Second question as I think I may have answered my first about demanding the receptacle loads,I believe I can.But the real question is this,I am in Iraq and building 29 new buildings,each with a panel fed from a MDP.Now,as I calculate loads per buildings and apply demands,when it comes to calculating the main service size,do I use the already calculated amperages from the individual buildings,Or can I take the entire job as a whole,all the lighting,all of the outlets and put one demand on all of it at once,I am trying to get this as low as possible but do want it to work....Hope this makes sense..Thanks from Anbar province Iraq