Heating, Cooling, Daylight, and the likes

I used this opportunity both to explore my ECS systems in-depth and to test graphics for my final presentation.

In winter, at the peak of the school’s occupancy, heat loss through the envelope does not far exceed internal heat loads (occupants, lights, and equipment).  Though Portland’s perpetually overcast winters make solar heating a challenge, the small heating load can be met using a ground source heat pump, delivered through a radiant slab. Thus, the high-mass, high-insulation interiors create a very stable interior environment. If occupants feel that they need an on-demand heat source, rambunctious children is also a good resource.

In summer, these same systems work to create cool indoor climates. Night-flush of mass, as well as the ground source heat pump, create cool interiors that remain comfortable for the low occupancy levels expected through the summer season (mostly small summer school activity and occasional community programs).

Though all parts of the building are provided ample opportunities for daylight from two sides or more, I took a deeper look at the daylight performance of the Savanna Commons. Overhangs and clerestory openings provide direct access to sunlight (or what little is available) in the wintertime, while blocking most direct rays in the hotter months. Through testing of a physical daylight model, I was able to achieve a very desirable daylight factor of 4.0 for much of the space. Because all daylight to the space comes from high clerestories, the center of the space receives the highest lighting levels, while the perimeter is somewhat dimmer. The use of a baffle near the lower half of the windows redirects some of the light to the room’s perimeter without compromising light that penetrates deeper in to the space.