Duct sizing, velocity, static pressure, friction loss, supply and return air, exhaust systems, diffuser selection, and air balancing — moving Module 4's load numbers from the coil to every diffuser in the building.
Module 4 turned a building's loads into a selected piece of equipment and a nominal airflow. This module is where that airflow actually gets somewhere — sized ductwork, checked against velocity and static-pressure limits, split correctly between supply, return, and exhaust, and delivered through diffusers chosen for throw and noise together, not cfm alone.
The same 3,000 sq ft retail building and 10-ton rooftop unit from Module 4 carries through every section here, and the module closes on air balancing — verifying in the field that the system installed actually delivers the airflow this module calculated on paper.