Since I'm pursuing the prescriptive method of this prerequisite, I am filling out the entire AEDG.  For the Daylighting and Lighting section, it asks for interior surface average reflectance in terms of 80% ceilings, 70% wall surfaces, and 50% open office partitions.  In order to determine this, can i just sum up the ceilings and wall surfaces in the architecture drawings and make a percentage of the surface area which have a white surface (since white is usually reflective) out of the total surface area?