Hi, I am currently building a home. Unfortunately, my contractor did not install radiant heat barrier roof decking. We have just completed the framing and roofing stage, so no interior work has been done. My house is 2 stories, 3800 sq. ft., with a lot of attic space, some of which I will finish out into additional living space in the future. I would like your opinion as to what to do:
- rip the current roof decking off and reinstall with integrated radiant heat decking material,
2. install radiant heat foil under the roof rafters with blown-in cellulose attic floor insulation,
3. use an IRCC rated reflective spray paint over rafters and decking with: a) blown-in cellulose attic floor insulation only, b) foam insulation in the rafters after the reflective paint has been applied,
4. no radiant heat barrier of any kind.
My house is in Oklahoma City where we have several days of sub-freezing temps in the winter, snow and ice, and 2-3 months of above 90-degree temps in the summer with the possibility of 15 days above 100. A quick reply would sure be appreciated.
I would recommend your second option — install a radiant barrier on the face of the roof rafters and your choice of mass insulation on the floor. That would give you the most cost effective and thermally effective solution.