flexiblefullpage -
billboard - default
interstitial1 - interstitial
catfish1 - bottom
Currently Reading

Conversions of multifamily dwellings to ‘mansions’ leading to dwindling affordable stock

MFPRO+ Research

Conversions of multifamily dwellings to ‘mansions’ leading to dwindling affordable stock

New York City has lost more than 100,000 homes since 1950 to conversion projects.


By Peter Fabris, Contributing Editor | September 11, 2023
Image by David Mark from Pixabay
Image by David Mark from Pixabay

Small multifamily homes have historically provided inexpensive housing for renters and buyers, but developers have converted many of them in recent decades into larger, single-family units. This has worsened the affordable housing crisis, say researchers.

These buildings, commonly called “triple-deckers, two-flats, or brownstones,” provide historical context and add character to urban neighborhoods along with affordability. Nationwide, low-cost rentals have vanished by more than half a million units per year between 2014 and 2018, according to a report from the Harvard Joint Center for Housing Studies (JCHS). New York City alone, lost more than 100,000 homes since 1950 due to conversions of multifamily buildings into single-family “mansions,” according to a report by Dwell.

Many of these buildings supply what is termed “naturally occurring affordable housing (NOAH)”—unsubsidized units rented at relatively low rates. A 2021 McKinsey report found that NOAHs constitute the nation’s largest category of affordable housing units, and that has prompted legislative action to preserve them in some cities.

For instance, in 2021 Chicago’s city council passed two ordinances to discourage developers from eliminating NOAH in two neighborhoods. Developers face up to $15,000 (or $5,000 for each lost unit) for tearing down or converting multifamily buildings.

Preserving older NOAHs takes more than laws, though, it requires someone to spend money to keep them in working order. According to a recent JCHS report, the median unit in small multifamily structures was built 54 years ago. That’s nine years older than the typical single-family home. NOAHs also “face significantly higher quality and structural issues” than your average single-family house, the JCHS report says.

Related Stories

MFPRO+ News | Mar 1, 2024

Housing affordability, speed of construction are top of mind for multifamily architecture and construction firms

The 2023 Multifamily Giants get creative to solve the affordability crisis, while helping their developer clients build faster and more economically. 

MFPRO+ Research | Feb 28, 2024

New download: BD+C's 2023 Multifamily Amenities report

New research from Building Design+Construction and Multifamily Pro+ highlights the 127 top amenities that developers, property owners, architects, contractors, and builders are providing in today’s apartment, condominium, student housing, and senior living communities.

MFPRO+ Research | Feb 27, 2024

Most competitive rental markets of early 2024

The U.S. rental market in early 2024 is moderately competitive, with apartments taking an average of 41 days to find tenants, according to the latest RentCafe Market Competitivity Report.

Student Housing | Feb 21, 2024

Student housing preleasing continues to grow at record pace

Student housing preleasing continues to be robust even as rent growth has decelerated, according to the latest Yardi Matrix National Student Housing Report.

Multifamily Housing | Feb 14, 2024

Multifamily rent remains flat at $1,710 in January

The multifamily market was stable at the start of 2024, despite the pressure of a supply boom in some markets, according to the latest Yardi Matrix National Multifamily Report.

Industry Research | Feb 8, 2024

New multifamily development in 2023 exceeded expectations

Despite a problematic financing environment, 2023 multifamily construction starts held up “remarkably well” according to the latest Yardi Matrix report.

Industry Research | Jan 31, 2024

ASID identifies 11 design trends coming in 2024

The Trends Outlook Report by the American Society of Interior Designers (ASID) is the first of a three-part outlook series on interior design. This design trends report demonstrates the importance of connection and authenticity.

Apartments | Jan 26, 2024

New apartment supply: Top 5 metros delivering in 2024

Nationally, the total new apartment supply amounts to around 1.4 million units—well exceeding the apartment development historical average of 980,000 units.

Adaptive Reuse | Jan 23, 2024

Adaptive reuse report shows 55K impact of office-to-residential conversions

The latest RentCafe annual Adaptive Reuse report shows that there are 55,300 office-to-residential units in the pipeline as of 2024—four times as much compared to 2021.

Multifamily Housing | Jan 15, 2024

Multifamily rent growth rate unchanged at 0.3%

The National Multifamily Report by Yardi Matrix highlights the highs and lows of the multifamily market in 2023. Despite strong demand, rent growth remained unchanged at 0.3 percent.

boombox1 - default
boombox2 -
native1 -

More In Category


MFPRO+ Special Reports

Top 10 trends in affordable housing

Among affordable housing developers today, there’s one commonality tying projects together: uncertainty. AEC firms share their latest insights and philosophies on the future of affordable housing in BD+C's 2023 Multifamily Annual Report.



halfpage1 -

Most Popular Content

  1. 2021 Giants 400 Report
  2. Top 150 Architecture Firms for 2019
  3. 13 projects that represent the future of affordable housing
  4. Sagrada Familia completion date pushed back due to coronavirus
  5. Top 160 Architecture Firms 2021