QUESTION:

When using the thermal calculation to determine the solar gain into a zone, are the different optical properties of glazing taken into account by ECOTECT ?

ANSWER:

Yes. In the Material Properties dialog box, all window elements have the following properties:

• Shading Coefficient
• Transparency
• Refractive Index
• Alternating Solar Gain.

All these are considered in the Thermal Analysis calculations when determining direct and indirect solar gains in each zone. Incidence angles and refractive effects are calculated for each hour using the current Sun position for that date/time.

You should note that, unlike the thermal analysis functions, the Solar Exposure and Cumulative Insolation functions only calculate the radiation actually falling on each surface, not passing through or being absorbed. In the next version (v5.50) both absorption and transmission values are shown along with incidence in the tables and graphs.