The little cabin has minimal wall insulation, no floor insulation at the main area. I'll verify any insulation if it exists in the Northern portion when I get through the floor sheathing. The ceiling in the main area had R-30 batts in the ceiling. The ceiling in the North portion had R-11 at best.
So I have registered the project with Energy Smart Colorado. This will allow us to qualify for rebates and low interest loans for the thermal upgrades that will be made. We start with a blower door test. This will be interesting...it is like testing a fine mesh strainer for air tightness.
The good news: I'll be able to demonstrate significant thermal improvement when complete!
A remodel like this - as all are - is the balance between cost, thermal improvement and design. Us architect folk walk that balance beam every day of our lives. It's fun!
My strategy for thermal improvement is rigid insulation. I believe, short of in-situ sprayed poly iso foam (expensive) - the rigid insulation strategy will offer the most efficient thermal performance. Why?...I have 2 x 6 floor joists, 2 x 4 and 2 x 6 roof joists at 24" oc and I don't want wall furring any greater than 2 x 4's for space reclamation and use. At R-5 per inch I can get an R-27+ floor with 5-1/2" of rigid and the same for the roof without re-building the structure of either assembly. Simple.
My initial thermal calculations - if they are correct - using conservative heating degree day numbers for this region (Eagle County Airport and NOAA weather data) indicate with the revised thermal envelope I should be able to heat the cabin with $50 worth of gas per year. I'm going to verify the calculations.
So the technical evaluation of the envelope begins. I am modeling the performance using hand calculations and will attempt to translate those calculations into a zEPI (Zero Energy Performance Index) number soon.
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