Subfloor Over Insulated and Vapor Barriered Concrete Slab – Do I Need It?
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Sub floor Necessary?
New Construction, Climate Zone 6
Walkout (or daylight) basement has crushed stone, 2 inch foam boards, and vapor barrier sheet under the slab. Below grade wall of basement has sprayed black waterproof stuff and perimeter drains
If I want to use LVT vinyl tile or other floating floor, do I have to install a sub floor using any number of material — Delta FL, Dricore, OSB, Plywood, dimple mat, or other? Way over budget already, and LVT manufacturer Flooret indicates no need for any material underneath their tiles. I know the ‘feel’ would be softer with a sub floor.
Thanks
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Replies
stuartd,
No. I can't think of any vinyl tile or common floating floor system that isn't allowed to be installed over slabs.
If you want increased comfort, I would buy a flooring that has integral cushioning.
Dimple mats, etc. are remedial solutions to moisture problems for slabs that have not been properly constructed. You should be fine without them.