Code: Alteration (DOB project type)
Description: (Building alteration) is the DOB term for construction work that changes an existing building, such as layouts, rooms, or systems, without demolishing the whole structure. Many projects that owners call a “renovation” in everyday language are filed with the NYC Department of Buildings as “alterations.
Practical Meaning: For a NYC homeowner, an alteration is the official DOB category for most non‑demolition projects, including new kitchens, bathrooms, basement build‑outs, layout changes, and many “renovations.” If your scope goes beyond simple cosmetic work like painting or basic flooring, you should assume DOB may treat it as an alteration that needs plans, permits, and approvals.
Where You May See It: You may see “alteration” and labels like “Alt 1” or “Alt 2” on DOB job filings, plan sets from your architect, BIS or DOB NOW job records, co‑op or condo alteration agreements, and contractor proposals for larger projects.
Why It Matters: Knowing that DOB uses “alteration” instead of “renovation” helps you match your project to the correct permit type and avoid work‑without‑permit violations, fines, or orders to legalize or undo the work later. It also matters for future sales and refinancing, because buyers, lenders, and building managers often check whether major alterations were properly filed, approved, and signed off by DOB