A Vapor Barrier Under Laminate Floor Reduces Damage laminate over concrete no vapor barierInterior Vapor Retarder Over Concrete Subfloor When a laminate floor is installed over a concrete subfloor a moisture barrier must be used. Most every laminate manufacturer will require a vapor barrier under laminate flooring.

Not sure, check the manufacturers installation guide for the flooring that you are installing.

Most laminate and real wood floors are laid by dry-clipping boards together. Clipping mechanisms vary, but the principles are the same. Whether you need a vapor barrier or underlay will depend on the type of floor. If in doubt, install one.

Where possible, lay flooring before installing baseboards or door casings so that they can cover the expansion gap. Wooden flooring needs to acclimatize for two or three days before being laid. Open packs and lay out the boards. Some flooring will need to be oiled after installation.

nstall a plastic vapor barrier: If your concrete passes the moisture test, then plastic sheeting at least 6 mils thick will prevent moisture from getting into your laminate flooring. Where plastic sheets must be joined, overlap the sheets by several inches, and use strong vinyl tape to secure them.

The vapor barrier will also prevent radon gas from penetrating the slab, an added benefit.