Petal Certified


For the Nature Lab at Phipps, Phipps Conservatory and Botanical Gardens in Pittsburgh, PA sought to construct one of the nation’s first sustainable, modular classrooms as part of its larger efforts to highlight the important connections between people, plants, beauty, health and planet, particularly as they relate to human and environmental wellness. Approximately one in three schools in the U.S. currently uses modular units, which provide a quick solution for expansion but are commonly cited for the potential health risks they pose due to poor ventilation, compromised indoor air quality, high levels of toxins, mold, excess moisture, inadequate lighting and lack of natural daylight. Using the guidelines of the Living Building Challenge, the Nature Lab at Phipps reinvents the modular concept, daring to imagine a learning space that is net-positive energy, net-zero water, is built with non-toxic materials, includes ample daylighting and creates a space that fosters inspiration, education and beauty.

The classroom, which is the second of its kind in the world, originated from a design by the Seattle, WA-based SEED Collaborative. To fabricate the classroom using local materials, make customizations suited to the Western Pennsylvania climate, and tie the classroom into an existing sanitary water treatment system on site, Phipps contracted with EcoCraft Homes – a local company – a partnership which would ultimately result in EcoCraft becoming the SEED Collaborative’s official East Coast manufacturing partner. The building is a high-quality construction, unlike conventional modular structures, and while Phipps’ classroom is permanently installed, similar facilities could be moved if needed.

Since opening in March 2015, the Nature Lab at Phipps has been utilized for several principal purposes. As the new home of Learning for a Greener Future – an annual summer high-school internship program which offers a variety of work experiences, classes, community service projects, and field trips to a select group of students from under-resourced communities in the region – the classroom is proving its ability to reinforce hands-on environmental learning through its very design. It is also utilized as a programming space for Phipps’ popular summer camps for ages 2 – 9, which use the lens of nature to touch on topics including ecology, conservation, healthy living and art. In August 2016, a beehive was installed inside the classroom to demonstrate the importance of pollinators and highlight the environmental issues that threaten them.

vital stats

Certification StatusPetal Certified
Version of LBC2.1
LocationPittsburgh, PA, USA
Project Area5,120 SF
Gross Building Area955 SF
Start of OccupancyApril 2015
Owner OccupiedYes
Occupancy TypeScience Education
Number by Occupants10

project team

OwnerPhipps Conservatory and Botanical Gardens
ArchitectSEED Collaborative
ContractorEcoCraft Homes
PlumbingIams Consulting
GeotechnicalCivil and Environmental Consultants
CivilCivil and Environmental Consultants
LandscapeStudio Phipps
StructuralQuantum Consulting Engineers
Specialty Consultants and RolesEnergy Independent Solutions – Solar
Key SubcontractorsStructural Modulars Inc.
OtherBIOS EPS – Commissioning Agent

site petal

Photo Courtesy of Banko Media, Inc.


The Nature Lab and adjacent Center for Sustainable Landscapes sites were previously dilapidated gray and brownfields once used by the City of Pittsburgh Public Works department as a fueling station, and had suffered decades of environmental devastation. Remediated, polluted soils were replaced by engineered soils. The landscape design approach was to achieve interrelated goals: improve building performance and local water quality and provide visitors and students with a beautiful space to engage with nature and to enhance ecosystem services. The plant palette consists exclusively of species native within a 200-mile radius of Pittsburgh that are tolerant of both saturated and dry soil. The curated habitat provides food and habitat for local wildlife, including hummingbirds and bees. A colorful ladybug house encourages naturalized integrated pest management and is used in educational programming. Locally-produced organic compost mulch mix serves as the only amendment, and a stone path through rain garden encourages exploration and connects people to the very elements that the site’s regenerative landscape is designed to preserve and protect.


The Nature Lab is sited on the Phipps Conservatory and Botanical Gardens campus; this project scale jumps to the Phipps campus scale to comply with this Imperative. Elsewhere on the Phipps Conservatory campus, edible food is grown and harvested for the café, catering, and other programming needs.

Scale jumping to achieve this Imperative allowed Phipps to direct its plant selection strategy toward illustrating creative uses of water capture and reuse. Located within the Nature Lab at Phipps is a 21 square-foot living wall that focuses on tropical plantings and is intended to be fed by water from a demonstration sink (see more on this under the Water Petal). The exterior entry ramp to the Nature Lab parallels a 438 square-foot functioning interpretive rain garden for children’s science educational programming. The rain garden accepts the rainwater that overflows from the interior cistern. The non-edible plants incorporated therein were chosen because they have seasonal beauty and will thrive in this location, reflecting a “right plant, right place philosophy” espoused in all of Phipps’ sustainable gardening education and outreach efforts.


For its offset selection, Phipps chose to support the purchase and protection of 1 acre of land at the Helen B. Katz Natural Area in Vernon Township, Crawford County, PA, which is managed by the Western Pennsylvania Conservancy, an accredited land trust. The Katz Natural Area is a 380-acre property that includes wetlands, floodplain and a creek, providing habitat for a wide variety of wildlife including beavers, wood ducks and a variety of songbirds. On this site, which came into the management of the Conservancy thanks to a $5 million bequest by Mrs. Helen Blockstein Katz, about 35 acres of former agricultural fields are reverting to forest. The site is also a site popular with hikers and other explorers of nature, and its role in connecting the public to the beauty and importance of wild, natural, biodiverse spaces makes it a perfect complement to the goals of the Nature Lab and the larger mission of Phipps.

Name of Habitat Exchange ProjectKatz Natural Area – Reserve
Location of Habitat Exchange ProjectHayfield Township, Crawford County, PA
Name of Participating Land TrustWestern Pennsylvania Conservancy
Land Trust Website


The Nature Lab at Phipps was installed on a portion of the campus that was historically a road and hardscaped area. The new classroom was built as part of a multi-facility “Living Campus” on Phipps’ lower site, and no additional parking spots were added to compensate for the new auxiliary program structure. The Nature Lab is the second of three buildings comprising a “Living Campus” on Phipps’ lower site, which will contribute toward a human powered environment. The project team reconnected a historic biking and running trailhead back to Schenley Park as part of the site development of this project. The project also connects to a newly established bike network that links to adjacent neighborhoods of Oakland, Squirrel Hill, Greenfield, and Shadyside. Phipps has worked with the City of Pittsburgh to advocate for this new bike network that parallels its property in Schenley Park and connects the campus to local neighborhoods.

A secure and covered bike storage area will be located within the Exhibit Staging Center facility that will be renovated in 2017 – 2018. The new facility adjacent to the Nature Lab will include a new changing and shower facilities for staff and visitors. The Nature Lab is one story and does not require any elevators. Also, the lower campus that the classroom is being integrated into utilizes two electric charging stations.



Net-zero water requires that the project’s internal water demand must be satisfied by captured precipitation or closed loop water systems that account for downstream ecosystem impacts and that are appropriately purified without the use of chemicals. Achieving net-zero water was a particularly complex challenge because of code and state and local laws, which do not distinguish between “gray” and “black” water and do not allow the reuse of water for potable purposes. In the Nature Lab’s water system, a rain-fed cistern feeds a hand-pump demonstration sink. Water from this sink was intended to feed a living wall of plants. Since the rainwater passed through the demonstration sink, however, it is considered “black water,” or water potentially containing biological waste, and is not permissible to use in any capacity. Therefore, the plant wall cannot be fed by the demonstration sink, and the water from the demonstration sink is sent to the constructed wetland system of an adjacent campus building that cleans wastewater for reuse as flush water. Captured rainwater not used for the demonstration sink is also reused as flush water, and water from the toilets is cleaned by the on-site constructed wetland system for reuse.

Phipps and a local law firm are currently petitioning the state to modify the code through the Pennsylvania Department of Environmental Protection to make a distinction between “gray” and “black” water. This would allow the systems in the classroom to be more efficient, but also has massive potential water conservation impact if scaled up to other organizations across the state.


Roof runoff at the Nature Lab at Phipps is captured in an indoor cistern. Any overflow from the cistern is channeled to the Nature Lab’s rain garden. The cistern, pump and UV filter system provides irrigation for the green wall and for non-potable classroom water needs. The system feeds a hand-pump and demonstration sink used in educational programming. It also supplies all of the Nature Lab’s toilet flushing water. All sanitary water is treated on-site via constructed wetlands, sand and UV filters, and is used for toilet flushing at the adjacent Center for Sustainable Landscapes. Excess water from this system is further treated with a solar-powered distillation unit and used to irrigate plants in an adjacent campus building. Site rainwater that falls outside the footprint of the classroom is infiltrated via porous soils and an adjacent rain garden.

The classroom is set on a pier foundation system that allows the site to remain pervious underneath it. The rainwater captured from the roof is funneled through the interior and exterior cisterns and then overflows back into the site as it would have prior to the classroom placement. Water used for the handwashing sink in the bathroom is drawn from the city system, per code requirements; grey water from the bathroom sink is also minimal; the amount of water collected would be sufficient to provide water for the handwashing sink if codes were to eventually allow it.


Early in the design phase, the team presented the Nature Lab and its reuse water systems and composting toilet to the Allegheny County Health Department – Plumbing Division, and the PA State DEP. At that meeting, the team was told they were not legally allowed to drink rainwater, separate sinks/floor drains for reuse, and install a composting toilet. The team ended up going through multiple design iterations working with the local agencies and eventually built a grey water separation system. However, legally they still would not allow the project to reuse that water, even for irrigation. The team ended up installing a toilet that uses rainwater and sends sanitary to the existing on-lot sanitary constructed wetland. Years after occupancy began, the team finally obtained a permit from the local ACHD to install a composting toilet in 2017 and had conversations with ACHD to raise their plumbing codes from 2009 to 2015. Also, a pro-bono lawyer that was inspired by the Nature Lab and the team’s advocacy for water reuse is helping the team submit a rules changing petition to the DEP to push them to define grey water at the state level.



To achieve net-zero energy in the Nature Lab, Phipps used an outside-in, passive-first strategy: a robust building envelope, an energy recovery ventilator, solar tubes and high-efficiency fixtures and appliances keep energy use low. Structural Insulated Panels (SIPs) and R-49 ceiling + R-40 wall insulation (30% above code) help to insulate the Classroom and reduce heating demands. An Energy Recovery Ventilator (ERV) contributes to optimum ventilation and indoor air quality as well as heightened energy efficiency. Triple glazed windows within the space and Solatube skylights maximize natural daylight and dramatically reduce the lighting load. A 6 kW rooftop solar array generates more than enough electricity for annual net-zero performance; in its first year of operation, the Nature Lab generated 6,415 kWh of energy and used only 3,118 kWh, making the building net-positive. Building management data points allow Phipps to obtain real time energy production and consumption statistics and make adjustments as needed. With its energy-generation and water-capture equipment exposed for guests to see and interact with, the classroom’s inner workings are designed to put transparency and education first.

EUI: 11 kbtu/sf/yr (during performance period)


The Nature Lab’s role as a publicly accessible and replicable model calls attention to the importance of providing healthy learning environments for children and demonstrates how classrooms of the future can be built to maximize student wellness and potential.


Natural light is of utmost important in a classroom. Research conducted by the California Energy Commission shows 20 percent and 26 percent improved learning rates for math and reading, respectively, in classrooms with daylight compared to those with little or no daylight. Every occupiable space in the Nature Lab has operable windows that provide access to fresh air and daylight, as well as views of nature. Twelve operable windows and large French doors, coupled with Solatube skylights, ensure that the classroom is lit naturally the majority of the time. When necessary, dimmable supplemental lighting automatically turns on at the appropriate brightness level.


According to studies performed by the EPA, “…indoor air pollution is among the top five environmental risks to public health. Good indoor air quality (IAQ) is an important component of a healthy indoor environment, and can help schools reach their primary goal of educating children.” Poor indoor air quality often present in conventional portable classrooms can hinder cognitive performance and be detrimental to student and teacher health. The Nature Lab at Phipps is designed to maximize indoor air quality, resulting in a healthy space for growing minds.

The Nature Lab’s enclosed vestibule features an integrated walk-off mat to help prevent  contaminants from entering the space in the first place. Ventilation in the bathroom is provided by a connection to the ERV, which is designed to meet CFM requirements for schools and is supplemented with a ceiling fan and operable windows.

Results from air quality tests at pre-occupancy and at least nine months after occupancy measuring Respirable Suspended Particulates (RSP), Total Volatile Organic Compounds (TVOC) and Carbon Dioxide (CO2). CO2 levels do not exceed those stated in ASHRAE-62. The project makes use of wall-mounted sensors with displays to provide occupants with information on space temperature, humidity and CO2 levels.


The concept of “biophilia” – as coined by Erich Fromm and popularized by biologist E.O. Wilson, who defined it as “the innately emotional affiliation of human beings to other living organisms” – has long been a part of the green building toolkit, and a set of dependable strategies has emerged to help inspire connection to nature. The Nature Lab at Phipps incorporates many biophilic strategies: ample windows afford natural light, ventilation and views of the outdoors; furniture from reclaimed and FSC-certified wood connects staff and visitors to the natural environment; and the strategic placement of plants, including a large plant wall, beautifies the space while cleansing the air of toxic agents. As part of a larger campus, including the Living Certified Center for Sustainable Landscapes with which it shares a project boundary, the Nature Lab goes beyond conventional strategies to reap the rewards of the green building experience and awaken the spirit of the building in its young visitors. The classroom’s front door opens onto an FSC wood deck and rain garden curated with native plants and designed to provide food and habitat for wildlife. On rainy days, students can hear the rainwater capture in process, since the tank is present inside the classroom, and can even open the tank to see the water level. A ladybug house introduces children to integrated pest management through one of its most child-accessible ambassadors. A nature-inspired outdoor sculpture – part of Phipps’ BETA (Biophilia Enhanced Through Art) Project to bring a new dimension of sensory engagement to green buildings – overlooks the Nature Lab and helps to unify the outdoor landscape. The bold steps taken by Phipps to further the concept of biophilic design have resulted in a campus where buildings, nature and art flow seamlessly from one to the next. An observational beehive in the classroom allows kids to safely get nose to antenna with bees, permitting rare interactions that mesmerize and inspire.


Photo Courtesy of Phipps Conservatory


Access to safe, healthy places in which to live and learn should be universal, but are often not. The Nature Lab at Phipps is an example of how we can build in a way that respects the connections between human and environmental well-being and is equitable and accessible.

The classroom is rooted in its endeavor to connect students, teachers and visitors to the components of construction and function, demonstrating the interlacing of built and natural environments. It is created to be a hands-on teaching tool, to inspire and educate its occupants on sustainable design and holistic systems thinking. All of the systems within the Nature Lab are exposed. This allows visitors to walk in and ask questions about what they are seeing, and begin to understand and make connections with something as simple as how energy gets to a plug from the electrical panel, to something as complicated as how water is collected, used, treated and reused.

The classroom is built to be portable or permanent, allowing it to be set lightly on its site. At Phipps, the Nature Lab’s siting intentionally allows visitors the experience of traveling through the constructed wetland and landscape that helps the classroom function. Visitors then enter the building to make further connections as they see the systems and components of the classroom utilize natural elements like rain and sun.


The Nature Lab at Phipps shows what a healthy learning space can be. It was placed to be an education space available to area K-12 schools, a place for Phipps to house its own enrichment programs for students and a space to educate visitors and the community. This is represented by the “Learning for a Greener Future” summer internship, which is housed in the Nature Lab. The paid internship, which is offered exclusively to low-income/underserved audiences, provides a variety of work experiences, classes, community service projects and field trips in the diverse fields of environmental and plant sciences. Throughout the program, interns work with Phipps’ skilled science education and horticulture staff, college interns and volunteers, as well as experts from Pittsburgh’s environmental community. Graduates from the internship can then choose to become trained, paid docents that engage with visitors about the Nature Lab during weekly open hours.

By opening the classroom for tours and various events, Phipps also aims to inspire others in need of educational space to think beyond the standard portable classroom or permanent classroom space and incorporate Nature Lab and Living Building design concepts and educational elements into their projects.


Building projects that “aren’t as bad” are not going to be good enough. Restorative projects that return ecosystem services will be necessary to achieve safe and healthy spaces for all. The Nature Lab at Phipps and its surrounding site is ecological rebirth. On what was once a brownfield and paved-over public works yard, guests are now greeted with a restorative project that generates its own energy, captures rainwater and features native plants that provide food and shelter to wildlife.

Panther Hollow Lake sits downstream and downhill from the Nature Lab site. Runoff from the site prior to the Center for Sustainable Landscapes and Nature Lab had eroded the hillside and deposited pollutants into this once clean body of water that is part of the City of Pittsburgh Parks. By capturing all water on site, the classroom mitigates this and plans to restore the lake are already underway.


Photo Courtesy of Bank Media, Inc.


Above all else, it is the promise of beauty that draws visitors to a public garden, and people are compelled to admire, explore, understand and protect the things they find beautiful. For more than 120 years, Phipps Conservatory and Botanical Gardens has excelled in showcasing beauty. Today, this history of excellence serves as a platform to demonstrate that people, plants, health, planet and beauty are inextricably interconnected, and that sustainable action – from the construction of the world’s greenest building to the planting of a raised vegetable garden bed in a backyard – is the key to ensuring that these critical interconnections are harmonious, mutually beneficial, healthy and preserved for future generations. TheNature Lab at Phipps serves the latest expression of Phipps’ values, one designed to call attention to the importance of providing healthy learning environments for children.

The Nature Lab finds its source of beauty in the elegance of transparency. With its energy-generation and water-capture equipment exposed for guests to see and interact with, the classroom’s inner workings are designed to put education and discovery first. The glow of abundant natural daylight and the inclusion of a living plant wall of plants help tie the importance of biophilic design to the building’s overall efficiency strategies. Beyond the building’s front deck and walkway, a rain garden showcases native plants while contributing to the project’s net zero water goals.

As part of the larger campus it shares with the Center for Sustainable Landscapes, the Nature Lab shows how an elegant, efficient relationship can be established through multiple buildings and a shared landscape, with the intention of inspiring others to mount similar projects at the community scale. Phipps’ next project, an Exhibit Staging Center designed to certify under the Living Building Challenge, as well as LEED Platinum and WELL Platinum, will begin construction soon. Upon completion of the Exhibit Staging Center, anticipated in 2018, Phipps will have three buildings on its campus designed to Living Building standards, each showcasing a different construction type (new, modular and retrofit) – all designed to maximize beauty, and all on display for the engagement of Phipps’ 400,000-plus annual visitors.


Through talks and presentations, docent-led tours and dynamic science education programs, the Nature Lab brings a new nucleus for learning to the Phipps campus. As one of two principal sites for Phipps’ science education programs for ages 2 – 13, the Nature Lab hosts a variety of fun and engaging programs that explore ecology, conservation, healthy living and art through hands-on activities. For six weeks each summer, the Nature Lab becomes the home base of Learning for a Greener Future, a paid internship in which high school students who come from low-income communities gain knowledge in the areas of plant science, environmental issues, sustainability, vegetable gardening and green careers. Graduates of Learning for a Greener Future return to Phipps on Saturdays throughout the year to host guided walk-in tours of the building’s amazing features for the visiting public.

The Nature Lab and the Center for Sustainable Landscapes both seek to inspire replication by others, and the Nature Lab advances this goal in two significant ways. First, the small, self-contained nature of the Nature Lab allows it to serve as a simpler microcosm of the CSL; by presenting the energy efficient HVAC, rooftop solar panels, and water collection tank in such a direct, immediate way, the Nature Lab conveys concepts like net-zero energy and net-zero water which are easily understood by a broad array of visitors. Secondly, because the Nature Lab is designed as a modular, replicable facility, schools and other community assets can easily visualize adding such a structure to their own sites; in fact, subsequent to their collaboration on the Nature Lab at Phipps, designers the SEED collaborative and fabricator EcoCraft Homes formed a partnership for EcoCraft to become the SEED Collaborative’s official East Coast manufacturing partner.

As it does with the CSL, Phipps and its university partners also expect to conduct research around the Nature Lab at Phipps, using a the building as a model to conduct studies on child development, cognition, occupational health, biophilic design, environmental education and many other topics.

Project website: