The multi-block scale of the Brewery Blocks development coupled with Brewery Block 4’s strategic design enabled the incorporation of a blend of technological and simple sustainable measures. From the unique treatment of the building’s stormwater runoff to the occupant’s ability to simply open a window, Block 4 demonstrates the benefits of designing for positive interaction between the building’s occupants, the natural environment, and the surrounding neighborhood. The design team was expanded to include an energy modeler, solar design expert, sustainability consultant, and commissioning agent. The Natural Step, PGE EarthAdvantage, and LEED were used as design guidelines and helped facilitate an integrated design process.
District Cooling Plant
Block 4 draws its chilled water from a high efficiency district cooling plant located on top of Block 1 that serves all of the Brewery Block buildings. The centralized system produces chilled water in bulk via evaporative cooling and is much more efficient than individual point of use chiller plants or air conditions, which would typically be used in a comparable facility. An outside air economizer and variable speed pumps on the cooling tower render the system demand-responsive and contribute to the related energy savings. The system also enables the use of a “low temperature” air distribution system that delivers colder than typical air to the building and subsequently reduces the overall size of fan systems and ductwork. All of the Brewery Blocks buildings are currently served by the plant’s two machines totaling 3,700 tons of cooling and a future build-out capacity up to 10,000 tons leaves the potential to serve a portion of downtown Portland as well. The district cooling plant and related strategies were designed using energy modeling and account for roughly half of the building’s total energy savings.
A garage ventilation system for the underground garage was designed to work at half of the code ventilation rate (from 1.5 CFM per sq. ft. to .75 CFM per sq. ft). This allowed for smaller fan systems and reduced energy consumption. The system was further enhanced by making it variable volume in response to actual carbon monoxide levels in the garage.
An innovative underground parking garage lighting system was installed using induction luminaries. These luminaries have a prolonged lifespan of 100,000 hours versus 2,000 hours of the more typical HID lighting and reduce the watt density from 0.30 watts per square foot to 0.13 watts per square foot. Additionally, these luminaries are capable of instant re-strike so they do not require additional circuiting or lamps to provide emergency egress illumination in the event of power failure. All of the walls, columns, and ceilings in the entire parking structure are painted white to further increase illumination efficiencies.
The Portland Streetcar and two different bus lines travel right through or adjacent to the building, allowing quick and easy access to downtown and the MAX light-rail line that serves all of Portland. Secure bike storage and full-service bike commuter locker rooms with showers and over 100 lockers are provided in the parking garage. These features are all designed to increase pedestrian activity, encourage bike commuting, and reduce auto use.
In addition to pedestrian amenities, ample bike parking and transit access, there is also a parking stall reserved for a Flexcar carshare vehicle located along the east side of Block 4 on NW 11th Avenue. As more residents and office tenants move into the Blocks, a space for one additional Flexcar car may be made available.
Live, work, play
The Brewery Blocks are designed to attract and serve a diverse mix of people and to successfully integrate public transit into daily life. The five blocks have been planned as an 18-hour live/work/play mixed-use environment. Ground floor retail with a mix of shopping, entertainment and dining establishments and people-friendly streetscapes keep the streets active and safe. The streetscape and building frontage is designed to be pedestrian-friendly as well as to complement transit facilities. These features make the Brewery Blocks a safe and affable conduit linking downtown Portland and the Pearl District.
Envelope - Sun
Block 4’s envelope is marked by a significant south-side setback that promotes solar access to the building’s tower throughout the year. This design strategy enabled the installation of a power-producing photovoltaic system, integration of natural daylight into the building’s lighting plan, and vegetation of the setback.
Original plans for a photovoltaic system included building integrated photovoltaics and a rooftop array. Upon arrival of the façade-destined PV panels however, it was determined that they did not suit the architectural and aesthetic character of the building and these panels were instead mounted on the rooftop. The rooftop array includes 77 polycrystalline modules (BP Solar BP3160) powering a grid-connected inverter (Trace PV15208) and is expected to generate an annual output of 13,400 kWh at 174 kWh per module.
The southern façade arrays consists of amorphous silicon thin film modules contained in arrays that are framed extensions of the spandrel panels. There is one 4-square array located at each spandrel with a total of 192 individual modules (2 of which are inactive) that are expected to generate an annual output of 8,200 kWh, or 43.1 kWh per active module. The extensions create the ability to increase the angle of the arrays greater than 90 degrees and hence generate more power. Total annual system output is expected to be 21,600 kWh.
The daylighting strategy in Block 4 integrates tall windows, interior light shelves and two types of glazing to reduce the building’s dependence on electrical lighting. The glazing below the light shelves is improved to reduce glare and has ratings of VLT 35%, SC=.31 on the south, east, and west facades and 70% VLT, SC=.43 on the north facades while the glazing above the light shelves is more lucid to promote penetration and reflectance of natural light deep into the building. This strategy created the capability to substantially decrease the demand for artificial lighting.
Water - Inside and out
A 17,800 ft2 extensive ecoroof planted with drought-tolerant, native vegetation consisting primarily of sedum species is located on the fourth floor setback. The ecoroof attenuates stormwater from the lower roof and upper level balconies on the south side and is then directed to the nearby-buried Tanner Creek via underground pipe. Stormwater enters the buried creek downstream of a sanitary diversion pipe after it goes through a manhole filtration system know as a “downstream defender”. The “defender” will earn the project the LEED stormwater treatment credit and has removal efficiencies of 90% for sediments and 30% for phosphates. The remaining water will be used via vegetative uptake and evaporation. The total amount of water handled by the ecoroof annually is approximately 320,400 gallons. The upper roof, and 80% of the total roof, is topped with an EnergyStar-compliant roofing system.
Low-flow fixtures are used throughout the common areas of the building, resulting in a 25% reduction in water use over code. Landscape features are designed for zero irrigation once they are established, further reducing the amount of potable water usage at each building.
Block 4 is designed to facilitate the creation of a healthy and productive workspace. The building’s core and shell systems create the capacity for tenants to have more control over their immediate environment while realizing significant energy savings.
Manually operable microclimate controls provide each individual control of their personal thermal comfort. Tenants can manage the amount of airflow entering their workspace by simply adjusting the diffusers embedded in the raised access floor. Operable windows further increase tenant’s environmental control, access to fresh air, and provide a connection to the outdoors.
Only low-toxicity, low-VOC paints, sealants, carpets and adhesives were used in Block 4. Senior Project Manager Dennis Wilde indicates that, “Some materials, specifically paints and other low VOC finishes do not have the durability of their more polluting counterparts. This is changing as more products come on line.” Smoke control in the buildings is based on the use of operable windows, using a “smoke reservoir” configuration, which eliminates the need for smoke exhaust fans and allows for downsizing generators.
Flexible floor plans enhance the ability to adapt to the tenant’s changing needs and materials that are easily recycled during tenant changes and building modifications were specified where possible.
Keys to Success – Design:
- For multi-building developments, install a high-efficiency centralized cooling plant
- Specify an air economizer and variable speed pumps on any cooling system
- Integrate a “low temperature” air distribution scheme that reduces the overall size of fan systems and ductwork
- Design a garage ventilation system that reduces the required ventilation rate and subsequent energy demand
- Install a carbon monoxide monitor to regulate garage ventilation
- Locate near public transportation and provide alternative transportation accomodations
- Create a live/work/play mixed use environment that promotes 18-hour pedestrian activity
- Design the building envelope to render the sun and rain an asset to the building’s operation and occupants
- Install an ecoroof to attenuate and filter the building’s stormwater runoff
- Specify low-flow fixtures throughout the building to reduce overall building water consumption
- Design easy-to-use manually operable climate controls
- Specify low-toxicity, low-VOC paints, sealants, carpets and adhesives
- Design flexible floor plans and specify recyclable materials to accommodate tenant changes