanding screen on the bottom. Then seal the floor with a sanding sealer, then follow that up with a coating of floor finish. I suggest Bona traffic floor finish.
