Key Points
General Assessment: The PenPlace Project, Amazon’s HQ2 complex, demonstrates numerous outstanding elements of sustainable design and has the potential to become the first commercial zero carbon building in Arlington, helping to normalize advanced practices in sustainable design and construction in our region. The project should seek to achieve Zero Carbon Certification, identify additional opportunities to reduce embodied carbon in construction materials, and enhance biophilic elements through reduced hardscapes and more native plantings.
Certification: LEED Platinum, the highest level of LEED certification. The Zero Carbon Assessment indicates that Zero Carbon certification is feasible, and Amazon should be encouraged to commit fully to LEED Platinum certification.
Energy Efficiency: Energy models show an exemplary improvement of more than 30 percent over the current building standards baseline.
Electrification: Planned HVAC and hot water systems and in-house kitchen facilities are to be all electric but Amazon is planning to make natural gas available for retail foodservice facilities. Amazon should be encouraged to work with potential tenants to attract entrepreneurs committed to using electric appliances for retail food services.
Renewable Energy: Amazon has committed to the off-site purchase of solar energy along with roof-top solar panels to cover 100 percent of its electricity requirements.
Electric Vehicle Charging: Amazon will provide EV charging for 10 percent of its parking spaces and is considering adding the infrastructure to support EV charging for up to 50 percent. Amazon should be encouraged to maximize the number of EV-ready parking spaces.
Embodied Carbon: Amazon is exploring options to reduce the embodied carbon in the project’s construction materials and should be encouraged to maximize the reduction in embodied carbon, particularly for concrete.
Water Conservation: The project design incorporates multiple elements of water conservation, including WaterSense fixtures, onsite stormwater retention vaults, and appropriate selection of native plants
Biophilia: The project incorporates many biophilic elements in the design of outdoor spaces, brings connections to nature into indoor spaces, particularly in the helix, and uses bird-friendly glass, but additional measures could reduce hardscape in favor of native plantings.
Detailed Assessment
The size and high-profile nature of this project provide a unique opportunity to embody and overtly demonstrate the highest-aspiration measures for sustainable design and operation. The impact will extend beyond this project to help normalize advanced practices in sustainable design and construction so that developers, contractors, subcontractors, and material suppliers will have an enhanced familiarity and comfort level with materials and methods that may currently seem exotic. It will show the public, community leaders, and designers in Arlington and beyond not just what is possible, but propel widespread adoption of specific practices necessary to achieve our goals for 100 percent carbon neutrality by 2050.
Zero Carbon: The Zero Carbon Assessment demonstrates a clear path to carbon neutrality. The development team should fully commit to Zero Carbon certification through design and technology solutions to ensure that the buildings can achieve this goal. Specific recommendations include:
- Considering the magnitude of concrete construction, including below-grade stories, specify concrete to minimize its carbon footprint. Commit to reduced cement through concrete mix design and sourcing as noted in the Zero Carbon Assessment Decarbonization Opportunities.
- Commit to Options 2, Embodied Carbon/LCA Optimization and Material Ingredient Optimization, per LEED MR c2 and MR c4 credits, respectively.
- Continue scrutiny of embodied carbon in building materials throughout the development, using heavy timber and other wood construction where allowable by code to sequester carbon and enhance connections to the natural environment through its aesthetics. Using wood in the Retail Pavilions is a good example of this opportunity.
- Maximize total embodied carbon emissions through the project design itself and less reliance upon offsets.
Electrification and Renewable Energy: All-electric buildings are essential for achieving the County’s climate goals for carbon neutrality.
- The developer should define a new normal for food service tenants to use all-electric cooking equipment and achieve 100 percent electrification at the outset. Investment in natural gas infrastructure should be eliminated.
- Onsite solar should be maximized and promoted to building occupants and the community as a benefit of using this building. Co-locating green roofs and solar arrays can provide shade to plants and improve panel efficiency as well as furthering occupants’ sense of pride in working in a sustainable building.
Energy Efficiency: This project’s design, projecting an energy savings of 32.8% over baseline, is highly commendable. The development team should take the following steps to ensure and stretch beyond this goal:
- Given that glass constitutes a large proportion of the building envelope, incorporate the highest efficiency glazing systems available. Extend the use of triple pane glazing, planned for the Helix, to all other buildings on site.
- Refine the development of the facades to maximize winter solar gain and daylighting potential while using shading devices to minimize glare and provide summer shading. Reorient major facade elements on the office buildings to optimize solar gain. Follow the example of Virginia Tech’s Innovation Campus by sculpting forms to maximize performance and photovoltaic power generation, including incorporating PVs into the glass of the facades.
- SPRC review comments regarding the need for further differentiation among the office buildings, including the sculpting at the tops and mid-level setbacks, should be addressed through a climate-responsive lens: maximize PVs and vegetated building surfaces and orient facades for wind and solar responsiveness.
- Continue to refine detailed envelope studies and energy modeling during the design development to maximize climate-responsiveness and demonstrate performance.
- Build upon the planned enhanced commissioning through measurement and verification of building performance, including metrics that the public can monitor.
Water Efficiency: Reduced water usage, in addition to protecting this valuable resource, saves energy and reduces demand on our waste treatment facilities and proposed features are exemplary.
- Commitment to premium low flow plumbing fixtures should be combined with promotional messaging to building occupants, describing how their choices to minimize water use benefit the environment.
- Landscape plans should use all drought-resistant, native, and wildlife-friendly planting materials requiring no permanent irrigation.
- Proposed sharp reductions in use of potable water by tapping alternative water sources through stormwater detention vaults are planned to meet 100 percent of irrigation needs and 50 percent of indoor fixtures
Green Transportation: The project’s location sets the stage for modeling transportation practices that promote health and transform our behavior.
- As the site design details evolve, assure that safe, dedicated bike lanes are provided throughout the project with plenty of width to separate bikes and scooters from pedestrians. Remove at-grade parking where needed to accomplish this.
- Eliminate on-street parking other than pickup/drop-off parking for childcare and persons with mobility impairments. Plan for operational measures to enforce this. Ensure easy access for delivery and service vehicles below grade to prevent them from blocking bike and pedestrian routes.
- Minimize the impact of paving by maximizing rain gardens and other biophilic stormwater management design around pathways.
- Provide infrastructure to make all parking spaces EV-capable, to meet the future demand for a full transition to electric vehicles and avoid the need for much more expensive retrofitting.
Biophilic Design, Wellness, and Indoor Air Quality: The project’s aspirational design on the outside should be fully expressed on the inside, demonstrating healthy living and promoting wellness.
- Maximize the use of bioswales, plantings and green space around the building while minimizing paved areas.
- Maximize use of native plantings that support pollinators.
- Continue to review bird-friendly design aspects, especially considering the biophilic plantings that will attract birds. Scrutinize nighttime exterior lighting and building light spill to help protect migrating birds.
- Biophilic aspects of the design should extend indoors by including such elements as living walls that enhance indoor air quality in lobbies and other public spaces. Provide signage and other promotional materials that educate the public about the positive impact of indoor plantings on indoor air quality and health.
- The heights of these buildings provide many opportunities to promote movement while minimizing elevator use. Employ design features that enhance the attractiveness of stairs while assuring full accessibility for people with mobility impairments.
- Commit to low-emitting materials per LEED EQ c2.
Resilience: The project’s role as a community asset should extend to emergency preparedness.
- Scrutinize the design for climate resiliency, including verifying that design of all outdoor spaces maximizes flood mitigation to assure safe egress and shelter in extreme storm conditions.
- Consider how the extensive below-grade infrastructure could serve as a safe shelter for the community during extreme events through stormwater control and hardening of generator and battery backup infrastructure.
Documents
This content originally appeared The EcoAdvocate newsletter produced by the EcoAction Arlington Advocacy Committee. For more information about the Advocacy Committee, please visit ecoactionarlington.org/get-involved/ecoaction-arlingtondvocacy/