case study: sustainable mixed-use development in historic urban areas

ATLANTIC WHARF SUSTAINABLE CASE STUDY

Atlantic Wharf Sustainable Case Study

Boston Properties Owner

Vanderweil EngineersSustainability Consultant


Urban Design / Permitting Process

• Dense urban site at the entrance to Fort Point Channel neighborhood

• Proximity to down town and major transportation nodes

• Waterfront activation required by Chapter 91 permitting

Urban Design


Urban Design / Permitting Process

• Article 80 large project review

• Historic Approvals – Article 85, MHC, BLC

• Chp 91, MEPA &environmental approvals

Complex Permitting Process


Architectural Design

1.1 mm sqf overall- Office, Residential, Retail, major Interior Public Spaces, below-grade parking and exterior Public Space

Mixed-Use Program



• Full restoration of the historic 1899 Peabody and Stearns Russia Building and preservation of the GA and Tufts building facades to maintain the historic fabric at street level.

• The fully restored Russia Building will now house 86 luxury loft residential units.

Preservation of Historic Architecture - Existing



• Design integration of modern glass enclosed office tower with low-rise historic structure

• Tower form recalls the maritime history ofthe site

Integration of Historic and New Architecture



• Nelson Court was historically a streetway between buildings and now serves as the link between the new and historic architecture

• The 7-story glass-enclosed public space also serves as the office tower’s main entry

Integration of Historic and New Architecture – Nelson Court


Construction

• Up-Down Construction

• Hybrid Concrete Core and Steel Frame Tower

• Below-grade slurry wall garage

Complex High-Rise Construction


LEED – Core Shell Version 2.0

43 points - USGBC Pre-Certified GoldDesign Review Complete; Construction Documentation 95% complete


Sustainable Site Highlights

Sustainable Sites – 12 Points Achieved


• Constructing and renovating a building on a previously developed site in a dense community channels development to urban areas with existing infrastructure and preserves natural resources.

• Locating the project within ½ mile of a commuter rail and subway stations reduces pollution and land development impacts from automobile use

Development Density, Community Connectivity, & Public Transportation Access



• Roof storm water run-off is harvested in a 40,000 gal. basement level retention tank and re-used in HVAC process water, thereby reducing demand on municipal water systems

• Atlantic Wharf Reduces the amount of process water used by 15% as compared to a typical building.

•Typical Building Process Water Use: 6.98 gal/sf/year

•Atlantic Wharf Process Water Use: 6.01 gal/sf/year

Storm Water Management



• An 18,000sf vegetated green roof atop the Graphic Arts & Tufts Buildings utilizes native and adapted plantings to reduce the the heat island effect and minimize the impact on the micro climate and reduce storm water run-off

• Modular pre-planted grid system sits directly on roof membrane

Heat Island Effect: Roof



• Atlantic Wharf features a 650-car parking garage on 6 levels below-grade constructed with a slurry wall perimeter and post-tensioned concrete slabs.

• 100% of parking capacity underground, thereby significantly reducing the heat island and drainage effects caused by on grade impervious hardscape surfaces.

Heat Island Effect: Non- Roof



Water Efficiency Highlights

Water Efficiency – 3 Points Achieved


• 30% water-use reduction was achieved by utilizing low-flow and dual-flush plumbing fixtures in the core/shell design

• The combination of low-flow fixtures, stormwater re-use, and reducing irrigation water use by resulted in Atlantic Wharf reduced the domestic water use by 69% as compared to a typical downtown office tower.

• Typical tower domestic water use: 18 gal/sf/yeaf

• Atlantic Wharf domestic water use: 5.5 gal/sf/year.

30% Water Use Reduction

Water Efficiency Highlights


Energy and Atmosphere Efficiency – 7 Points Achieved

Energy & Atmosphere Highlights


• Overall energy performance demonstrates approximately 16% energy cost reduction compared to ASHRAE 90.1 2004

• Atlantic Wharf is designed to use 42% less energy overall than comparable New England office buildings

• New England Office Building Energy Use: 114.6 MBTU/sf/year (CBECS 2003)

• Atlantic Wharf Energy Use: 66.7 MBTU/sf/year

Optimize Energy Performance


electricity gas total

De-sign

1951695.746

169285.2 2120980.946

Baseline

2317490.098

199746.54

2517236.638

$250,000 $1,250,000 $2,250,000

Atlantic Wharf Annual Energy Cost Savings

8%1%

21%3%9%

5%

26%

24% 1%2%

Atlantic Wharf - 48 kBTU/SF

Space Cool-ing


Optimize Energy Performance


• Core/Shell Project controls approximately 2/3 of annual energy use with tenant design and operations influencing the other 1/3

• Boston properties is responsible for approximately 22% of “developed-controlled” saving, while holding tenants neutral

4 1

10

2 4 2

12 11

0 1 3 0

12

2 5

1

12 13

0

8

Atlantic Wharf Energy by End-Use

kBTU/SF/year

Design Baseline

Devel-oper;

$1,694,600

Tenant; $825,600


• Tenant sub-metering was implemented.

• Major core systems and public spaces metered

• Infrastructure installed for tenants to meter their own spaces

• Owner developed tenant sub-metering guidelines and will provide monthly reports prorated by tenants

Measurement & Verification



• Atlantic Wharf achieved a 42% increase in glazing thermal properties that contributed to reducing the building heating and cooling load.

• ASHRAE 90.1 2004 Glazing: .057 U-value

• Atlantic Wharf Glazing: .033 U-value

• Atlantic Wharf achieved at 32% increase in roof thermal properties that contribute to reducing the building heating and cooling load.

• ASHRAE 90.1 2004 Roof: .063 U-value

• Atlantic Wharf Roof: .043 U-value

Increased Envelope Thermal Properties



Materials & Resources Highlights

Materials & Resources Efficiency – 6 Points Achieved


• The design featured the restoration, re-use and integration of over 40% of the existing historic structures that were on-site. The Russia Bldg. was fully restored and the Graphic Arts and Tufts Building facades were preserved and integrated into the new architecture and structure.

• The re-use of the existing structures conserved valuable resources and significantly reduced the environmental impact of comparable new building construction as it relates to materials manufacturing and transportation.

Maintain 25% of Existing Walls, Floors, and Roofs



During construction over 95% of construction debris and soil was either recycled or re-used, thereby diverting this material from land fills.

Construction Waste Management



Over 35% of the project was constructed from post-consumer recycled content, primarily steel, aluminum and glass (check), thereby conserving natural resources and reducing impacts from processing and extraction of virgin materials.

Major contributing materials were structural steel, re-bar, aluminum, and glass.

Recycled Material Content


36%

2%0%

0%

62%

Atlantic Wharf Recycled Content

- Total 38%Steel & Metal


Indoor Environmental Quality Highlights

Indoor Environmental Efficiency – 10 Points Achieved


Base Building Design calls for 1,120 VAV controls points with capability to add an additional 1500 control points

The new VAV control system has the capacity to provide control points for all future multi-occupant work spaces and over 50% of the individual work stations

Controllability of Thermal Comfort Systems



The use of low-voc emitting paints, sealants, adhesives, and carpet in the core/shell project reduces the quantity of indoor air contaminants and improves the comfort of

the occupants.

Low-VOC Emitting Materials



The design incorporates outdoor views with direct line of sight for over 90% of the building occupants introducing daylight and views to interior areas of the building and improving productivity.

Occupant Outdoor Views




Innovation In Design – 5 Points Achieved


Innovation Credits

• Process Water Use Reduction – 15% reduction achieved by re-use of storm water run-off from basement collection tank

• 100% Structured Parking – 650-car underground parking garage significantly exceeding 50% requirement and therby reducing impervious surfaces and associated heat island effect.

Innovation Credits


Sustainable Challenges & Opportunities

Design Integration of New andExisting Structures

• Technical design and constructability challenges of integrating new design with existing structure:

• Temporary Steel Facade support required while existing GA/Tufts building demolition took place

• Structural slab edge slip connection to accommodate potential differential settlement of new and old structures

• Complex construction sequencing required to erect new foundations and super-structure alongside existing historic masonry facades


Sustainable Challenges & Opportunities

Inherent Sustainable Qualities in Urban High-Rise Development

• Many of today’s typical downtown, urban infill sites have inherent sustainable characteristics that assist in quickly achieving LEED certification levels due to the nature of their siting, design constraints, and current design and engineering best practices

• Typical earned credit areas include:• Development Density & Transportation access-siting

• Existing Building re-use – historic zoning

• High levels of Recycled content – high-rise construction

• Non-Roof Heat Island effect reduction – below grade parking

• Optimizing energy performance – design best practices

• Daylighting and views – design best practices

•Construction Waste Management – construction best practices


Ownership Perspective

• A 2008 CoStar study found that sustainable buildings outperform non-green assets in key areas such as occupancy, sale price, and rental rates and indicate broad demand by property investors and tenants for buildings that have achieved LEED certification.

• LEED Buildings achieve 7.38% higher rental rates over non-LEED buildings (2011 CoStar)

• LEED Buildings have 4.1% higher occupancy (2008 CoStar)

• LEED Buildings sell for an average of $171/sf more than non-LEED buildings (2008 CoStar)

• Tenant Marketplace is demanding sustainable buildings – Large publicly traded companies within LEED spaces felt that occupying ‘green space’ was important to their employees and their public image (2011 CoStar)

Increased Real Estate Value of Green Design


Ownership Perspective

• Total $1.58/sf/year in energy and water cost savings equates to $1.5 million per year in building savings, or $2.4 million for a 100,000 sf tenant over the life of a 15 year lease

• Typical Boston High-Rise Energy costs:

• $4.00/sf/year (Boston High-Rise Property Survey)

• Atlantic Wharf Energy cost: $2.59sf/year (as estimated from energy model)

• Typical Boston High-Rise Water cost: $0.25/sf

• Atlantic Wharf Water cost: $ 0.08/sf

Operating Cost Savings Associated with Sustainable Buildings


atlantic wharf sustainable case study

Question and Answer

case study: sustainable mixed-use development in historic urban areas

Real Estate

process article

permittingurban design

process dense urban

historic approvals article

mepa environmental approvals

large project review

major transportation

waterfront activation