Slab With Rockwool - https://buildshownetwork.com/contents/7050 There’s a first time for everything, and this is my first time specifying Rockwool Comfortboard 80 as our underslab insulation on a current project. Rockwool is a stonewool insulation that doesn’t rot, isn’t affected by water, it doesn’t sustain mold growth, and it is easy to install. We installed 2 – 2” layers underslab, and a 2” piece around the perimeter edge of the basement slab. Of course, Big Red joins in and walks us thru the