by MWilliams » Wed Sep 12, 2018 8:45 pm
I've overseen a lot of programming for many building types. Below are some of my shortcuts. The book Problem Seeking by Pena and Parshall is a great resource for programming standards. It has a whole section of efficiency/net to gross.
Net area is also called "net assignable". Space that can be assigned to someone for a particular use.
A lobby, beyond the "phantom corridor" required for egress, is net. Foyers and vestibules are gross.
I've found that a good starting point for estimating building efficiency is 80% x 80%= 64%.
Most utilitarian buildings are 60%-65% efficient. Warehouses much higher, courthouses much lower (less than 50%).
Here's how the 80% x 80% works:
Base building: about 80% available for floor layouts.
(the other 20% is structure, walls, mechanical spaces, building storage, shafts, elevators, egress stairs, public toilets, janitorial, etc)
Floor layouts: about 80% assignable.
(other 20% is interior corridors and partitions. (three lineal feet of partitions take up one SF)
hope this is helpful.