Can you install engineered hardwood over engineered hardwood?
Beside this, do I need underlayment for engineered hardwood flooring?
If you're installing laminate or engineered flooring that snaps together and floats over the subfloor without nails, you need underlayment even more. Besides all the other benefits, underlay helps support a floating floor. You may find that the flooring still requires a vapor barrier.
Similarly, you may ask, is it better to glue or float an engineered wood floor?
If you are trying to decide between the two, then for engineered wood flooring floating is usually the best option as you can install it quickly and don't have to worry about which glue to use and how long to wait for it to dry. If you are installing hardwood flooring then using glue may give you a more stable result.
Yes! Using floating floors allows you to have the beauty of hardwood in moisture-prone basements, where a solid wood floor is not recommended. In a floating installation with engineered wood, boards respond to humidity and temperature changes as a unit, expanding toward the walls or contracting away.