For a WindowMaterial:SimpleGlazing, the field visible transmittance is optional.
From the documentation:
This field is optional. If it is omitted, then the visible transmittance properties are taken from the solar properties. If it is included then the model includes it when developing properties for the glazing system. This is the rated (NFRC) value for visible transmittance at normal incidence.
I want this field to actually be calculated by EnergyPlus based on the solar data and not defaulted to 0.31.
Is there a way to NOT input a VT value in the Openstudio App or do I have to call resetVisibleTransmittance on the window using the api?
