For calculating Daylight Factor in criterion 13 (GRIHA Version 3), we are using the following method. Kindly comment whether it’s correct or not.
- Run the simulation for indoor Illuminance (lux), for various living areas
- Calculate the Daylight Factor using formula Daylight Factor = (Ei/Eo) x 100 %, as mentioned in GRIHA manual (where Eo is as per climatic zone as mentioned in the manual)
This method is acceptable. Some of the software used for day lighting simulation calculate the Daylight Factor directly too.