[F32Fleet]

Originally Posted by nyalpine90

from 20+ years of experience with architects and general contractors and other engineers from differ trades.

all trades must know the code what it takes to build an apartment, house or high rise building. The architect is responsible to bring the whole project together and for it to work properly. A well experienced architect will have knowledge of how the all trades, mechanical, electrical, plumbing systems work. Takes a good general contractor to build what plans indicate without mistakes. Its all written with details and explanations. Mechanical system which is HVAC is the most expensive item building a house, condo, apartment etc. Pricing set is always issued and has enough information from engineers,contractors,materials, everything is included to determine the cost of the designed home.

change orders are more common when your dealing with existing house, building and you dont know the conditions of pipes, wires, structural and supports. Once the demo/probing begins, walls are open. floors and ceiling are removed. At this point, things will change, now you may have to add cost for beams, new piping, new wiring etc.

i been designing plumbing systems for long time now. the impossible is possible.
it takes a good team to make things work smoothly.

Are you Yanks using PEX for residential builds?