Kitsap County Administration Building
- Building Name: Kitsap County Administration Building
- Building Location:
- City: Port Orchard
- State: Washington
- Country: USA
- Project Size (ft², m²): 75,379 square feet
- Building Type(s): Office
- Project Type: Public
- Delivery Method: Design / Bid / Build
- Total Building Costs: $240 per square foot
- Owner: Kitsap County Department of Administrative Services
- Building Architect/Project Team: Miller/Hull; Craig Curtis, FAIA; Sian Roberts, AIA; Rob Misel, AIA
- Project Contact Person: Rob Misel
Completed in June 2006, the Kitsap County Administration Building located in Port Orchard, Washington, is a 75,000 sf building. Approximately 200 people now work in the Administration Building which consolidated five County Department offices previously spread across the County. Serving as a civic hub for the County campus, the building is located between the County Courthouse and Public Works Building.
The property presented a design challenge with a 55-foot change in grade across the building site. The design response was to terrace the building into the hillside, which allowed for multiple, narrow floor plates. The construction is primarily cast-in-place concrete with a pre-cast plank floor system. The building skin is a combination of limestone cladding and glass. A two story steel canopy on the south side of the building provides shade and a dramatic civic entrance.
The building creates connections with the surrounding environment on three levels. The new Division Street Plaza acts as a pedestrian nexus connecting the Administration Building with the adjacent Public Works and Courthouse Buildings. The relationship between this hilltop campus and downtown Port Orchard is strengthened through visual and physical links including the development of the Cline Avenue Stairs. The regional context of Sinclair Inlet and the Olympic Mountains influenced the site design through the careful placement of overlooks, resting places and seating areas that capture the stunning views afforded by the site's location.
The Kitsap County Administration Building is the physical embodiment of 'a window into your local government'. We designed it to be an approachable, tangible and substantial commitment to environmentally sustainable civic architecture in Kitsap County.
Kitsap County was very interested in demonstrating their sustainable commitment to the community. To enhance occupant comfort and energy efficiency, the Administration Building features terraces, operable windows and natural venting instead of air conditioning. The interior environment of Kitsap County Administration Building was designed with sustainability in mind; from occupant contentment and retention rate to preserving our energy resources. Open office lighting was designed with linear fluorescent, T5HO, indirect pendants with 0-10 volt dimming ballasts. Daylight zones are created near glazing walls and skylights that contribute to interior lighting. Each fixture length in the daylight zone utilizes integral daylight sensors to control the light levels in that zone depending on the amount of natural daylight being sensed in the area. This sensor integration eliminated the need for additional ceiling drops for separate sensors in the space, allowing for a cleaner installation, and it provides tighter control of each fixture length in the zone. Occupancy Sensors were integrated into the control system and are very cost effective in the open office areas, as they eliminate wasted energy by turning lights off when room occupants forget. In order to fully capitalize on the sun's power, photo sensors, in conjunction with a time clock, allow outdoor lighting to operate only when daylight is not available.
This project's commitment to sustainability continues outdoors. To take full advantage of the mild Puget Sound climate, fan assisted natural ventilation was incorporated into the design of the Kitsap County Administration Building. The building includes four large open office areas that have a long wall with windows able to be opened by occupants. These areas receive their cooling air directly from the outside, drawn in through the windows. When the building automation system determines conditions are appropriate, a light will illuminate in the office and an email will be sent asking occupants to open the office windows. A building fan gently pulls the proper amount of air through the windows to maintain comfortable conditions inside the space. Energy and cost savings result from decreased use of the building HVAC system. Less energy is used to cool the building in the summer due to limited use of hot, south-facing windows, and increased use of north-facing windows which provide indirect outside light. Where windows were desired in spaces that faced the sun, extensive overhangs were installed to reduce the room solar heat loads in summer.
Less energy is used to cool the building in the summer due to limited use of hot, south-facing windows, and increased use of north-facing windows which provide indirect outside light. Where windows were desired in spaces that faced the sun, extensive overhangs were installed to reduce the room solar heat loads in summer.
The open office spaces are based on a European concept and are somewhat narrower than in most American offices. This concept is built around everyone being within 30-feet of a window. In the Kitsap County Administration Building, deeper areas are accented by skylights, and where windows occur, an ability to open them to fresh air is provided.
The Building also takes advantage of the site's steep topography by burying itself into the hill — and stepping down the hillside — an approximate 55-foot change in grade. This allows for a gracious terracing of office spaces, and a reduction in scale to the building which keeps it from looming over adjacent houses. Within the open offices, the incorporation of skylights at the rear of the spaces allows natural light into spaces deep within the building, and contributes toward the overall building cooling. The cool soil adjacent to the office spaces cools the space much like you'd find down in a cool basement on a hot, summer day.
Recycled content materials were used in the project including carpet, gypsum wall board, rubber flooring, concrete, and acoustic ceiling tile. Job site recycling of construction debris and waste has also been specified. The use of low and no VOC materials help protect indoor air quality.
Three artist's work was incorporated into the building design on the 1% for Art program. This is Kitsap County's first project to do so. David Franklin (wood carvings), Frank Samuelson (paintings) and William Robinson (stone sculpture) each contributed significantly during design.
In an effort to reduce the projects potable water consumption this site was designed with innovative systems for the capture and re-use of rainwater. The majority of the roofs on site are covered in a green roof system. The green roofs help to reduce storm water runoff rates, building mechanical costs and solar reflection. The green roofs consist of a 6" soil profile and a drip irrigation system to provide water to the plants during periods of drought. The green roof plants are comprised of drought tolerant species and only require water in the driest of times. This supplemental irrigation system for the green roofs is connected to a series of cisterns which stores and re-uses roof and site run off for site irrigation.
Now that the site plantings have been established, the cistern/detention system is able to provide 100% of the irrigation water for the site vegetation during the warm-weather months. During the winter months rainwater from the cisterns overflows into a day-lighted rain channel that parallels the Cline Avenue Stair. This culminates in a lower plaza that features a seasonal rain garden and an open, stone-lined basin. A sustainable site design is expressed through the use of native, drought tolerant and low maintenance plant species. These principles are made evident in the demonstration garden on the north side of the building, as well as in other landscape areas surrounding the site.
The new building's design has many sustainable attributes. The design process began with an Eco-Charrette as a brainstorming session to set environmental goals for the building which were closely tracked and evaluated throughout the project's development. The steep site is a natural for earth sheltering and rainwater collection.
Managing and conserving site water is an issue that the Design Team worked on collaboratively. Water harvesting was a primary goal of the Eco-Charette; Miller|Hull worked closely with the Landscape Architect and Civil Engineer to reduce the projects potable water consumption on the site. The Design Team developed an innovative system for the capture and re-use of rainwater. By studying the weather and rainfall patterns in the area and comparing them with the detention requirements and likely site irrigation needs, a system of rainwater collection and detention was developed with the goal of providing 100% of the site irrigation needs.
A series of rainwater cisterns were placed around the perimeter of the building to collect rooftop drainage and can hold over 110,000 gallons of rainwater. The majority of the roofs on site were covered in a green roof system. The green roofs help to reduce storm water runoff rates, building mechanical costs and solar reflection. The green roofs consist of a 6" soil profile and a high-efficiency drip irrigation system that features water efficient irrigation fixtures and a rain sensor shut-off (which assisted in establishing the plants initially). The green roof plantings consist of drought-tolerant species and only require water in the driest of times.
During design, we seized upon the opportunity to tell a story about how the building collects rainwater. Instead of hard-piping the overflow rainwater directly to the City's storm system, we allowed the excess capacities to overflow via several waterspouts into a dry creek bed, or seasonal stream along Cline Avenue. From there, the overflow rainwater flowed downstream to an open, stone lined basin at the foot of the slope. The collection basin was planted with seasonal grasses and reeds and provides the connection to the City's storm system. Beyond the collection basin a demonstration garden was located along the north elevation of the building, which also consists of native, drought tolerant and low maintenance plant species.
Keeping sustainability as the main focus, the Design Team worked together to design a building that minimizes the use of electricity and natural gas. Windows, walls and roofs have been well-insulated, often in excess of energy code requirements, to reduce energy consumption during the heating season.
Products and Systems
Green building practices were used for the project, including recycling of jobsite materials and debris. Interior materials — carpet and flooring, gypsum wallboard and ceiling tile — have been reused for the new building.
A number of factors were developed to help meet the goal for overall energy efficiency. Temperature changes were reduced by four elements—deep overhangs at glazed openings, green roofs, the mechanical air system, and the use of natural lighting. The overhangs shelter the earth and reduce heat gain at entrances and window areas. These areas are usually susceptible to temperature changes due to outdoor weather conditions. The thermal mass provided by the green roofing system offers a higher insulation value than standard roofing systems. The mechanical air system is comprised of an efficient under-floor air distribution, incorporating fresh air to assist in cooling and heating the building. Even when the windows are closed, the air system provides a constant flow of fresh air–improving indoor air quality by reducing the presence of odors and contaminants inside. Furthermore, the use of natural day lighting, even in earth-sheltered portions of the building, was incorporated into the design through the use of skylights and open office spaces, ultimately reducing the need for artificial lighting. Light sensors at window areas read outside light levels and automatically adjust the interior lights accordingly.
Where ever possible, recycled content building materials were used in the project. These products included Low VOC carpeting and paint, post-consumer material for tile flooring, acoustical ceiling panels, and roofing membranes, energy efficient appliances, formaldehyde-free insulation, LEED standard veneer finish, low E glazing, water reduction bathroom fixtures, permeable decomposed granite in landscaping, fly ash concrete, and electric arc furnace processed steel products.
To ensure the project would be incorporated into the neighborhood with the lowest impact, public spaces and views to the water were preserved and enhanced by design. The work of three local artists is integrated into the project, which further ties the new civic building with the Citizens of Kitsap County whom it serves.
Indoor Environment Approach
An under floor air distribution (UFAD) concept was selected. UFAD is an alternative approach to conventional ceiling-based systems for providing ventilation air and space temperature control for building occupants. The approach relies on introducing slightly pressurized air in the space beneath a raised floor, instead of moderately pressurized air in an extensive ductwork system located in the ceiling space. Results indicated that the selected under floor air distribution system will have an estimated life cycle cost savings of $175,000 to $330,000 versus common, traditional HVAC systems such as variable volume system with fan-powered displacement ventilation and water source heat pumps. Overall, this mechanical system will save the County about 10% more annually over an overhead ducted system and over 40% annually over a heat pump system!
A. Lessons Learned
The Kitsap County Administration Building was designed to be a good neighbor - the scale of the building matches the properties of those around it. The building creates connections with the surrounding environment on three levels. The new Division Street Plaza acts as a pedestrian nexus connecting the Administration Building with the adjacent Public Works and Courthouse Buildings and invites you to view 'your government at work' through expansive windows and a community of connected County Departments.
The relationship between this hilltop campus and downtown Port Orchard is strengthened through visual and physical links including the development of the Cline Avenue Stairs. The regional context of Sinclair Inlet and the Olympic Mountains influenced the site design through the careful placement of overlooks, resting places and seating areas that capture the stunning views afforded by the site’s location.
Employees have the benefit of improved thermal comfort due to the building's integral earth sheltered structure, green roof system and concrete building mass. The Building's green roofs allow for greater water infiltration and a reduction of overflow into the city's sewer system along with the added benefit of a greenscape which is seen from all floors of the building. The building’s green-roof system also helps to reduce evapotranspiration.
Most office spaces in the building are served by the innovative HVAC system - underfloor air distribution for heating. Instead of a traditional extensive overhead ductwork HVAC system, a raised floor was slightly pressurized with ventilation air that flows to building spaces through occupant-adjustable floor diffusers. Because the air flows gently upward, instead of being forced downward at high velocity from the ceiling, many advantages result. These include:
- Improved thermal comfort and indoor air quality - occupants determine how much fresh air is appropriate in their local environment, while stale air is pushed up above occupant head height.
- Reduced energy consumption - due to smaller fan motors, more efficient movement of room air, and fewer days per year when mechanical cooling is required
- Increased flexibility and reduced costs during future office layout reconfigurations, and ease of maintenance access to equipment beneath the raised floor.
Green building practices were used for the project, including recycling of jobsite materials and debris. Interior materials — carpet and flooring, gypsum wallboard and ceiling tile — were used for the new building.
The measures taken to ensure a healthy and productive working environment for Kitsap County employees has resulted in better indoor air quality, an opportunity to view and enjoy natural light and ventilation, and work in a building that not only is flexible and functional, but uses the earth's resources wisely. It has given the people that work in the building a reason to be proud of where they work and contributes to the quality of service that is subsequently offered to the citizens of the County.
- 2009 SBIC Beyond Green Award
- 2008 Merit Award, AIA Seattle Chapter 2008
- 2008 Honor Award, AIA NW & Pacific Region
- 2007 Merit Award, AIA Washington Civic Design Awards
- The Kitsap County Administration Building is featured in Miller|Hull’s new book Public Works.