GBA Logo horizontal Facebook LinkedIn Email Pinterest Twitter Instagram YouTube Icon Navigation Search Icon Main Search Icon Video Play Icon Plus Icon Minus Icon Picture icon Hamburger Icon Close Icon Sorted

Community and Q&A

Radiant concrete slab over unheated garage.

TerlB | Posted in Energy Efficiency and Durability on

We will have a radiant concrete slab over plywood sheathing on 9 1/2″ LVL joists over an unheated garage in a climate zone 4 (Bay Area).

In a normal (non-radiant) floor situation, one would fill the joist space with insulation and put rigid underneath, then sheetrock.

Is this still necessary with the radiant slab, or would 2 layers of semi-rigid mineral wool insulation be enough to keep the radiant slab from losing heat downwards?

Is mineral wool (Roxul) the wrong way to go?

How about an air or vapor barrier, considering it’s a poured concrete slab?

GBA Prime

Join the leading community of building science experts

Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.

Replies

Log in or create an account to post an answer.

Community

Recent Questions and Replies

  • |
  • |
  • |
  • |