It comes with an attached underlayment.
What are the pitfalls of installing this? What should I be aware of? I will be installing this in the kitchen. Can I put heavy furniture on laminate wood flooring? Can I put regrigerator on it? How about my IKEA kitchen base-cabinets that stand on plastic legs? Will that allow the floor to "float" and expand and contract? Or am I looking at gaps in joints 1 year away?