Thornton Park
18 Thornton Street, near Flushing Avenue · Williamsburg
Williamsburg, Brooklyn
BBL 3022767501 · BIN 3392149
- Year built
- 2006
- Type
- Condominium
- Units
- 14
- Floors
- 7
- Amenities
- Elevator; in-unit laundry appears in the apartment inventory
- Landmark status
- Not an individual landmark; not in a historic district
- NYC Landmarks Preservation Commission and City Planning records, updated February 2026
Every recorded sale at this building, 2008–2025
Price-per-square-foot over time, the line- and floor-premium curves, and every recorded sale.
- Median $/sf, 2025
- $661
- floor-adjusted, 1 sale
- Listing discount
- 1.7%
- Recorded sales
- 23
- On record
- 2008–2025
Own an apartment here? See what it would sell for.
A Private Pricing Opinion — what your apartment at Thornton Park would likely sell for today, what it costs to sell, and what you’d walk away with — reviewed personally against condition, exposures, renovation quality, and the competition actually on the market.
Thornton Park is a small elevator condominium built in 2006, with fourteen homes distributed within a seven-story building. Its original apartment mix was unusually clear: ten two-bedroom residences with two bathrooms and four one-bedroom apartments. The two categories remain visible in the resale history.
The building also uses the address 721 Flushing Avenue. It sits near the boundary between Williamsburg and Bedford-Stuyvesant, with the Flushing Avenue commercial corridor immediately alongside it. Both residential and nonresidential lots form part of the condominium.
Architecture and unit composition
The smaller one-bedroom homes have recorded areas around 515 square feet. Two-bedroom apartments generally fall around 950 to 1,000 square feet and include two bathrooms. That is a substantial difference in interior area within a building whose total residential inventory is limited.
The original interiors used open kitchens, including island sinks, stone countertops, wood cabinetry and stainless-steel appliances. Two-bedroom layouts provide a larger living area and an additional bathroom without moving into the scale of a full-floor home. Upper-floor apartments occur in both the smaller and larger categories.
Building operations
Elevator access serves the residential floors. The condominium's DOF roll includes fourteen residential lots and ten nonresidential lots, so the residential count is smaller than the total number of legal condominium interests.
Two different tax programs appear on the property. The 421-a program is the residential benefit; ICIP/ICAP applies to the commercial portion. Their start years differ, and the commercial benefit should not be treated as an additional exemption on a residential apartment.
The largest single owner holds three of the fourteen residences, or approximately 21 percent. The other homes are separately owned, and individual residential transfers have continued over more than a decade.
Local Law 97
This building is below the 25,000 sq ft threshold at which LL97 limits apply to a building on its own. It is still covered if it shares a tax lot or condominium board with buildings totaling over 50,000 sq ft; confirm on DOB’s covered-buildings list.
See full Local Law 97 analysis →Facade safety — Local Law 11
The latest available filing classified the facade as SWARMP — Safe With A Repair and Maintenance Program: the inspector (QEWI) identified conditions requiring monitoring or repair, with repairs due by the deadline stated in the filing. The scope, timeline, and how the building funds the work are building-specific — we review the filings and board materials for you.
How to read this, and where it comes from
QEWI = Qualified Exterior Wall Inspector — a licensed professional engineer or registered architect who meets DOB’s FISP qualifications and signs the report (the independent expert, not the managing agent).
Penalties shown are amounts DOB assessed against filings on record across 2015–20 to 2025–30. The FISP dataset does not record whether they were paid, contested or remain open, so treat the figure as history rather than a current balance and confirm the building’s standing with the managing agent.
Source: NYC DOB facade filings (FISP) · The Roebling Research Library. City data last refreshed October 2026.
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.
| Date | Unit | Apartment | Price | PPSF | vs. Ask |
|---|---|---|---|---|---|
| Jan 31, 2025 | 6C | 2 BR · 2 BA · 990 sf | $790,000 | $798/sf | -12.1% |
| Jul 26, 2024 | 7A | 2 BR · 2 BA · 988 sf | $940,000 | $951/sf | -1.1% |
| Aug 21, 2023 | 6C | 2 BR · 2 BA · 990 sf | $770,000 | $778/sf | — |
| Jul 27, 2022 | 3A | 2 BR · 2 BA · 950 sf | $775,000 | $816/sf | -2.5% |
| Jun 2, 2022 | 5B | 1 BR · 1 BA · 515 sf | $520,000 | $1,010/sf | +4.0% |
| Feb 8, 2022 | 6A | 2 BR · 2 BA · 970 sf | $750,000 | $773/sf | +0.0% |
| Apr 24, 2020 | 4C | 2 BR · 2 BA · 950 sf | $710,000 | $747/sf | -3.9% |
| Jul 15, 2015 | 6B | 1 BR · 515 sf | $440,000 | $854/sf | -2.2% |
Market read. Most recent trades (2025) cleared a median $661/sf (floor-adjusted) across 1 sale. Floor-adjusted means each sale is restated to a constant mix of floors, so the figure can differ from the plain median of the sales listed above. Median listing discount 1.7% from the last ask — a recurring negotiation gap worth pricing into any offer or listing strategy.
The retrade record
Lines that have traded more than once in the public record — the building’s appreciation arc, apartment by apartment.
Full closing history with price-per-square-foot over time, the complete retrade record, and every line that has traded.
Sales sourced from NYC Department of Finance recorded transfers (BBL 3-02276-7501; 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.
What would your apartment rent for?
Enter your apartment and I'll send you what it would rent for, from comparable closed leases at Thornton Park and nearby.
Buying here? Condo closing costs with a mortgage typically run 3 to 6% of the price. See NYC co-op and condo closing costs, line by line.
Keep up with Thornton Park and its market
The Roebling Report, monthly: Manhattan sales data and analysis, including buildings like Thornton Park. Unsubscribe anytime.
We’ll use your email for The Roebling Report and note your interest in this building. See our privacy policy.
Comparable buildings
- 119 Lorimer Street — A nearby condominium with similarly limited residential scale and a tall, narrow form.
- 434 Marcy Avenue — A condominium from the same development period with a somewhat larger inventory.
- 441 Marcy Avenue — A mid-rise condominium offering a related purchase category in the same part of Brooklyn.
- 275 Manhattan Avenue — A similarly sized condominium in a lower-rise building farther north.
- 136 Powers Street — A lower-rise condominium from the same broad development era.
More Williamsburg buildings
- The Pad, 196–200 South 2nd Street — condominium
- The Umbrella Factory (710 Metropolitan Avenue) — 1930 condominium
- The Woodpoint, 128–130 Woodpoint Road — condominium
- Timberburg (179 North 10th Street) — condominium
- Two Northside Piers (2 Northside Piers) — 2009 condominium
- Warehouse 11 (214 North 11th Street) — 2009 condominium
The neighborhood
For the full neighborhood — its buildings, character, and market — read The Roebling Team Guide to Williamsburg.
How to read the facts on this page. Items attributed to an offering plan describe the building as it was offered at that filing — unit mix, square footage, the amenity program as planned. They are not a statement about how the building operates today. Tax and compliance figures are sourced separately to current City records and carry their own dates. House rules, staffing and fee policy can change by board resolution without any public filing: treat every policy line here as a starting point for diligence and confirm it with the managing agent. Where this page compares one building or neighborhood to another, that is our analysis of the recorded record — it names the measure, the period and the sample it rests on, and it is an observation about medians rather than a prediction about any particular apartment.
Considering a move at Thornton Park?
Request a private building brief with the relevant comparable sales, current and off-market availability, and an apartment-specific view of value.
646.939.7375 · c.cohen@compass.com