I have entered high-efficiency mechanical equipment for a tradeoff, but the REScheck compliance index for the 2006 IECC does not change. Why?
The most likely reason is that your home has a better compliance index under the envelope U-factor times the Area (UA) compliance path than under the performance path. If you use high-efficiency equipment and your house fails under the UA path, then REScheck evaluates your house’s 2006 IECC compliance using a simplified performance path. This is a different REScheck mechanism for determining the mechanical equipment tradeoff than was used for older codes. However, as for the older versions of the code, the mechanical tab in the software is still optional. If you are already meeting the energy code requirements, you do not need to enter any information about your HVAC system. Because the new simplified performance path takes into account many home features that are not considered in the envelope UA path (e.g., glazing SHGC, orientation, and window-to-floor-area ratio), switching to the performance path doesn”t always improve compliance, even if high-efficiency equipment is specified. I
Related Questions
- I have entered high-efficiency mechanical equipment for a tradeoff, but the REScheck compliance index for the 2006 IECC does not change. Why?
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