This is an analysis of the NW Federal Credit Union's "Green Architecture" design strategies. The specific focus is on the effectiveness of the overall building performance. In detail, the study focuses on the exterior shading devices and their performance through an analysis of interior and exterior temperature readings, user comfort evaluations, and computer modeling. The data was collected during two separate trips to the building. The results of the visits indicated that the exterior shading devices are not completely effective in shading the glazing throughout the year. The large south facing canopy, along with the other shading devices, provide sufficient shading during late spring, summer, and early fall. In the winter months however, the shading devices leave the first floor and part of the second floor exposed to direct sunlight (assuming the sun is shining in Seattle).
This is a good strategy for solar gain, but directly conflicts with the functions of the spaces. For security reasons, the first floor is unable to have window shades like the other floors which causes visual discomfort among the employees and customers. The light meter readings taken on a partly sunny day in April, show high light levels even without direct sun, while temperature HOBOs, recorded the changes in temperature.
As a solution we proposed to increase the overhang of the large south facing canopy by 20%. The results, shown by the virtual computer model, didn't alleviate all of the direct sunlight, but did make a significant difference in overall exposure. The other south facing shading devices were doubled in length, and tapering vertical elements were added to the east facing sun shades to alleviate glare from the direct sunlight.
Despite the effects of the low sun during the winter, the employee surveys showed the majority of the employees were quite pleased with the building. Shown in the pictures and in video, the third floor deck and lounge areas received the most compliments.