Can anyone tell me if the addition of interior storm windows without a change in existing fixed windows would trigger having to meet either the prescriptive requirements or the ECB ch. 11 model requirements?
It seems to me, the storms only make it better.

I see that ASHRAE 5.1.3 makes an exception for storm windows as well as other envelope 'improvements'.
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does this prerequisite allow all of the exceptions in ASHARE 5.1.3?