In the heating and cooling loads, I had separated my building into separate zones comprised of classrooms, gallery spaces, and other sections determined by how much heat they will gain through the sun. This is important as some of my spaces are largely subterranean and will have less fluctuation than, for example, my largest exhibition space.
According to the climate consultant, my location in California's Climate Zone 3 (Stanford) requires mostly heating. Because my building will be located in the hills and parts of it won't receive much sunlight, I have opted to only install heating and use passive strategies to cool the building rather than have active cooling systems. This means I will install ventilation and heating. I opted for radiant heating because it is most efficient and less invasive.
Based on this set of strategies, I need to implement lots of ventilation and sun shading, along with high thermal mass. Passive thermal gain will also aid my design.
What is left to be implemented is proper insulation. Additional ventilation can be implanted by making some of my curtain wall panels into openable casement windows in the classroom and upstairs hallways.
I ventilated most of my building to ensure that it meets all requirements. I was able to prevent from adding ducts to the hallways and atrium because I anticipate adequate natural ventilation in those areas.
Upon reaching this point in my model, I realized I have enough space for an air handler on the roof, but not enough space for an air handler for the bottom level. I have opted to split the ventilation/cooling systems into two sections - one for the eastern side of the top floor, which will receive the most solar heat and remain the warmest, and one for the rest of the building. The top floor will be served by an air handler on the roof, whereas the rest will be served by another air handler I can add on the exterior of the building on the south side, near the egress pathway. This can be added later or modified accordingly without major changes to the project. This way, the areas most in need of cooling can be served by a single air handler, and the rest of the building which might need regular/reduced cooling or ventilation can be served by a separate one. This also leaves more roof space to serve our solar needs.