Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question

Revision history [back]

Hi Steph,

What is your reason for running a 3-phase (or 5-phase) method in this instance? Are you planning to replace the glazing with different daylighting systems? If not, then you are much better off running a simple Daylight Coefficient (DC or 2-phase) method for annual simulation. This does away with the need for a BSDF, since you simply put the glass in your model and use a single run of rfluxmtx to calculate the interior connection to the sky through the building. This method is described in section 2.2 of Sarith Subramaniam's tutorial https://www.radiance-online.org/learning/tutorials/matrix-based-methods

If you do use a BSDF for the window, you might use the "aBSDF" specification, which looks for a view component to result in a more accurate calculation. However, applying a BSDF should always be of necessity, as other methods are more accurate for simple glazings.

Best, -Greg