How do I level my floor so I can install laminate?

Get as close to level as you can with wood, then use a leveling mix.

Lisa,

It depends on how bad it is. There is a difference between level and flat. Your floors do not have to be level, but they do need to be flat. Are you considering removing all flooring and sub flooring down to the joists when you say the floors are shot? How many layers of flooring do you have? If you strip down to the joists, you can make it level as well as flat if that is important to you. If you are not going to that extreme, then strip back to the existing subfloor. Is it plywood or planks, as many old houses have? You can use a straight edge, like a 4 foot level, to see how uneven the floor is and where you might have low and high spots. If the subfloor is 3/4" or thicker plywood, you might be able to get away using leveling compound to make the floor flat, putting down the manufacturer's suggested underlayment, and then installing your laminate. If it is planks or thinner plywood, you may need to add another layer of plywood sub flooring to provide a flat and stable enough surface to install your laminate over.

Hi Lisa, you can sand down the high spots as much as possible, then use this type of compound to level

https://www.youtube.com/watch?v=lPh7lFyY7qI