How Zoning Changes Led to 700+ Affordable Units: Affordable Housing Overlay with Sumbul Siddiqui
How Cambridge Added 700+ Affordable Housing Units with Zoning Reform
Why this episode matters
When most people think of Cambridge, Massachusetts, they think of Harvard, MIT, and innovation. But behind the prestige is a housing market that is out of reach for many families who keep the city running. In this episode of the Affordable Housing & Real Estate Investing Podcast, Kent Fai He sits down with Sumbul Siddiqui, former Mayor and current City Councillor of Cambridge, to unpack how zoning reform and the Affordable Housing Overlay (AHO) spurred over 700 affordable rental units in just a few years
For investors, developers, and advocates, this is a masterclass in how policy, persistence, and community engagement can unlock supply in one of the toughest real estate markets in the country.
What is the Affordable Housing Overlay in Cambridge?
The Affordable Housing Overlay is a zoning tool designed to make it easier and faster to build 100% affordable projects.
Developers can exceed normal height limits by 5 to 85 feet depending on location.
Projects bypass the planning board approval process, cutting years of delay and litigation risk.
Developers must host community meetings and complete a design review but can move to construction much more efficiently.
By reducing risk, adding density, and speeding approvals, Cambridge created a climate where nonprofit developers could confidently bring forward new proposals.
How did the Affordable Housing Overlay create 700+ units?
Since the AHO passed in October 2020, developers have proposed over 700 affordable units across Cambridge, including projects of 100–200 units each.
Notably, new projects are beginning to appear in neighborhoods that historically had little affordable housing, spreading opportunity more evenly across the city.
For affordable housing developers, the overlay reduced three major risks:
Financial Risk: More density means more rent revenue to cover debt service.
Time Risk: Faster approvals reduce carrying costs and speculation.
Legal Risk: Avoiding lengthy planning board processes minimizes lawsuits and appeals.
Who actually lives in affordable housing?
A major myth around affordable housing is that it serves “those people.” Sumbul, who grew up in Cambridge affordable housing herself, pushes back with data and lived experience.
Households must earn below 100% of Area Median Income (AMI) to qualify.
At least 50% of units are reserved for households below 80% AMI.
Residents include teachers, EMTs, bus drivers, social workers, and public-interest attorneys.
Affordable housing is workforce housing. It allows the very people who keep cities functioning to live where they work.
How Cambridge funds its Affordable Housing Trust
The Cambridge Affordable Housing Trust plays a central role. Established in 1989, it funds projects through:
Linkage fees: Commercial developers pay $33 per square foot on projects over 30,000 sq. ft.
Community Preservation Act (CPA): A 3% property tax surcharge matched by state funds.
City operating budget: Cambridge dedicates general fund dollars directly to affordable housing.
Inclusionary zoning: Market-rate developers must set aside 20% of residential floor area for affordable units.
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This diversified funding ensures consistent resources for new construction and preservation.
Key Insights from Sumbul Siddiqui
Zoning is leverage: Changing zoning rules can be just as powerful as securing funding.
Leadership matters: Passing AHO required a pro-housing majority and persistence against NIMBY opposition.
Narrative is key: Explaining who lives in affordable housing humanizes the debate and builds support.
Budgets reflect values: Cities that dedicate general fund dollars to affordable housing send a clear signal about priorities.
Case studies inspire others: Cambridge’s success provides a roadmap for cities nationwide.
Best Quotes
“If developers build 100% affordable units, they can exceed normal height limits by between five and 85 feet.” – Sumbul Siddiqui
“Right now developers have proposed affordable housing projects totaling more than 700 rental units.” – Sumbul Siddiqui
“Budgets are moral documents. Cambridge decided to use our operating budget to fund affordable housing.” – Sumbul Siddiqui
“Affordable housing residents are your bus drivers, EMTs, teachers, and social workers. They are the workforce keeping our city alive.” – Sumbul Siddiqui
Common Questions This Episode Answers
What is the Affordable Housing Overlay in Cambridge?
It’s a zoning reform that lets 100% affordable projects build taller, denser, and with faster approvals, cutting years of delay.
How many units has it produced so far?
Since 2020, developers have proposed over 700 affordable rental units, with several large projects already underway.
Who qualifies for these units?
Households earning below 100% of AMI, with half of units reserved for families below 80% AMI. These include teachers, EMTs, and social workers.
How is affordable housing funded in Cambridge?
Through linkage fees on commercial development, CPA funds, city budget allocations, and inclusionary zoning.
Why do some neighbors oppose these projects?
Common concerns include “neighborhood character” and density, but much of it stems from misinformation about who lives in affordable housing.
Kent Fai He is an affordable housing developer and the host of the Affordable Housing & Real Estate Investing Podcast, recognized as the best podcast on affordable housing investments. Each week, he brings on developers, policymakers, and investors to share real-world strategies that move the needle on housing supply.
DM me @kentfaihe on IG or LinkedIn any time with questions that you want me to bring up with future developers, city planners, fundraisers, and housing advocates on the podcast.
