NZI on TAP: Philadelphia & Peer Cities Brainstorm Best Practices for Retrofitting Affordable Housing

(ULI)

“NZI on TAP” is a front-row seat to the energy, insights, and actionable recommendations generated during ULI’s Net Zero Imperative Technical Assistance Panels. These panels bring together experts across the real estate value chain to tackle real-world development challenges with sustainability at the core.

ULI Philadelphia and the ULI Net Zero Imperative, in partnership with the City of Philadelphia’s Division of Housing and Community Development (DHCD) and the Philadelphia Housing Development Corporation (PHDC), hosted a two-day technical assistance workshop from May 8-9, 2025, focused on retrofitting existing affordable housing to net zero. The primary goal of the workshop was to create a blueprint for DHCD, PHDC, and others in the affordable housing sector to successfully retrofit projects to achieve carbon neutrality while maintaining affordability. The workshop was structured around three primary questions:

1. How might the city complement gap financing for full rehab projects with options for smaller, more gradual interventions?
2. What training or other support would enable owners of affordable multifamily properties to successfully plan for and implement preservation and decarbonization projects effectively?
3. How does the regulatory environment in peer jurisdictions affect the preservation of affordable housing (both affordability and decarbonization)?

The workshop also centered the panelists’ focus on recommendations that would enable quicker action:

1. Recommendations for structure of offerings of related new initiatives for funding rehabs, and recommended changes to existing financing offerings
2. Capacity-building recommendations to help shape staff support for affordable housing developers within the Department of Planning and Development
3. List of key supportive regulations for the Administration and Council to consider

Workshop Participants
The panelists and workshop participants came from local and regional markets as well as peer cities, including Boston, Pittsburgh, New York, Chicago, and Detroit. Workshop partners assembled a team of practitioners from across the country to present a range of case studies, facilitate conversations, and tour affordable housing developments. The experts shared best practices to preserve affordability and become carbon neutral based on lessons learned in retrofitting multifamily housing stock. The workshop also included administrators from peer cities who have overcome similar challenges in managing their affordable housing portfolios, and who have structured local financing products to leverage other funds to support residential decarbonization:

• Vidhi Anderson, vice president of development, HumanGood—Philadelphia
• Joe Backer, senior development officer, Mayor’s Office of Housing—Boston
• Neil Burger, program manager, Capital Projects Division, Philadelphia Housing Authority—Philadelphia
• Kelly Carry, senior development project Manager, Stone Sherick—Philadelphia
• Mark Dodds, interim deputy director of DHCD, City of Philadelphia—Philadelphia
• Jaclyn Helverson, treasurer, Philadelphia Housing Authority—Philadelphia
• Laura S. Humphrey, senior director of energy and Sustainability, L+M Development Partners—New York
• Nidhi Krishen, deputy director for climate solutions, Office of Sustainability—Philadelphia
• Saundra Malanowicz, program manager, DHCD, City of Philadelphia—Philadelphia
• Naida Elena Montes, Ph.D., CDBG-DR deputy project director, Office of the Director of Finance, City of Philadelphia—Philadelphia
• Stacey Mosley, senior director of development and research, Brandywine Realty Trust—Philadelphia
• Rachel Mulbry, director of Policy and Strategic Initiatives, PHDC—Philadelphia
• Andrew Niemynski, residential program manager, Philadelphia Energy Authority—Philadelphia
• Kenyatta “Ken” Parker, energy program manager, Community Investment Corporation—Chicago
• Alan Razak, senior advisor, AR Spruce—Philadelphia
• Susanne Stone, principal, Stone Sherick—Philadelphia
• David S. Thomas, CEO, PHDC—Philadelphia
• Derrick Tillman, founder amd president, Bridging the Gap Development—Pittsburgh
• Joel Wool, deputy administrator, Boston Housing Authority—Boston
• Evelyn “Evy” Zwiebach, director of policy and programs, Detroit Enterprise Community Partners—Detroit
  

  

  (ULI)

The ULI Net Zero Imperative (NZI) is ULI’s multiyear initiative to accelerate decarbonization in the built environment and advance the organization’s net zero mission priority. Implemented by the ULI Lewis Center for Sustainability in Real Estate in collaboration with ULI District and National Councils and local partners, key activities include Technical Assistance Panels (TAPs), which are intense multi-day engagements during which a panel of ULI member experts and partners help clients or sponsors, often local governments, think through strategies for advancing their net zero goals and priorities. NZI provides grant funding and forms a cohort of cities each year to tackle net zero and building decarbonization challenges in their communities through technical assistance and implementation efforts (e.g. workshops, convenings, case studies, graphic diagrams, etc.). This global cohort meets virtually every month and convenes in-person at ULI Spring and Fall Meetings to learn best practices and avoid potential pitfalls. Insights across the cohorts are distilled and shared via articles, reports, and videos.

Taking Stock

Context is king, and in established markets such as Philadelphia it is crucial to understand the built environment. As one panelist noted, “Philadelphia’s housing stock is overwhelmingly old, small, and residential.” Retrofits that achieve both affordability and net zero goals won’t be easy:

• 88 percent of the housing stock was built before 1980 (more than 45 years old)
• Nearly 40 percent of housing supply was built before 1939
• Nearly half of Philadelphia’s renters and a quarter of its homeowners are cost-burdened
• Philadelphia’s share of energy-burden is 86 percent higher than the national average
• Only four percent of the grid’s electricity comes from renewable energy sources

As the renting population increases, it’s also critical to understand tenants’ ability and motivation to invest in decarbonization and energy efficiency measures. ULI has recently published research on best practices for tenant engagement, which outlines tenant-owner alignment on achieving shared net zero goals.

Preserving Affordability, Reducing Emissions

The dual crises of housing affordability and climate change demand scalable and translatable solutions to create impact. Proactively convening the real estate industry and public sector leadership in these sectors unearthed a series of barriers and pain points that slow progress. While every local market is unique, there are best practices that should be adopted to elevate the baseline and accelerate action. Philadelphia looked to supportive regulations from peer cities to better understand the policy landscape, such as:

1. Boston’s Building Emissions Reductions Disclosure Ordinance (BERDO)
2. New York City’s Local Law 97 Greenhouse Gas Emissions Reduction Requirements (LL97)
3. Detroit’s PILOT Reform Affordable Housing Ordinance

Attention then turned to the evergreen question of funding and financing. Panelists noted an overall retreat of federal resources for affordable housing and decarbonization. State and local sources are attempting to fill the void, but are also under strain. The conversation also focused on the complexity and challenges of pursuing the varying buckets of funding sources, as the patchwork requirements typically do not align well or are bespoke to each source (e.g., LIHTC only accepts limited types of green certification to earn points towards an award). A sampling of the funding sources discussed is summarized in the table below.

(ULI)

Apart from policies and funding, the city will also need to meet with the community to provide additional technical assistance and capacity building to ensure that the uptake of any proposed programs is equitably distributed and adopted into practice. One workshop participant keenly noted that “training developers alone will not change anything... it must also include operators, residents, and asset managers.” Deep local engagement and strong partnerships will help ensure that the community is informed, involved, and championing the changes necessary to meet the moment.

A Collaborative Future

Affordability and decarbonization are not mutually exclusive but do require deep and long-term partnerships to be successful. Solutions exist today in markets that are driving impact, which the expert panelists from the Philadelphia workshop summarized in seven key recommendations:

1. Develop Clear Strategies & Ambitious Priorities
   Leverage the City’s unique, high-level view of the affordable housing landscape to set clear priorities for affordable multifamily preservation and decarbonization.
2. Pursue Impactful Regulation that Builds on Learning From Peer Cities
   The City can influence the market through thoughtful regulation paired with targeted investment.
3. Create a Comprehensive Process Map
   Map out the current affordable housing development process in detail, including timelines and relevant public entities.
4. Streamline the Development Process for Affordable Housing
   Identify areas where consensus among relevant public entities can streamline processes through changes like combining funding applications and setting clear criteria for expediting certain development processes (i.e. building permits, zoning hearings, utility connections).
5. Offer More (Diverse) Funding
   Align affordable housing preservation funding with higher-level City priorities. This should include an exploration of predevelopment and construction lending, and increased gap financing.
6. Provide Affordable Housing Developer Services
   Support developers throughout the process through the creation and staffing of an affordable housing developer services team at DPD.
7. Training
   Ensure that education and training opportunities reach everyone, including building managers, maintenance staff, and residents. This will ensure that decarbonization interventions are successful and sustainable going forward. The process does not end just because construction has been completed.

(ULI)

On October 30, 2025, the detailed NZI TAP report was released to the public during a launch event with facilitated focus group discussions. The report clearly documents the conversations, insights, case studies, peer learnings, and next steps for DHCD and PHDC. The launch of the report coincided with a kickoff of the next phase of the work, due to be completed in 2026. It initiates a conditions analysis of the existing affordable housing stock, estimates the costs of retrofits, identifies existing funding and financing options, and develops strategies for the City to fill potential financial gaps.

Interested in getting involved? Cohort 5 of NZI was recently announced, learn more at ULI.org/NZI. Members and partners can raise their hands to serve as panelists by submitting information through the Net Zero Imperative Technical Advisory Panelist ULI Navigator form. Reach out to [email protected] for more information.

Related Resources

• Announcing the Fifth Cohort of the ULI Net Zero Imperative—Eight Cities Tackling Building Decarbonization
• NZI on TAP: Washington, D.C. Demonstrates Leadership in Net Zero Transit-Oriented Development
• Building Decarbonization: Top 10 Insights from the ULI Net Zero Imperative
• Moving the Net Zero Needle: ULI Net Zero Imperative Advances Building Decarbonization Efforts—Operationalizing ULI’s Net Zero Mission Priority
• ULI Net Zero Imperative Webpage & Program Overview Video
• ULI Net Zero Imperative: Three Years of Accelerating Building Decarbonization