The bottom surface, often called a backer or a balancing layer, seals the bottom of the flooring and balances the surface tension of the top to help ensure dimensional stability. Warranties range from about five years to 16 years. Warranties for vinyl flooring typically range from about three years to ten years. Components are sized to allow easy mixing and matching. Manufacturers even sell laminate moldings and transition strip.
Laminate flooring is edge-glued over a foam underlayment to form a floating floor.
An expansion gap, hidden by baseboards and other moldings, surrounds the flooring perimeter. This system allows the floor to act as a unit that can move seasonally without opening visible gaps. The relatively thin flooring also can be installed over existing vinyl, linoleum, ceramic tile and wood flooring without significantly raising the floor level. Excessive moisture can penetrate and damage the wood-base core of laminate flooring. Most manufacturers strongly discourage installation in full bathrooms.