Cellulose vs. fiberglass batt cavity insulation with rigid foam exterior in zone 5 central NJ
I'm looking at cavity insulation options for a new 2200SF house that will have 1-1/2" polyiso on exterior walls and 3" on the roof. Cavity insulation prices are coming in at roughly $4500 for fiberglass batt (R21 walls/R38 roof) and about 3 times that for cellulose. While the benefits of cellulose have been well covered on this blog, I'm having trouble justifying the added cost for cellulose and wonder to what extent the short comings of fiberglass are mitigated by the addition of the foam on the exterior. In short, does fiberglass batt cavity insulation perform better with rigid exterior insulation?
Posted Wed, 12/12/2012 - 15:11
Other Questions in Energy efficiency and durability
Any information about the efficiency & cost of direct Solar Hot Water systems versus using Heat Pump Water Heater and PV panels to power it?