100 Amity Street (Polhemus Residences)

Per press coverage of the conversion, the two main façades were kept almost entirely intact, the secondary façades were rebuilt in matching brick, the railings and copper cornice were restored, and a mid-century bridge to the hospital building across Henry Street was removed. The Commission approved the exterior changes unanimously in 2015 and refused new balconies.

Inside, the clinic was built around stacked double-height lecture and clinical halls. The conversion took these out and inserted a new elevator-and-stair core in the gap. The residences wrap around it, leaving a ring of original structure on the perimeter. The oversized windows that once lit the teaching halls now set the proportions of the living rooms. The original floors had to be removed, and coverage of the project identifies them as an early Roebling concrete fireproof floor system. The hipped, skylit top floor was flattened to make room for the roof deck.

The residences are numbered 1 through 15 plus two penthouses. Per the offering plan's Schedule A, they total roughly 39,800 square feet, with terraces, roof decks and balconies as limited common elements. Layouts vary widely because every floor had a different original plan. Buyers comparing two residences here should compare plans rather than lines.

Management and staffing. The offering plan provides for professional management with a concierge desk. The plan also anticipates access fees from the homeowners association for its use of the condominium's amenities. The same association runs the parking. Confirm the current terms of the shared-facilities agreement between the two entities.

Sponsor position. The sponsor closed its first sale in December 2018 and sold most of the residences by August 2019, with further closings in 2020 and 2022. The 2027 Department of Finance roll still shows one residence (lot 1202) owned by the sponsor entity. A second residence is held by an LLC that joined the sponsor on a 2020 mortgage recorded against both units. ACRIS also shows the condominium recorded liens for unpaid common charges against both of those units, in April 2022 and June 2023. No release of either lien appears in ACRIS. A buyer should ask the managing agent whether those arrears were cured.

For-sale position. The other 15 residences were sold to separate, unrelated buyers. All 17 lots are classed as residential condominium units on the city roll, and none carries the city's condominium-rental class. There is no rental block inside the condominium.

Temporary certificate of occupancy. The building is still operating under a temporary certificate of occupancy. That certificate has been renewed about every three months since 2018, and there is still no final certificate. Some lenders ask for evidence of TCO renewal or a sponsor commitment to obtain the final certificate. Ask for the current TCO and the list of open DOB items.

Recent sales

Recent closings at this building, from The Roebling Research Library. Prices are the transfer amounts recorded with the NYC Department of Finance; apartment-level detail is checked against the building’s own file in The Roebling Research Library before publishing.

Market read. Most recent trades (2026 to date) cleared a median $1,922/sf (recorded) across 1 sale. Median listing discount 0.0% from the last ask.

Sales sourced from NYC Department of Finance recorded transfers (BBL 3-00295-7502; each condominium apartment is its own tax lot). Apartment-level facts (line, condition, asking-price context) curated and cross-verified in The Roebling Research Library. Not all transactions cross-verify with ACRIS records — sponsor and LLC purchases sometimes record at stipulated values rather than market price; square footage from recorded condo declarations and offering plans.

Read the homeowners-association documents with the condominium's. Parking and part of the amenity cost-sharing run through a separate association. Your counsel should review its budget, its fee to owners, and how it governs the parking facility.

Clear the TCO and the sponsor liens early. Both are covered above. Put the lender and your attorney on them at contract, not at commitment.

Expect landmark review for exterior work. Any work visible from the street, including window replacement, needs LPC approval because the building sits in the Cobble Hill Historic District Extension.

If you're considering Polhemus Residences, also evaluate:

• The Cobble Hill House (78 Amity Street): separate new-construction condominium on the same block; the low-rise ground-up alternative with deeded parking
• 5 River Park (347 Henry Street): new-construction condominium on the former LICH campus across Amity Street
• The Arches at Cobble Hill (401 Hicks Street): condominium conversion of a nineteenth-century parish complex inside the historic district
• 501 Hicks Street (Cobble Hill School Condominium): an institutional building converted to condominiums
• Cobble Heights (174 Pacific Street): an 1888–89 public school converted to a co-op, inside the historic district
• Cobble Hill Towers (439 Hicks Street): landmark model-housing blocks, now a condominium
• One Clinton (1 Clinton Street): new-construction Brooklyn Heights condominium; the full-service peer