Denver Maintenance Facility

• LEED Silver Certification, 37 points in LEED v2.2
• All-precast system using CarbonCast reinforcing technology
• Projected energy costs reduced by 24.5% over a typical code-compliant structure
• CarbonCast panels produced under license from AltusGroup Inc.

If the design and construction decisions precasters make for their own facilities can serve as inspiration for how to approach construction decisions, here is the story of a High’s maintenance building located in Denver, Pa. This precast concrete structure includes many elements of sustainable design, and High served an interesting dual role as both the client and engineer/manufacturer.

At an estimated cost of construction of $4.1 million, the building will be used by High’s maintenance department to service heavy trucks, pick up trucks and cars, and other plant equipment. The facility earned Silver Certification in the LEED® rating system for new construction through the U.S. Green Building Council (USGBC). Documentation for 37 LEED v2.2 points was submitted and approved.

To determine which green features would be integrated into the building’s design and construction, the project team began the process with a Green Design Charette, which typically lasts anywhere from a half day to a week, depending on the size and complexity of the project. The entire design team was present to discuss project goals, ideas, building systems, local availability of materials, site characteristics, grading, storm water, macro and micro climate including sun and wind considerations and possible code issues. This helped in the evaluation of different systems, cost impacts and the viability of meeting the credit criteria.

Performance

Elements that will enhance sustainability

In the LEED materials and resources category, it may seem like a given that a precaster would choose precast concrete for its building. But the durability and environmentally sound characteristics of the material make a strong case for its use by diverse clients. Today’s advanced carbon fiber-reinforced precast products are designed to increase durability and thermal efficiency, reduce or eliminate corrosion, and reduce weight. Additional characteristics of concrete result in a long list of green attributes:

• Precast panels can be re-used when buildings are expanded or repurposed in different applications, such as protecting shorelines from erosion
• Since the precast process is self-contained, formwork and finishing materials are reused
• Virtually all reinforcing steel is made from recycled steel
• Light-colored precast reduces heat island effect in urban areas
• Reflective or light-colored concrete requires less artificial light to illuminate the structure
• Thermal mass and reflective properties reduce the amount of electricity used for A/C during the heat of the day
• Thermal mass is beneficial in absorbing and retaining heat

The all-precast concrete building features thermally efficient sandwich wall panels fabricated by the company’s Springboro, Ohio plant. With insulating foam literally sandwiched inside them, the panels provide an R-value of 25 and are reinforced with innovative CarbonCast® carbon fiber shear trusses that make them fully structurally composite for load bearing. The roof is composed of CarbonCast double tees manufactured by the Denver plant. Also used for the driving surfaces in parking garages, the double tees are made with non-corrosive carbon fiber flange reinforcement and are 10 percent lighter in weight than traditional double tees.

Energy Efficiency

To further enhance the energy efficiency of the precast building, computer energy models and computer daylight modeling were used to optimize the HVAC systems and building envelope, as well as to determine the correct size, location, and glazing type for windows and skylights. The overall projected energy costs of the building have been reduced by 24.5 percent over a typical code-compliant structure through use of:

1. Thermally efficient wall panels reinforced with innovative carbon fiber to provide structurally composite performance for thinner, lighter wall sections
2. A highly insulated building envelope with a rating of R-24
3. Carbon fiber grid reinforced double tees that are lighter in weight and non-corrosive
4. Eight inches of insulation on precast concrete roof double T’s for a rating of R-40
5. Highly efficient doors and windows
6. A heating system consisting of a water-based radiant heat floor system (to provide uniform distribution of heat and comfort where technicians will work) and a boiler that will use waste oil from fleet vehicles
7. Highly efficient dimmable fluorescent lighting interconnected to photo sensors that determine foot-candle levels from natural light through skylights and dim or turn off fixtures as necessary

Other Details

Additional enhancements for sustainable performance

• Water Efficiency – reducing water consumption by 20 percent by utilizing special faucets on lavatories, showers, and low flow double flush water closets.
• Alternative Transportation (Parking Capacity) – providing parking capacity that does not exceed minimum local zoning requirements, and provide preferred parking for carpools for 5 percent of the total provided parking spaces.
• Heat Island Effect (roof) – providing a highly reflective roof surface which helps reduce heat island effect on the site.
• Enhanced Commissioning – beginning the commissioning process early in the design phase.
• Enhanced Refrigerant Management – utilizing cooling systems with select refrigerants which help to reduce ozone depletion and minimize direct contributions to global warming.
• Measurement Verification – implementing a plan that measures and verifies that the buildings energy performance is as designed.
• Construction Waste Management – recycling and redirecting construction and demolition debris instead of disposing of them in landfills and incinerators.
• Regional Materials – using a certain percentage of materials processed and manufactured regionally.
• Certified Wood – using a certain percentage of certified wood products, to support environmentally friendly forest management practices.
• Construction Indoor Air Quality Management Plan – developing a plan before occupancy of the building.
• Low-Emitting Materials – adhesives/sealants, paints/coatings, carpet systems, and composite wood/agrifiber products.
• Controllability of Lighting Systems – using system controls to promote comfort and well being of occupants as well as increase productivity.
• Daylight and Views – integrating skylights, windows, and vision panels in overhead doors, making a connection between the indoor environment and the exterior environment.