21 DIAMOND STREET
21 DIAMOND STREET is a Class C3 (walk-up, pre-1929) building in Brooklyn (BBL 3026840028) built in 1931, with 4 residential units.
The current registered owner of record per NYC PLUTO is KELLY MARTIN III.
MetroDeeds shows no confirmed ACRIS deed transfer for this BBL in the last 5 years of recorded NYC public-records data.
The building is registered with NYC HPD's landlord-registration system and has no open HPD housing-maintenance code violations on record as of May 18, 2026.
Data sourced daily from NYC PLUTO (Department of City Planning), NYC ACRIS (Department of Finance), and NYC HPD housing-maintenance code violations.
Owner of record
HPD registered contacts
- Site ManagerMARTIN KELLY
Most recent deed
Building stats
HPD violations
Recent HPD violation details
Frequently asked questions about 21 DIAMOND STREET
Who owns 21 DIAMOND STREET?
The current registered owner of record for 21 DIAMOND STREET per NYC PLUTO is KELLY MARTIN III. MetroDeeds shows no confirmed ACRIS deed transfer for this BBL in the last 5 years of recorded NYC public-records data.
When was 21 DIAMOND STREET last sold?
MetroDeeds shows no confirmed ACRIS deed transfer for 21 DIAMOND STREET in the last 5 years of recorded NYC public-records data. NYC ACRIS coverage extends back to 1966; an absence in our 5-year window typically means either the BBL has not transacted recently, or the most recent recorded document is not a DEED type (such as a refinance rather than a sale).
How many HPD violations does 21 DIAMOND STREET have?
No open HPD housing-maintenance code violations are on record for 21 DIAMOND STREET as of May 18, 2026. The building is registered with NYC HPD's landlord-registration system. HPD violation data is pulled daily from the NYC Open Data violations feed.
What building class is 21 DIAMOND STREET and what does that mean?
21 DIAMOND STREET is NYC building class C3 — Walk-up, pre-1929. A walk-up apartment building constructed before 1929, typically 3-6 stories and often rent-stabilized. Building class is assigned by NYC Department of Finance and recorded in PLUTO; it determines the property's tax class and the regulatory regime that applies.