Code: Class B - Building (Building use category)
Description: (Class B Multiple Dwelling Building Type) is a legal building category on the Certificate Of Occupancy for buildings used mainly for transient or rooming‑house type occupancy, such as SROs, rooming houses, or hotels. It is not an HPD violation class and does not by itself mean there is any open hazardous condition in the building.
Practical Meaning: For a NYC homeowner, this means the building is legally treated as a Class B multiple dwelling for mostly temporary or rooming‑type stays, not as a standard permanent Class A apartment building. You must follow special rules for SRO or transient use, including stricter safety, egress, and occupancy rules, and you cannot assume Class A leasing and tenant‑protection rules apply in the same way.
Where You May See It: Certificate Of Occupancy (CO), DOB NOW, DOB BIS, title report, zoning or land use studies, bank or lender underwriting documents, short‑term rental compliance letters.
Why It Matters: It affects what type of tenants and stays are legally allowed, which fire and detector rules apply, whether short‑term rentals can ever be legal, and how strictly the city can enforce against illegal occupancy. Do not confuse this with a Class B HPD violation, which is about a specific hazardous condition that needs repair, not the overall building use category.