The LEED Green Building Rating System is a feature-oriented rating system where credits are earned for satisfying green building criteria. The LEED program has been adopted nationwide by federal agencies, state and local governments, and interested private companies as the guideline for sustainable buildings.

The building architect was Group Mackenzie of Portland, and the general contractor was Opus Northwest, a national firm headquartered in Minneapolis. The mechanical contractor was American Heating of Portland, and the building mechanical and electrical design was done by System Design Consultants of Portland. Michael Kinne from that firm directed the mechanical design for the facility. According to Kinne, "Our firm focuses on high-efficiency building designs. It was exciting to be involved in this design, particularly with the LEED aspect."

Kinne pointed out that a separate contractor, Hatten/Johnson Associates of Eugene, Ore., did energy modeling at the design stage. Using DOE-2 and other software tools, the contractor evaluated the anticipated performance of the building. Kinne emphasized that this was especially important for the facility because of the high ventilation rates needed for many of the areas, and the complexity of the heat recovery systems.

Also integral to the project was the commissioning agent, PECI of Portland. The firm was involved from the design stage onward, and its role was to verify that all of the systems were operating as intended.

Trane Oregon, the Portland commercial sales office for Trane, was actively involved in the project, not only in providing equipment, but also in working with building designers and contractors to evaluate equipment options and in programming individual equipment and the entire building control system.

Several aspects of the Honda facility used green approaches, including rubber flooring made from recycled auto tires to a fire lane outside the building that was surfaced with a grid of recycled plastic. On the HVAC side of the project, the warehouse section of the building was equipped with supplementary gas-fired unit heaters for freeze protection. The office area of the facility utilizes a raised-floor system for distribution of conditioned air, with the entire floor cavity serving as a supply plenum for a system of distributed variable air volume (VAV) terminal boxes with low velocity floor diffuser outlets. According to Kinne, the system provides great flexibility.

"They can make lots of changes in the cubicle design and still have adequate ventilation and comfort management," he said.

The underfloor system is supplied conditioned air by a variable volume rooftop air handler, and has separate intakes for ventilation air. The raised floor consists of lightweight concrete panels covered with carpet tiles made with recycled materials. The floor cavity is also used as a convenient location for control, telephone, computer, and electrical cabling.

The air handler supplying this area is a Trane T-Series Climate Changer unit designed to provide precise ventilation control and complete mixing of conditioned air. A rooftop air handler was selected in order to conserve interior space in the building. The T-Series product is a modular design, which allows it to be tailored to specific applications.

The high-bay shop area, which is used for automotive training, receives conditioned air from another constant-volume T-Series Climate Changerâ„¢ air handler. Ventilation air is delivered to overhead diffusers and returns to the air handler from overhead collection points. Building exhaust air goes through a heat and cooling recovery system to conserve energy usage.

A unique feature of the training area is a system for extracting waste heat from automotive exhaust from each of the training stations. Each of the 25 training stations is equipped with a flexible collection tube, which conducts the exhaust from operating engines to a rooftop heat recovery section. The recovered heat goes to the air handler for ventilation air tempering. The training shop area also features an in-floor heating system, which is supplied by the heating boiler. The system supplies heat at floor level, where it is needed most.

The three rooftop air handlers receive chilled water from a single Trane 80 ton Series Râ„¢ Model RTWA screw chiller in a grade level mechanical room. This chiller type was chosen to deal with operating efficiency over a wide range of loads. Condenser water from the chiller is piped to a Baltimore Air Coil low-profile cooling tower. The air handlers are also supplied hot water from the building's heating boiler.

The entire facility is controlled by a Trane Tracer Summitâ„¢ system with NIST-traceable sensors and 1,400 data collection points. The system maintains comfort levels throughout the building and also helps control other features including rainwater collection and storage operations and ventilation management. Also important is the Summit system's ability to collect and log data for the continuing LEED building maintenance verification plan.

Publication date: 01/26/2004