638 HUMBOLDT STREET
638 HUMBOLDT STREET is a Class C2 (walk-up, five to six) building in Brooklyn (BBL 3026860059) built in 1931, with 6 residential units across 3 floors.
The building is in NYC community district 301, council district 33, zoning district R6B, on a 2,450-square-foot lot with a building footprint of 4,190 square feet.
The current registered owner of record per NYC PLUTO is KOSTRZEWSKI REVOCABLE TRUST.
The most recent ACRIS deed transfer for this BBL was recorded on February 5, 2026 when Sylvia Druzynski; The Kostrzewski Revocable Trust conveyed the property to 638 Humboldt Street Llc for $560K. The transaction was recorded as cash (no paired mortgage instrument).
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
- Head OfficerSYLVIA DRUZYNSKI
- Corporate OwnerKOSTRZEWSKI REVOCABLE TRUST
Most recent deed
Recent ACRIS documents (last 1)
Building stats
- Zoning:
- R6B
- Lot size:
- 2,450 sqft
- Building area:
- 4,190 sqft
- Floors:
- 3
- Assessed value:
- $757K
- Community district:
- 301
- Council district:
- 33
HPD violations
Recent HPD violation details
- Class AInspected May 5, 2026(A) § HMC:FILE ANNUAL BEDBUG REPORT IN ACCORDANCE WITH HPD RULE AS DESCRIBED ON THE BACK OF THIS NOTICE OF VIOLATION OR AS DESCRIBED ON HPD…
- Class CInspected Apr 16, 2026§ 27-2005, 27-2007, 27-2041.1 HMC, §238, § 309; § 107 (2) ( C) MDL AND 28 RCNY §25-171: REPLACE OR REPAIR THE SELF-CLOSING DOORS THAT IS MIS…
- Class CInspected Dec 26, 2025§ 27-2005, 2007 ADM CODE REMOVE DEVICE PREVENTING DOOR FROM BEING SELF-CLOSING HOOK AND EYE INSTALLED AT BUILDING ENTRANCE DOOR , 1st STORY
- Class CInspected Dec 26, 2025§ 27-2044, 2041.1 HMC: §238 MDL and 28 RCNY §25-171: REPLACE OR REPAIR THE SELF-CLOSING THE DOORS THAT IS MISSING OR DEFECTIVE HINGES AT DOO…
- Class BInspected Dec 26, 2025§ 27-2045(B)(1)(A) HMC, § 12-01, § 12-03 RCNY REPAIR, REPLACE OR PROVIDE AN APPROVED AND OPERATIONAL SMOKE DETECTING DEVICE, INSTALLED IN AC…
Recent ACRIS activity
Frequently asked questions about 638 HUMBOLDT STREET
Who owns 638 HUMBOLDT STREET?
The current registered owner of record for 638 HUMBOLDT STREET per NYC PLUTO is KOSTRZEWSKI REVOCABLE TRUST. The most recent ACRIS deed transfer for this BBL was recorded on February 5, 2026 when the property was conveyed to 638 Humboldt Street Llc. PLUTO ownership is refreshed monthly by NYC Department of Finance; the registered owner may not reflect transactions recorded within the last 30 days.
When was 638 HUMBOLDT STREET last sold?
The most recent ACRIS deed transfer for 638 HUMBOLDT STREET was recorded on February 5, 2026, when Sylvia Druzynski; The Kostrzewski Revocable Trust conveyed the property to 638 Humboldt Street Llc for $560K. The transaction was recorded as cash (no paired mortgage instrument).
How many HPD violations does 638 HUMBOLDT STREET have?
No open HPD housing-maintenance code violations are on record for 638 HUMBOLDT 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 is the assessed value of 638 HUMBOLDT STREET?
NYC Department of Finance assesses 638 HUMBOLDT STREET at $757K for the current tax year. NYC assesses property at a fraction of estimated market value (the assessment ratio varies by tax class — 6% for tax class 1 one-to-three-family dwellings, approximately 45% for tax class 2 rental apartment buildings), so the market value implied by this assessment is meaningfully higher. Assessment data is published by NYC Department of Finance.
What building class is 638 HUMBOLDT STREET and what does that mean?
638 HUMBOLDT STREET is NYC building class C2 — Walk-up, five to six. A 3-to-6-story walk-up apartment building, 5-6 residential units. 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.