Finding new solutions for residential conversion

Three years since the onset of the Covid-19 pandemic, New York City has defied the most dire predictions of urban decline, yet today the city faces new challenges. As the city continues to struggle with an acute housing shortage, 560,000 new residential units will need to be created by 2030 to accommodate a growing population and to make up for a shortfall of construction. At the same time, many commercial real estate owners are saddled with a surplus of vacant office space, as the rise of remote work has led companies to reduce their physical footprints. The effects are especially pronounced for older buildings, which lack up-to-date amenities or may require extensive renovations to meet current market demands.

The climate crisis adds another layer to New York’s built environment conundrum. In a city where living space is at a premium, we cannot afford to let any built space go unoccupied. Neither can we afford to squander the carbon that has been expended in building millions of square feet of now-underused office space.

City leaders have recommended the conversion of underused office spaces to much-needed housing, a concept that has been slow to gather steam for a variety of economic, pragmatic, policy, and design reasons. 1633 Broadway, an aging Midtown office tower completed in 1971, is emblematic of the challenges and opportunities for office-to-residential conversion. Our design proposes a new model for residential development in New York—an innovative approach to adaptive reuse that will help to build a more vibrant, equitable, and sustainable city.

From monolith to diverse vertical village

Like many large mid-century office buildings, 1633 Broadway has vast floor plates with more than 50-foot lease depths, characteristics that make it difficult to convert to residential use. The first step in our design scheme is to selectively remove floor area to reconfigure the floor plates. By strategically carving away vertical portions of the monolithic building volume, we create floor sizes suited to appropriate residential layouts. Cutting away also maximizes perimeter, and therefore access to natural light.

We can then recapture the removed floor area by adding it to the top and the base of the building. This strategy achieves multiple benefits at once: creating a distinctive profile on the skyline, filling in a podium level to house a range of amenities and programs, and producing a staggered roofscape to accommodate a series of garden terraces. 

By repurposing the original structure, we save 50 percent of the embodied carbon invested in the building’s construction. This approach also reduces construction time as compared to ground-up construction. Our concept is an inherently sustainable solution to meet the city’s housing needs, and one that can be financially viable for owners and developers as well, thanks to an innovative programming model that creates uncommon value for residential offerings that serve a range of income levels.

A more equitable model for mixed-income housing

The typical approach to residential development in New York falls far short of meeting the needs of a city in the throes of a historic housing crisis. The economics of development typically favor the creation of luxury housing, with a minimum required amount of affordable units (often 20 percent of total) interspersed throughout the building. Affordable rental units are typically placed on lower floors, with the least-desirable exposures and less natural light, while the higher floors with the best views are reserved for luxury apartments. Social and economic stratification becomes manifest in the form of the building, and the result is often an uneasy compromise for developers, buyers, and tenants alike.

Our concept turns this approach on its head. It puts forward a vision for an equitable city in which all residents, not only the wealthiest, have access to uplifting living spaces—homes with abundant natural light, inviting outdoor terraces, and inspiring views. Exceeding the 12 FAR cap on residential development, this proposal highlights the urgent need to reconsider existing zoning regulations and lift the current cap in order to bring density and housing to those in need.

The retrofit proposal for 1633 Broadway brings together three residential types. The building contains 327 luxury market-rate homes, 380 two-bedroom co-living dwelling units, and 838 micro-affordable apartments, with a total floor-area ratio of 17. Two of the three housing types are innovative typologies to maximize density: the micro affordable apartments are sized smaller than current HPD requirements, and the two-bedroom co-living units provide shared spaces and amenities to accommodate more flexible and short-term housing needs. Rather than the traditional approach of stacking programmatic elements vertically, our design places them side-by-side. In this way, abundant natural light and penthouse views become available for each of these residential types.

Beyond the single-use business district

The advantages of our intensive mixed-use residential concept extend to the surrounding urban realm. By reconfiguring a monolithic commercial office building to provide three distinct residential types, we can condense the vitality of a dense and diverse city within the space of a single block.

The conversion of 2.5 million square feet of commercial space to a mixed-income residential building will have immediate and profound ripple effects on the character and vitality of the surrounding district. This dense new development will spur the creation of services and businesses to meet the needs of a burgeoning residential community: new restaurants, grocery stores, nightlife, and other amenities will accelerate the transformation and revitalization of Midtown Manhattan from a business district to a 24/7 mixed-use neighborhood.

By seizing the potential of vacant office space—and, crucially, making this type of conversion financially viable and attractive for owners and developers—this concept can become a model for reinvigorating business districts to become vibrant and amenity-rich neighborhoods.