More than 150 multifamily projects were constructed under the 1955 Mitchell- Lama housing program, including the Tracey Towers in the Bronx, N.Y. This project only exemplifies the type and age of buildings that may be included in the RetrofitNY initiative; no specific list of RetrofitNY projects was available at the time of this article's publication.
Flickr user Dan DeLuca via a Creative Commons license More than 150 multifamily projects were constructed under the 1955 Mitchell- Lama housing program, including the Tracey Towers in the Bronx, N.Y. This project only exemplifies the type and age of buildings that may be included in the RetrofitNY initiative; no specific list of RetrofitNY projects was available at the time of this article's publication.

New York has an ambitious goal to cut its greenhouse gas emissions by 80 percent from 2012 levels by 2050. But how will the state reach that goal? The 40 percent of emissions that comes from building operations won’t be curbed by new, energy-efficient projects alone. “Roughly three-quarters of buildings that will exist in 2050 exist today,” says Greg Hale, senior adviser to the chairman of energy and finance at the state governor’s office. “You have to get at the existing building stock to have any chance of meeting the climate goals.”

RetrofitNY is one initiative aiming to nurture a market for radically improving the performance of existing buildings, starting with a pleasantly surprising typology: affordable housing. Co-led by Hale, the program’s centerpiece is an ongoing design/build competition for retrofits that can cut energy use by upwards of 70 percent, and that are attractive, quick, inexpensive, and replicable.

Expected to kick off in 2017, the competition is open to any firm or team capable of designing, building, and installing the retrofit. The program’s organizers, which include representatives from several state agencies, will identify specific affordable housing properties in need of renovation and set objectives in energy performance, cost effectiveness, aesthetics, and tenant comfort. A jury will review the proposals and select a group of finalists. These finalists will then be asked to present their solutions to each other and refine them based on shared information, says Loic Chappoz, a project manager at the New York State Energy Research & Development Authority (NYSERDA). The hope is that several years of competition and feedback will lead to truly innovative approaches that can be implemented at a large scale.

RetrofitNY will identify ways to finance retrofits based on long-term energy savings and to address regulatory roadblocks. NYSERDA and its partner housing agencies will monitor the performance of the projects over time and publish results. “It’s not going to be a one-off pilot that’s complex and never gets done again,” Chappoz says. “Subsequent rounds will be about improving the solution that was first implemented.”

The competition was announced in January 2016 as one of the cornerstones of Governor Andrew Cuomo's comprehensive clean energy plan, “Reforming the Energy Vision.” The full initiative, which has a budget of $30 million over 10 years and was approved by the New York Department of Public Service in August, cuts across several state agencies and is part of NYSERDA’s $5.3 billion Clean Energy Fund. Although these pilot retrofits will be publicly subsidized, the ultimate goal is to build a self-sustaining market using the state’s 1.7 million affordable housing units as an economic lure.


A side-by-side illustration of an existing building (left) and the retrofit (right), as part of the Energiesprong program in the Netherlands. The renovated house features a new insulated façade, insulated roof, and an exterior mechanical room.
Ian Shapiro A side-by-side illustration of an existing building (left) and the retrofit (right), as part of the Energiesprong program in the Netherlands. The renovated house features a new insulated façade, insulated roof, and an exterior mechanical room.

RetrofitNY is inspired by an ambitious Dutch initiative called Energiesprong, or “energy leap.” Launched in 2010, the government-funded, not-for-profit market development program has transformed the Netherlands’ existing public housing stock into net-zero energy buildings.

Typically, such an extensive transformation is complex, time-consuming, and intrusive. But Energiesprong gives houses visible face lifts while drastically improving energy efficiency within a matter of days. It doesn’t directly build or finance projects, but rather negotiates contracts between housing providers, residents, and contractors. “Their role is as a catalyst,” says Ian Shapiro, founder of green-building consulting firm Taitem Engineering, in Ithaca, N.Y., who researched the program in the Netherlands for NYSERDA.

Energiesprong focuses on public housing—known as social housing in Europe—which offers a large inventory of relatively homogeneous building stock that is in need of upgrades. Social-housing agencies finance retrofits based on the long-term energy savings: Tenants agree to pay an energy surcharge comparable to their normal utility bill to the housing agency, which is used to repay the loan to cover the improvements. Companies performing the retrofit must guarantee net-zero performance up to a specified level of energy usage by the occupant for the 30- or 40-year lifetime of the retrofit.

An existing four-story building (left, background) as compared to a renovated building (right, foreground). The overall treatment is similar to that for a typical two-story building: new façade, roof, solar photovoltaic panels on the roof, and new HVAC equipment housed in exterior mechanical rooms.
Ian Shapiro An existing four-story building (left, background) as compared to a renovated building (right, foreground). The overall treatment is similar to that for a typical two-story building: new façade, roof, solar photovoltaic panels on the roof, and new HVAC equipment housed in exterior mechanical rooms.

The program challenged the construction industry to come up with ways to retrofit groups of social housing units economically and with minimal disruption to occupants. The best ideas were refined based on sharing knowledge among competitors before being piloted.

Contractors participating in the program have found diverse solutions, but they must provide the retrofit as an integrated package that can be mass produced. Many proposals have included laser-scanning each building and then building a custom exterior shell in an off-site factory using prefabricated insulated panels with integrated siding—similar to like exterior insulating systems, or EIFS—and including energy-efficient windows and doors. The new envelope is so tight that all energy needs “can be fully met by solar on the roof,” Shapiro says.

New heat pumps, ventilation units, and hot-water storage tanks are installed in small outdoor sheds. Any gas heating is converted to electric. To entice tenants to participate (Dutch law requires at least 70 percent of tenants in a multifamily-housing building to approve the retrofit), contractors also offer to update kitchens, bathrooms, and landscaping. “It’s this very dramatic, transformational package,” Shapiro says.

Another renovated building project as part of the Netherlands' Energiesprong initiative.
Ian Shapiro Another renovated building project as part of the Netherlands' Energiesprong initiative.
A renovated multifamily housing building with exterior mechanical rooms. The Energiesprong program retrofits often include new landscaping.
Ian Shapiro A renovated multifamily housing building with exterior mechanical rooms. The Energiesprong program retrofits often include new landscaping.
A look inside an exterior mechanical room, showing a heat pump (at left and lower right), a heat-recovery ventilator (top right), and a solar photovoltaic inverter (at right on the door).
Ian Shapiro A look inside an exterior mechanical room, showing a heat pump (at left and lower right), a heat-recovery ventilator (top right), and a solar photovoltaic inverter (at right on the door).

Of the 111,000 units from which the program has secured commitments to renovate, several hundred retrofits have been completed. Earlier this year, the European Commission awarded €3.6 million (about $3.8 million) to Energiesprong UK, a spinoff consortium, to bring the approach to the United Kingdom and France.

Of course, New York is different from Europe. Shapiro points out that Dutch public housing is dominated by two-story row houses that are relatively uniform in design—making it easier to repeat solutions—and topped by gable roofs that make ideal hosts for solar panels. On the other hand, New York’s affordable housing is more diverse: It includes high-rises, tenement walk-ups, row houses, and adaptive reuse buildings such as former schools. Political and financial structures are different. And because energy is more expensive in Europe, a retrofit there creates more future savings with which to finance it.

That’s why, Hale says, the goal of RetrofitNY is not to replicate the Dutch initiative in its entirety. “It’s really a process,” he says. “It’s a way of arriving at a technical solution that works for a place.”

Modular wall sections, delivered and ready for installation.
Ian Shapiro Modular wall sections, delivered and ready for installation.
An insulated roof section with integrated structural rails for solar photovoltaic panels is set into place by crane, as part of the Energiesprong retrofits.
Ian Shapiro An insulated roof section with integrated structural rails for solar photovoltaic panels is set into place by crane, as part of the Energiesprong retrofits.
New solar photovoltaic modules cover the roof area of a renovated project in the Netherlands.
Ian Shapiro New solar photovoltaic modules cover the roof area of a renovated project in the Netherlands.


Beyond environmental goals, preserving existing public and subsidized housing is a major priority for New York State’s housing agencies. “A lot of these buildings were built from the ’60s to late ’70s during the Great Society movement,” says Karen Phillips, director of development for multifamily programs at New York State Homes and Community Renewal. They include more than 150 multifamily housing projects constructed in New York City, Albany, Rochester, and other cities and towns under New York’s Mitchell-Lama Housing Program. In those days, she says, designers used then-novel structural technologies, such as precast concrete curtainwalls, but energy efficiency was not a priority.

Now, after decades of neglect, the buildings are plagued with water and air infiltration, and interior temperatures are not well controlled, Phillips says. “We call it ‘project heat’—when it’s so hot that you see people opening windows [in the winter] to regulate it.”

Philips would like to see some of the same creativity that went into designing these buildings directed into preserving them. Many have had upgrades over the years, but a comprehensive, deep-energy retrofit akin to Energiesprong could extend the life of these buildings much further. In his 2016 State of the State report, “Built to Lead,” Governor Cuomo has pledged to bring deep-energy retrofits to 100,000 affordable housing units by 2025.

A dashboard for tenants to access their energy use.
Ian Shapiro A dashboard for tenants to access their energy use.
Dutch law requires that the renovated buildings provide nesting places for bats and certain species of birds that benefit the natural ecosystem.
Ian Shapiro Dutch law requires that the renovated buildings provide nesting places for bats and certain species of birds that benefit the natural ecosystem.

Retrofitting a building is more a forensic process than a design one, says Ilana Judah, Intl. Assoc. AIA, principal and director of sustainability at FXFowle Architects, in New York. The former often involves piecing together incomplete plans and documentation, understanding the “DNA of the building,” and finding interesting design elements to build on. “In many instances, we don’t give enough importance to retrofits as architects,” she says. If the RetrofitNY competition emphasizes both creative and technical design solutions, she hopes that kind of thinking could be changed.

Encasing an older building with an airtight envelope can seem daunting, but it’s more attainable than most people would think, says Michael Ingui, AIA, principal at New York firm Baxt Ingui Architects, which is completing several market-rate townhouse retrofits expected to reach Passive House standards. Ingui hopes that RetrofitNY will show more architecture firms how cost effective this kind of undertaking can be, and that an increased demand will help spur a bigger supply chain for energy-efficient building materials, like insulated wall panels and high-performance glazing. “It’s a whole market that can open up,” he says.

Note: This article was updated to clarify that the budget for RetrofitNY is $30 million over 10 years, and is part of NYSERDA's $5.3 billion Clean Energy Fund.