Dear List-
I am researching the EPAct ?179D Energy Efficient Commercial Buildings Tax
Deduction, specifically the segment for $.60 per square foot building floor
area for building envelopes that contribute to %50 better than ASHRAE 2001.
The main question I am attempting to figure out is if Phase Change
Materials could be used in conjunction with ASHRAE 90.1 2007 or 2010
prescriptive insulation and fenestration requirements (or better) to
achieve the tax credit. The projects that this would apply to are currently
going for LEED but may not be going for EPAct. I am trying to figure out
how the envelope contribution to the %50 better than ASHRAE 2001
requirement is segmented to understand if these projects could be
applicable for the credit due to the advanced Phase Change Material
envelopes.

I understand that the procedure to follow is ASHRAE 90.1 2004, and the
baseline to be 50% above is ASHRAE 90.1 2001.

- Question 1: Is the calculation for %50 reduction similar to the LEED
% of cost approach or if it is a % of energy basis?

The part I do not know is the multipliers to segment the envelope only
portion and associated modeling procedures. If this is based on minimum R
values and maximum U values than our product would not contribute to the
%50, while if it is based on %50 energy reduction from the baseline
envelope energy use than phase change materials could contribute to the
credit and receive the $.60 per square foot building area.

- Question 2: How is the envelope segmented from the HVAC and lighting
systems when applying for envelope only EPAct?

I have a budget to buy any required literature, but do not want to misuse
funds by buying unnecessary publications.

- Question 3: Should I get ASHRAE 90.1 2001 and ASHRAE 90.1 2004, or can
I find this info in the ASHRAE 2010 version I already own?
- Question 4: Is there any other reference materials that are advised
(free or purchased) to better understand EPAct rules and requirements?

Thank you in advance to anyone who shares their insights..