The New Forest Hills Borough Building- A Net Zero Energy Solution
By Patricia M. DeMarco, Forest Hills Borough Council 2016-2020
February 28, 2017
Forest Hills Borough, a community of about 6,500 people located seven miles east of Pittsburgh approaches its centenary in 2019. The town was once a rural farmed area then became a company town for Westinghouse with settlement intensifying after WWII. Long associated with innovation and Westinghouse engineering feats, the town has been shaped by the legacy of parkland and public property donated when the company moved on in 1985. The Forest Hills Borough Building on Ardmore Boulevard stood as the center for Borough functions since 1922, but now faces the limitations of an inefficient and costly energy system, and other structural problems.
In August of 2014, a general annual review of Borough properties revealed significant cost escalations in several Borough buildings: the Magistrate Building and the Borough building on Ardmore Boulevard, and the Library and Senior Center on Avenue F. The Magistrates Offices moved to a larger office space with better parking and access, vacating the building, and Allegheny County consolidated the Senior Services Center to Turtle Creek, closing the Forest Hills location and two other small centers. Removal of Senior Services from this location left a 20-hour per week C. C Mellor Library function in a building that was expensive to operate, and had limitations with accessibility and functional services. The Borough Building on Ardmore Boulevard had significant limitations in storage, space for citizen services, and accessibility to the second floor Council chambers, even with an elevator. The Police functions have significant limitations in space and security arrangements, and parking and pedestrian access to the building are limited. Most concerning was the increasing cost of operations, and the unsuccessful adjustments to the heating and cooling system in the interior space. Even with repairs and adjustments over recent years, inefficiencies and space pressures were unlikely to be resolved in the existing space.
A plan emerged to build a New Forest Hills Borough building on property the Borough owns on Greensburg Pike, adjacent to the Westinghouse Lodge and Park. The new building will consolidate the Borough administrative and Council functions, Police offices, and the Library/Community space into one efficient building to serve the needs of the community 50 years into the future. By moving the New Forest Hills Building to an existing Borough property location, the sale of the existing properties would contribute to the financing, and the existing property on Ardmore Boulevard will return to a taxable business use. The goal of Council was to achieve a functional municipal services building for fifty years into the future without increasing the tax mill rate. A target cost of $4.5 million was set as a goal.
Public presentations on the concept of a New Forest Hills Borough Building began in February 2015 with concept discussions presented by Town Center Associates. Soon after, the Borough retained Pfaffmann & Associates to work with Council to define a plan for the new building. In addition to monthly public meetings at Council sessions, two Community Planning Meetings were held in September 2015, focusing on the Site Plan for the building, and in April 2016, focusing on the Functionality and Design.
The New Forest Hills Borough building site is on a gravel parking area formerly the location of a Westinghouse building on Greensburg Pike. At the site planning meeting, there was considerable interest expressed by several residents in restoring the Westinghouse Atom Smasher structure as a site feature. The Atom Smasher is currently on the ground on a property under consideration for development by a private entity that has no interest in preserving the historic artifact. A designated location for this atom smasher is included in the site plans, however, the cost of moving it from its current location and refurbishing it for safe installation on the new Forest Hills Borough building site has been estimated upwards of $200,000. Private sources of funds are being sought for this project. Many citizens are interested in seeing the new building reflect the history of innovation that has been part of Forest Hills over the years.
The site was evaluated for a passive solar building design, and was deemed suitable, if the building could be oriented on the property to allow a south-facing roof. If a geothermal earth heating and cooling system would be included, soils testing and evaluation of the site for coal shafts under the area would be necessary. This site sits at the top of the Turtle Creek watershed, therefore, the area was also evaluated to address storm water management with bio-swales and green management techniques to control storm water runoff. The location already has direct access to Greensburg Pike with ease of traffic movement and is served by a public transit bus line. The site is large enough to accommodate parking, and has sidewalks for safe pedestrian access from multiple directions. Its proximity to the Westinghouse Lodge and park create a campus of Forest Hills Borough public services.
Functionality and Design
At the community planning workshop, groups of citizens drew concept plans for the functions to be served in the new building. Imaginative proposals included a coffee shop /internet café, a history walk capturing images of Forest Hills over the last century, and interpretive exhibits explaining the features of the building. The Forest Hills Borough administrative staff, Police Department and Council had an opportunity to add thoughts and have participated in all stages of the building design planning. A rough outline of the building emerged on the wall, and discussion turned to how to meet the needs for the next century. The group quickly agreed that sustainability and cost efficiency take high priority in the design. Citizens familiar with the Phipps Conservatory and Botanical Gardens Living Building features and the Chatham University planning for the Eden Hall sustainable design added credibility to the concept. People were concerned that such an ambitious sustainable goal would be too expensive for the community.
Focus on the Building Envelope with an emphasis on sustainability took the approach to “Reduce Consumption before Renewables.” Design parameters were set around energy, water, materials and indoor air quality. Considerations included the need for adequate storage and natural daylight in work spaces; areas for serving the public both in Borough Administrative functions and in public service in the Police Department. The spaces for library and community gathering were discussed in terms of how they would relate to the Council chamber under different configurations of uses. The preference for natural materials and locally sourced materials gave guidance in the design for the building envelope and interior treatment.
Forest Hills Town Hall Sustainable Features
The building will be a 12,746 square foot one-floor structure aligned with a south facing roof and a clear story of translucent recycled plastic to filter incoming light into the interior space.
Architectural Drawing for New Forest Hills Borough Town Hall – Under Construction January 2017. Credit: Pfaffmann & Associates
A passive solar designed building has first focus on the building envelope. The building will have an energy use intensity of 36.78 kBtu/ft2 with an estimated annual cost of operation of $10,670. This design will have an operating cost of $0.97/ft2, compared to the current building cost of $2.21/ft2, or the cost of operating a building designed to the conventional 2009 building code standard of $1.42/ft2. Forty 100-foot deep geothermal wells will provide heating and cooling and will require 118,555 kWh annually to operate. The 125 kW photovoltaic array on the roof will provide 151,947 kWh annually which will cover the geothermal HVAC plus the other electrical loads in the building for a Net Zero Energy operation. The building will be connected to the utility grid with a net metering tariff for electric service. A gas line will be connected to an emergency generator to support police operations.
The design for storm water management will reduce the peak discharge rate into Turtle Creek watershed by more than 64% over the 100-year storm level. The volume of water from 2-year and 5-year storms will be entirely infiltrated as will nearly all of the 10-year storm volumes. A system of sand and limestone infiltration beds will reduce runoff acidity and temperature, and rain gardens and plantings will provide additional water filtration benefits. The site will be planted with trees and drought tolerant and native plants in bio-swales surrounding the building and as features in the parking area. Enhanced pedestrian walkways and some of the parking lot will be of permeable surfaces to augment storm water infiltration.
The first principle is to design the building to conserve energy as much as possible. Therefore, the building will be super-insulated with the roof at R50 (conventional is R 38), R-40 walls (Conventional is R19). Natural daylight and views to the outdoor plantings enhance the ambiance and provide attractive work spaces. The clearstory along the roofline is of translucent plastic formed material that allows light, but prevents glare to the interior. The windows are of insulated glass set in wooden frames, and have sashed sections to open for ventilation in season. The southern roof overhang allows shading in the summer and sunlight to enter in the winter. Sustainable non-toxic materials are used throughout for walls and structural materials. All the wood is from sustainably grown sources. Materials were selected for recycled content, locally sourced and environmentally beneficial performance. Lighting is designed to use natural daylight, with LED lighting and daylight sensing controls. Water management includes water-conserving plumbing fixtures with automatic controls to reduce water use. The lobby and reception area will be equipped with a “dashboard” and interpretive signs to explain how the building functions and allow visitors to understand the special energy and water conserving features.
The design plans were approved in November of 2016, and a General Contractor, Volpatt Construction, was hired. Groundbreaking ceremonies on December 3, 2016 marked the beginning of a new era for Forest Hills Borough.
Images of the design appear in this booklet prepared by Pfaffmann & Associates.
The new Forest Hills Borough Building will perform at the level of a LEED Gold building, although certification will not be sought due to the cost. The Council has been in unanimous accord with this project across two administrations. The community is well engaged with the project and as construction proceeds toward an December 2017 completion target, excitement is building for this innovative and fiscally responsible project. This New Forest Hills Borough building will reflect the history of innovation that has shaped this town and show the way forward for resilience in a changing world.
This article was published as a Guest Blog for Pittsburgh Green Building Alliance at https://www.go-gba.org/the-new-forest-hills-borough-building-a-net-zero-energy-solution/