Always read the flooring manufacturers recommendations and instructions before installing the underlayment.
How to lay vapor barrier on concrete under laminate flooring.
Before rolling out the underlayment be sure to sweep vacuum and remove all debris on the substructure.
If your concrete passes the moisture test then plastic sheeting at least 6 mils thick will prevent moisture from getting into your laminate flooring.
How to install vapor barrier on concrete floor under laminate flooring.
This 3 in 1 underlayment can be used under any laminate flooring to allow your floor to float and create a moisture barrier.
Vapor 3 in 1 underlayment silver 100 sq ft roll.
Where plastic sheets must be joined overlap the sheets by several inches and use strong vinyl tape to secure them.