# 550 Union Street, Brooklyn

Industrial · built c. 1910 · Block 440, Lot 29.

On Umarelli: https://umarelli.org/nyc/3004400029/550-union-street

More construction in Gowanus: https://umarelli.org/nyc/brooklyn/gowanus.md

## Building permits

- Alteration, filed Sep 3, 2026, estimated cost $1K, described as “Installation of temporary heavy duty sidewalk shed as per plans. No change in use, egress or occupancy. Sidewalk shed shall comply with chapter #33 of 2022 the NYC building code. Live load 300PSF.”
- Alteration, filed Mar 11, 2026, described as “Construction fence”
- Major Renovation — Conversion, filed Oct 1, 2025, estimated cost $3.3M, 8 units added, 5 stories, described as “Alteration CO application as-of-right conversion of existing 2 story commercial building into a residential R-2 building with horizontal & vertical enlargement for 8 D.U.'s, 5 stories & Cellar. New egress stairs & building to be fully…”

## Property taxes

- Assessment: $248,850
- 2026–27 tax: $24,223
- Market value (city estimate): $553,000
- Taxable value: $223,290
- Assessed land: $32,400
- Assessed improvements: $216,450

## Zoning

M1-4/R6A: floor area ratio 1.26 built, 3.00 allowed by base zoning.

## Recent sales

- Jun 27, 2025: $4,000,000
- Feb 28, 2024: $4,000,000
- Jul 27, 2021: $2,000,000

Open-market sales since 2016, from the Department of Finance’s sales files.

## Flood zone

Current FEMA flood map: zone X, minimal flood hazard.

## Board and land use applications

- Gowanus Neighborhood Plan (City Planning 2018K0382): Zoning map change, Zoning text change, City map change, Urban development action area, Completed, decided Dec 6, 2021. The Gowanus Neighborhood Plan is a shared, long-term vision for a thriving neighborhood. It looks to identify strategies for an equitable, resilient and sustainable Gowanus, with more local jobs and housing. The Plan supports community…

## In the news

[Demolition Progresses For New Residential Building At 544-550 Union Street in Gowanus, Brooklyn](https://newyorkyimby.com/2026/07/demolition-progresses-for-new-residential-building-at-544-550-union-street-in-gowanus-brooklyn.html), New York YIMBY, Jul 27, 2026.

From New York City and Jersey City public records, refreshed within a day of each release. Sources: https://umarelli.org/sources. Methodology and corrections: https://umarelli.org/methodology