Insulating addition over unheated garage
I'm a homeowner tackling an addition on my own (so far). I'm located in zone 6 (Twin Cities, MN). I searched for this topic and most of the answers had to do with warmer zones (<4) and I'm unsure of the approach for my (cold) area.
The project is an addition over an existing garage. The garage is unheated and built with 22" deep web trusses, 2X6 walls. Part of the house overhangs the garage and is already insulated with fiberglass batt only. Yes the floor over that space is cold.
The new addition will adjoin the existing space and I want to have a consistent insulation strategy for the entire garage ceiling.The advice so far,
1) closed-cell foam - prohibitively expensive
2) fiberglass batt - simplest installation, lowest cost, seems to be the lowest performer as well
3) blown-in cellulose/fiberglass - I have no experience with blown-in
4) have considered 1.5" rigid against floor sheating, then fill batt (almost like the flash and batt)
The walls of the addition - I'm planning traditional R-19 fiberglass batt.
Looking for advice.
Posted Feb 3, 2011 9:56 AM ET
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