The LEED Platinum CSHQA Boise Office, designed and built in just 10 months in a renovated 60-year-old railway warehouse, is one of the most energy efficient office buildings in the state. It is the only commercial building to employ radiant heating and cooling, and is regarded as one of Boise’s leading sustainability examples. As a project manager with Capitol City Development Corporation pointed out, “CSHQA moved the needle on urban design in Boise.”
The warehouse had good bones, and aside from a new, reinforced roof membrane, required minimal structural work. The engineering challenges were in civil, MEP, lighting, and telecommunications design.
In order for the entire project to meet financing pro forma, parking had to be negotiated with Boise City. Under basic code, the building would have been over half parking garage to provide required spaces. This was not feasible. A variance allowed street parking and further negotiations allowed angled parking. Eventually, CSHQA was allowed to design and install a permeable paver system to manage all building and site storm water.
Mechanical and Plumbing
Traditional HVAC systems were not going to meet our goals, high efficiency motors and pumps notwithstanding. After modeling six different heating and cooling systems, CSHQA engineers determined the most efficient system, with reasonable return on investment, was a heat pump system with radiant slab heating and cooling. This system is supplemented by high efficiency rooftop air handling equipment that also provides ventilation air. The building’s domestic hot water is also heated by the geothermal system.
In the first winter, during building commissioning, it was estimated the building could be heated for approximately $6 per day; during weekends without additional heat, the temperature never dropped below the low 60s!
Lighting and Controls
High efficiency T-8s are used in the main studio for even light distribution. Daylight harvesting utilizing photosensors and dimmers reduces energy use when natural lighting is available. Fourteen skylights were installed in studios and office spaces. All other lighting, including desk-top task lighting, is provided by LED technology. Overall lighting is controlled by a lighting control system.
The communications infrastructure supports 80 work stations and five conference spaces from a single, environmentally controlled telecommunications room with capacity for the next generation of media and equipment. The telecommunications room also houses access control, intrusion detection, video surveillance systems, the enterprise PBX, local and wide area network (LAN and WAN) equipment and UPS units. The five conference spaces are supported by locally installed equipment and software, providing audio and video conferencing with file sharing for multi-media presentations with our clients and remote offices.
Read Russ Pratt’s 2017 ASHRAE Technology Award submittal. This project earned an Honorable Mention for mechanical engineering design and innovation, and was one of only 17 projects recognized world-wide in the ASHRAE awards.