Hunter Industries: Maximizing Energy Efficiency and Design

[ By Mark Langan ]

A 2,000-square-foot space below the second floor patio deck gives employees options for outdoor contact while providing shade to the building.

Over the past 25 years, Hunter Industries, one of the leading manufacturers of landscape irrigation equipment for commercial, residential and golf course industries, has utilized technology in a successful approach toward revolutionizing its industry. It applied that same approach toward developing a new state-of-the-art facility in San Marcos, Calif., to house 44,270 square feet of sales, marketing and customer service space, together with its new 95,000-square-foot distribution center.

Historically, Hunter Industries has been progressive with its approach to energy efficiency, as demonstrated by its existing co-generation plant and gray-water recycling program. By incorporating innovative technologies into the new design, Hunter Industries demonstrates its commitment to the environment and the firm’s direction toward sustainable design.

Incorporating Site Uses

The newest building of the existing San Marcos campus created a number of programmatic challenges. The facility houses diverse uses and combines a highly visible lobby and sales department with a distribution center. The first challenge was the siting of the building and the need for separation between the “public” side, where facility tours and sales events occur, and the “private” distribution side. In addition, the building was sited between two existing multi-family residential developments located within a master-planned community, creating both visual and noise challenges.

The solution was to utilize two site entries: the “public” access from the west and the “private” access from the east. By extending a dead-end public street to the site, truck access avoided any circulation conflict. Studies were then done to ensure visual screening from the multi-family housing of both the trucking bays and roof-mounted equipment. The solution was a 45-foot-high warehouse wall, which housed the high-density building sprinkler system pump. Every project has unique challenges and similarly unique solutions. One of the challenges with this project was its existing soil conditions. Located on a rocky hillside, the project site transitioned from bedrock to imported fill material. The key here was to get the building to sit on a uniform material so that any movement or settlement through the building would be minimal.

The initial plan proposed by the geotechnical engineer was to over-excavate the rock areas and bring fill to create a uniform fill pad for the building to rest upon. After further analysis during the structural foundation design, the contractor was asked to do a cost comparison between the engineer’s option and excavating the bedrock. The chosen solution was to create a slurry mixture that could be poured on top of the bedrock, then to pour the concrete building foundation on top of the slurry. This allowed the foundation to be smaller since essentially it was being laid on top of bedrock rather than soil.

The Building Design

Hunter Industries provides 100 percent of the electricity to support the entire buildings’ lighting needs, a savings of $35,600 annually based on today’s energy rates.

Maintaining Hunter Industries’ corporate image was essential to creating a new signature LEED building. Hunter Industries had established many building standards with respect to materials, colors and amenities that reflected the company’s culture.

To create the signature building for the sales component of the company, Smith Consulting Architects devised a design theme that introduced a metal elliptical form at the two-story “public” entry element. The 45-foot-high walls of the distribution center reflected some of the same theme materials, with stone and a complimentary color scheme creating a backdrop for the two-story office and entry lobby. The areas within the elliptical component of the building are the lobby, cafeteria and outdoor deck for entertaining; the body of the offices retain Hunter Industries’ efficient building standards. In addition, the design used sustainable interior finish materials with low or no off-gassing from volatile organic compounds (VOCs), present in paint, carpet, wallpaper, insulation and their adhesives.

“Green” Landscaping

With Hunter Industries being a leader in irrigation technology and products, consideration was given to the presentation of landscape material and the products being developed by Hunter Industries. Working in concert with the landscape architect and Hunter Industries, Smith Consulting Architects integrated such design elements as a “green screen wall,” which added plant material on the vertical face of the 45-foot-high walls of the distribution center. A serpentine design softened the mass of the walls while reflecting the softer elliptical curves of the public entry.

A large second floor deck was incorporated into the design of the building for outdoor entertaining. For this deck, Smith Consulting Architects designed a series of built-in stone clad planters, each with a metal canopy trellis. Vines will eventually grow up the trellises and create natural shading. In addition, a large opening was included in the deck that allows bamboo to grow from below. Palm trees were utilized around the lobby and deck that accentuate the elliptical form of the deck and lobby. The palm tree canopies surrounding the deck are illuminated at night, creating a soft boundary while reinforcing evidence of Hunter Industries irrigation systems sustaining the landscaping.

The Photovoltaic Approach

One of the key elements of meeting and exceeding both LEED and utility company standards with the Hunter Industries facility was its use of revenue-generating, energy-producing systems. Two independent photovoltaic (PV) systems generate a total of 160-220 kilowatts (kW) of power, and are located on the roof of the building. The first is an 80 kW PV system that provides 100 percent of the daytime lighting needs for the entire building and has a construction payback period of under five years. At that point, the building will continue to be subsidized with free energy off the grid, thus giving Hunter Industries a competitive edge and, as an added benefit, saving 40 tons of polluting hydrocarbons from entering the atmosphere each year.

The second key element is the 102 kW PV system resulting from a unique collaboration between the local utility company, San Diego Gas & Electric (SDG&E), and Hunter Industries. This second PV system is made possible by Hunter Industries’ commitment to saving 25 percent more energy than the stringent California Title 24 Energy standards and, in doing so, qualifying for the Sustainable Communities Program (SCP). The program is set to promote sustainable development and showcase energy efficient design and building operations in San Diego, Calif.

Under the Sustainable Communities Program, the 102 kW system is owned and operated by SDG&E and located on roof area leased back to SDG&E by Hunter Industries. This collaboration generates some direct revenue from SDG&E to Hunter Industries while simultaneously allowing SDG&E to provide enough power back to the outside utility grid to supply electricity equivalent to the use of 40 to 70 single family homes. In addition, the solar power generated saves an additional 40 to 140 tons of hydrocarbons from entering the atmosphere each year.

Taking advantage of the financial incentives offered by utility companies like SDG&E means doing your homework and starting the design process early. SDG&E’s new construction representative helped direct both the Hunter Industries and Smith Consulting Architects teams to the appropriate incentive program and eligibility requirements for the specific design assistance services and cash incentives that would be beneficial to the project.

Utilizing Natural Daylight

White packaging with the 32-foot high racking system, white painted walls and white-faced insulation help reflect all available daylight. The 162 harvesting units have multiple lens construction and motion and light sensors.

The 95,000-square-foot distribution portion of the building has 100 percent of its daylighting needs met with 162 daylight-harvesting units provided by Daylight Technologies® in San Diego, Calif. These innovative fixtures provide diffused, natural lighting in a single rooftop unit that also includes the physical support for the 80 kW PV system, the backup/night lighting, motion and light sensors. This fully self-contained unit decreases the need for independent structural support and roof penetrations typically required by each component if installed separately, saving both money and time while reducing the potential for costly roof leaks.

Additional sustainable approaches include an Energy Star “cool roof” system designed by the Mansville Corporation to reduce heat gain, and high-efficiency rooftop mechanical equipment. In any large building, the roof diaphragm is a critical component of the building structural systems and, as such, penetrations are typically minimized. However, in this case, San Diego Fire Code required smoke venting in case of fire, and therefore the natural daylighting system needed to have a great number of roof openings. A technical report was prepared and presented to the Fire Department and resulted in an agreement to minimize the number of smoke vents while not compromising public safety. Concurrently there were studies performed for the roof daylighting systems to determine the exact number and spacing required to allow the appropriate foot candle levels needed for reading product information at the ground level of the building. After locating these openings, the task became one of designing a roof diaphragm to effectively distribute the lateral structural loads while creating an efficient and reliable construction system for the large area of the roof. Balancing Distribution and Energy Efficiency

Efficiency of the distribution area was a delicate balance between Hunter Industries, its many design team consultants and the local building code enforcement officials.

For this facility, the team needed to balance the efficiency in product flow, energy efficiency and construction cost efficiency. In this case, the team started with the maximum building height allowed, which dictated the maximum storage racking height. Colbrese Material Handling, the material handling/racking consultant, developed the most efficient storage configuration for the building’s phased growth using this height limit. The building structure was then designed around that storage system.

A fire sprinkler designer was hired early in the design process to coordinate an ESFR (Early Suppression Fast Response) fire sprinkler system to accommodate the racking height and plastics stored. With this design in place, the team could design specific building structural roof members to support the very large sprinkler piping rather than over-design the entire structural roof system.

All teams worked together to create an effective and efficient storage system, natural lighting system, code compliance safety system, and building construction system. Smith Consulting Architects is proud to be part of the design team for the new Hunter Industries sales and distribution facility, which represents a new standard of sustainable design for private industry.