What Xenolith Partners does

Xenolith Partners LLC is a privately held, woman-owned (WBE/MBE) affordable housing real estate developer founded in 2016 by Andrea Kretchmer and Terri Belkas-Mitchell. Headquartered in New York with a Connecticut office, the firm develops affordable, mixed-income, mixed-use, supportive, and senior housing projects across New York and Connecticut. Its portfolio includes Casa Celina (205 units, $113MM), The Rise (72 units, NYSERDA Buildings of Excellence), Columbus Commons (80 units, Passive House certified), Stanley Commons (240 units), Coney Island Commons (195 units), Bayshore Senior Residence (76 units), Lebechi East (95 units under construction), The Iron (279 units in development with Gilbane), and the recently awarded La Ostra (600+ units on the Inwood waterfront with Slate Property Group and Comunilife). Co-founder Terri Belkas-Mitchell has helped secure over $300 million in construction financing across eight projects totaling more than 750 units.

Name

Xenolith Partners

Legal name

Xenolith Partners LLC

Website

https://xenolithpartners.com

Company type

Private

Founded year

2016

Operating status

Operating

Headcount range

1–10 employees

Short description

Xenolith Partners is a woman-owned affordable housing developer that builds Passive House-certified, supportive, and mixed-income rental housing across New York and Connecticut for low-income seniors, homeless, and special-needs populations.

Ownership category

akta.pro rank

Product category

Affordable Housing Development

NAICS

New Multifamily Housing Construction (except For-Sale Builders) (236116), Continuing Care Retirement Communities and Assisted Living Facilities for the Elderly (6233), Residential Intellectual and Developmental Disability, Mental Health, and Substance Abuse Facilities (6232)

SIC

Land Subdividers & Developers (No Cemeteries) (6552), Real Estate Agents & Managers (For Others) (6531)

akta.pro primary industry

Affordable Housing & Community Development (Housing, Community Land Trusts) (BPAGALAC)

akta.pro secondary industries

Affordable & Subsidized Housing Property Management (LIHTC, Section 8) (BPAJAFAD), Affordable/Subsidized Independent Living (HUD/LIHTC) Communities (HLADAAAB)

Keywords

• Affordable housing development
• Mixed-income housing
• Supportive housing services
• Passive house construction
• Brownfield remediation

Headquarters

HQ city

New York

HQ country

United States

HQ region

North America

Offices3 records

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Operations, Infrastructure, Technology or R&D, Marketing or Sales

Revenue model

1. Affordable Housing Development Fees: Xenolith Partners generates revenue through development fees earned on affordable housing projects. As a developer, they earn fees from successfully completing projects, typically financed through a combination of conventional debt, LIHTC (Low Income Housing Tax Credits), HCR funds, and deferred developer fees. Terri Belkas-Mitchell has helped secure over $300 million in construction financing across eight different projects.

Go-to-market motion1 record

Distribution channels3 records

Marketing channels4 records

Core offering

Xenolith Partners LLC is a woman-owned affordable housing development company that develops mixed-use, mixed-income, and supportive housing projects across New York and Connecticut. The firm secures projects via government RFPs from agencies including NYC HPD, NYCHA, NYS HCR, and municipal authorities, then develops affordable, senior, supportive, and transit-oriented housing using complex financing structures combining LIHTC, government subsidies, and conventional debt. The portfolio includes senior housing, supportive housing for justice-involved and homeless populations, and historic adaptive reuse projects built to Passive House sustainability standards.

Product overview

Xenolith Partners LLC is a woman-owned affordable housing development company that creates mixed-use, mixed-income, and supportive housing projects across New York and Connecticut. The company develops individual real estate projects including senior housing (Casa Celina, Bayshore Senior Residence), supportive housing for vulnerable populations (The Rise, Lebechi East, Harbor House at the YWCA), community-oriented developments with YMCA and community facility spaces (Coney Island Commons, Stanley Commons), transit-oriented developments (Columbus Commons, The Iron), and historic adaptive reuse projects (Threadmill Apartments). The portfolio spans over a dozen completed and ongoing projects totaling over 1,500 housing units.

Differentiator

Problem solved

Functional benefit

Products and services

• Casa Celina 16-story, 205-unit affordable senior housing development in the Bronx featuring all-electric design with Cold Climate Heat Pumps, solar arrays, and community facility space for JASA services. Named for Celia Baez, mother of Supreme Court Justice Sonia Sotomayor. Completed October 2023.
• The Rise - Vital Brooklyn Site J 72-unit supportive and affordable housing development in Brownsville, Brooklyn featuring community facility space, OBHS administrative space, and rooftop green space. Passive House certified with all-electric design. Completed November 2024.
• Columbus Commons 80-unit mixed-income housing project in downtown New Britain, CT near CTfastrak transit station. Passive House certified, second mixed-use multi-family Passive House in Connecticut.
• Bayshore Senior Residence 76-unit senior LGBT-friendly affordable housing development on Long Island with community facility operated by LGBT Services Network. Launched June 2021.
• Coney Island Commons 195-unit, two-building affordable housing complex in Brooklyn with 42,500 SF YMCA featuring aquatic center, gymnasium, and fitness facilities. Won 2014 Building Brooklyn Award. Cost $79MM.
• Stanley Commons 240-unit, six-building affordable housing complex in Brooklyn's East New York neighborhood with 19,000 SF community facility for social services. Cost $72.4MM.
• Park and Elton Apartments 38-unit mixed-income housing development in two buildings in the Bronx Melrose neighborhood with LEED-equivalent sustainable design. Launched January 2021.
• The Iron - New Haven 279-unit mixed-income project in New Haven, CT with 25% affordable units, retail space, community facility, and underground parking. Cost $100MM+.
• Lebechi East 95-unit supportive and affordable housing project in Brooklyn with 5,000 SF community facility offering health services. 60% supportive units for those with Severe Mental Illness, Substance Use Disorder, and HIV/AIDS. Cost $51.5MM.
• Harbor House at the YWCA 54 supportive housing units new construction plus historic substantial rehabilitation of existing 42-unit SRO building in Schenectady, NY. Developed in partnership with YWCA NorthEastern NY.
• Threadmill Apartments 58-unit adaptive reuse of historic textile mill in Stonington, CT with 9,000 SF retail space. National Register of Historic Places registered property. Cost $24.6MM.
• Belmont Venezia 177-unit project-based Section 8 portfolio in the Bronx with moderate rehabilitation including roof, heating, hot water, and window replacements.

Quantifiable outcome

• Over $300 million in construction financing secured for 750+ units across 8 projects
• +3 more outcomes

Named customers5 records

Segments5 records

Ideal customer profiles2 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Partnerships

17 partnerships are on record, tiered core.

• Slate Property GroupcoreStrategic or Co-development Partner · 10 December 2025Co-developer with Xenolith Partners and Comunilife selected by the city to develop the La Ostra project - over 600 affordable housing units on Inwood waterfront with marine science center and sports facilities
• ComunilifecoreStrategic or Co-development Partner · 10 December 2025Co-developer with Slate Property Group and Xenolith Partners selected by the city for the La Ostra affordable housing project in Inwood, Manhattan
• Gilbane Development CompanycoreStrategic or Co-development Partner · 1 July 2024Gilbane Development Company and Xenolith Partners were awarded the opportunity to develop Site A-1 'The Iron' in New Haven through the City of New Haven's 'State and George' RFP. The Iron is a 279-unit mixed income project valued at $100MM+.
• Women's Prison Association and Home (WPA)coreStrategic or Co-development PartnerWPA is the supportive services provider and co-developer partner for The Rise development. They provide case management, job-readiness training, job placement, and legal assistance for justice-involved residents.
• Brownsville PartnershipcoreStrategic or Co-development PartnerCommunity Solutions/Brownsville Partnership is a co-development partner for The Rise project, working to revitalize the Brownsville community through supportive housing.
• Magnusson Architecture and Planning (MAP)coreImplementation/ SI/ Consulting PartnerMAP serves as project architect for multiple Xenolith developments including The Rise and Casa Celina. They provide architectural design and planning services for the firm's affordable housing projects.
• Bright PowercoreImplementation/ SI/ Consulting PartnerBright Power provides energy-focused and Passive House consulting for Xenolith's developments, including The Rise, ensuring buildings meet Passive House certification requirements.
• The Osborne AssociationcoreStrategic or Co-development PartnerThe Osborne Association provides supportive services for The Rise residents, offering services for re-entry transition and development of social and wellness skills alongside WPA.
• Family Services Network of New York, Inc. (FSNNY)coreStrategic or Co-development PartnerFSNNY is a 501(c)3 health services provider collaborating with Xenolith on Lebechi East development. FSNNY will operate a 5,000 SF ground-floor community facility offering health services to the public, including services for those with SMI, SUD, and HIV/AIDS.
• The Kretchmer Companies LLCcoreStrategic or Co-development PartnerAndrea Kretchmer was a founding principal of The Kretchmer Companies before forming Xenolith. The two firms continue to partner on developments including Casa Celina.
• ELH Mgmt. LLCcoreStrategic or Co-development PartnerELH Mgmt. LLC is a co-developer partner on Casa Celina and was involved in Coney Island Commons. They manage the Casa Celina leasing lottery.
• Jewish Association Serving the Aging (JASA)coreStrategic or Co-development PartnerJASA is a joint venture partner on Casa Celina, providing the East Bronx Case Management Program and social support services and senior health and wellness programming for residents.
• YWCA NorthEastern NYcoreStrategic or Co-development PartnerXenolith Partners is working closely with YWCA NorthEastern NY to redevelop their historic property in Schenectady. Harbor House at the YWCA will include new construction of 54 supportive housing units and historic rehabilitation of existing SRO building.
• Dakota Partners Inc.coreStrategic or Co-development PartnerDakota Partners Inc. is co-developer with Xenolith on Columbus Commons, a $54MM mixed-use development in downtown New Britain, CT that achieved Passive House standards.
• D&F Development Group, LLCcoreStrategic or Co-development PartnerD&F Development Group is co-developer with Xenolith on Bayshore Senior Residence, the first senior LGBT-friendly affordable housing development on Long Island.
• LGBT Services NetworkcoreStrategic or Co-development PartnerLGBT Services Network ('The Network') operates the community facility at Bayshore Senior Residence, providing advocacy, education, support, and development services for LGBT populations.
• One Brooklyn Health System (OBHS)coreOthersOBHS occupies 3,000 SF of administrative space at The Rise development, serving as an anchor tenant that provides health services to the community.

Scale indicators5 records

Recent moves6 records

Expansion highlights5 records

Direct peers

• Monadnock Development: NYC affordable and supportive housing developer with deep NYCHA/HPD relationships and experience with Passive House and sustainable design. Closely comparable on project type, financing structure, and supportive housing specialization.
• Gilbane Development Company: National real estate developer with active affordable housing practice and Xenolith's co-development partner on The Iron project in New Haven. Comparable on mixed-income multifamily development.
• L+M Development Partners: L+M is a major NYC-based affordable and mixed-income housing developer with a comparable LIHTC-financed multifamily portfolio and similar government RFP pursuit model. Directly comparable on business model, target population, and New York metro geography.
• Slate Property Group: NYC affordable housing developer that is also Xenolith's co-development partner on La Ostra (600+ units). Directly comparable on product type, geography, and government RFP pursuit model.
• BRP Companies: NYC-based affordable and mixed-income housing developer with significant LIHTC-financed multifamily portfolio and government RFP pipeline. Comparable scale and product type.
• Dakota Partners Inc. Massachusetts-based affordable housing developer that is Xenolith's co-development partner on Columbus Commons in Connecticut. Comparable on LIHTC-financed multifamily development and government RFP model.
• Phipps Houses: Long-standing NYC affordable housing developer and property manager with comparable LIHTC-financed multifamily portfolio and NYCHA/HPD pipeline. Mission-aligned non-profit model similar in spirit to Xenolith's impact focus.

Emerging players

• Comunilife: NYC non-profit developer and operator of supportive housing that is Xenolith's co-development partner on La Ostra. Comparable on supportive housing specialization and government RFP pipeline, though operates as non-profit operator-developer.
• Habitat for Humanity New York City and Westchester County: Non-profit affordable housing developer in NYC/CT region focused on homeownership and affordable rentals. Comparable on mission and geography but operates a non-profit model versus Xenolith's for-profit WBE approach.

Broad incumbents

• The Related Companies: Large national real estate developer with significant affordable housing practice (Related Affordable). Operates at substantially larger scale across multiple geographies with broader portfolio including market-rate.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks6 records

Key highlights7 records

Customer concentration

• LinkedInlinkedin.com/company/xenolith-partners

Revenue estimate

Valuation estimate

Number of profiles

Profiles4 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Xenolith Partners