I've perused the threads on this and still unsure. Last week I had 7mm laminate click fit installed in a lounge diner. The fitter rolled a foil backed underlay over the bare floor boards. I'm thinking of having a go at the hall myself. Wooden 80yr old floor boards. I've bought some 12mm Laminate on offer from Wickes. Do I need to level the floor as the fitter didn't bother in the lounge? He also looked at the kitchen and thought he could lay directly over the old stick on vinyl tiles, go to the wall and put the washing machine, fridge and freezer on top. Is this ok? Any advice on correct underlay appreciated. Its a jungle out there with price and choice. Thanks.