170 Grafton Street, Brooklyn
Two-family · built c. 1930 · Block 3551, Lot 131.
Building permits
- Major Renovation — Enlargement, filed Nov 17, 2025, estimated cost $490K, 8 units added, 3 stories, described as “Combing tax lot 21 & 131 into 1 single zoning lot, to remain 2 separate tax lots; interior renovation to increase number of dwelling units from 2 to 10 units, to an existing 3 story residential building.”
Property taxes
- Assessment
- $49,260
- 2026–27 tax
- $2,883
- Market value (city estimate)
- $821,000
- Taxable value
- $14,530
- Assessed land
- $20,220
- Assessed improvements
- $29,040
Zoning
R6: floor area ratio 1.13 built, 2.43 allowed by base zoning.
Flood zone
Current FEMA flood map: zone X, minimal flood hazard.
Recent sales
- Jan 27, 2026: $840,000, 2,272 sq ft ($370 per sq ft)
- Sep 18, 2025: $610,000
- Jun 30, 2023: $754,300
Open-market sales since 2016, from the Department of Finance’s sales files.