My laminate (Pergo-like) flooring has developed 1/4" gaps on each end of a plank. I dont think its water damage - I use an appropriate cleaner. Could this be because the planks might have not been seasoned,or no underlayment? I thought I remembered him using underlayment. Its in a 1/2 basement and a dry cold climate. Is there some reasonable aesthetic solution - (fill in cracks with what?) Is it possible to put coats of polyurethane on top if I ever decided to replace the floor? THANKS!