Using a design software which allows use to see what is happening in real time. Which is called B.I.M.  What is B.I.M.? B.I.M. is the acronym for Building Information Modeling It is a drawing system that allows you to see in virtual 3D what is being designed.  There by allowing the designer to pre-empt system conflicts in the design stage before construction starts.

The system also gives your client the opportunity to make changes in the design stage after "seeing" the finished product before construction begins, rather than when it is nearing completion.  Which can cause costly changes and delays.

Another advantage for you as the contractor is that we have the ability to give a complete material and cost estimate without doing a manual takeoff.  

The end result is a set of building permit drawings that everyone can use and understand without the headaches of conflicts.