Which NYC building violations actually cost you money
A two-family in Bushwick comes back with fourteen violations. Three date to 1994. One is a cracked sidewalk slab. One says IN VIOLATION and shows $1,600 still owed. Your broker says every building on the block looks like this, and your broker is probably right. That still doesn't tell you which of the fourteen becomes yours.
The short answer: sidewalk first, then anything that blocks a sign-off
Roughly in order of how likely an open violation is to cost the next owner money:
DOT sidewalk violations aren't Buildings violations at all, which is why people misfile them. Under Admin Code 7-210 the owner abutting the sidewalk has to maintain it. They top this list for the enforcement path: 75 days to repair after a notice, then DOT can do the work and bill for it under 19-152. They're also the easiest defect to price, because the dataset carries the square footage. One carve-out, covering much of the housing stock this guide is about: 7-210 did not shift injury liability for owner-occupied one-, two- and three-family homes. The repair obligation still lands on them.
DOB safety violations are periodic-inspection failures: facade under Local Law 11/FISP, gas piping under LL152, elevators, parking structures, retaining walls. The obligation to file and repair recurs on a cycle, indefinitely. A facade cycle on a mid-rise is a capital number, not a fine.
DOB BIS violations, the general construction and structural stream, stay open until someone files a certificate of correction and DOB dismisses it. They don't age out. A twenty-year-old open one matters because it can sit between the building and a sign-off you need.
ECB violations look the scariest and are most often somebody else's bill. More below.
HPD housing maintenance violations are conditions a tenant lives with: heat, mold, pests, lead paint, plumbing, with Class C meaning immediately hazardous. Renting, this is the most decision-relevant record on the page. Buying, it says how the building has been run.
Why the city runs two violation systems at once
DOB's violation record is a records system: an inspector observes a condition, writes it against the premises, and the record stays until the condition is certified corrected. A filing cabinet with a state machine attached.
The ECB was never that. It's a tribunal, chartered separately under NYC Charter 1049-a to hear notices of violation and impose civil penalties: a summons, a respondent, a hearing, a decision. Local Law 35 of 2008 placed it inside OATH, which is why the hearing fields say OATH while the violation still says ECB.
So they aren't two flavors of one thing. One is the record of the condition, the other the docket of the case about it. A single cracked lintel produces a BIS violation (against the building) and an ECB summons (against a named respondent), living in different datasets with different keys, status vocabularies and lifespans.
Which answers "what follows the building." The condition does: an open BIS or safety violation waits for the next owner, because the obligation attaches to the premises. The penalty was assessed against whoever the summons named, and doesn't automatically re-bill to you at closing. That's why an eye-watering ECB total is frequently noise, and why unpaid city penalties are what a title search exists to surface. Any number big enough to matter belongs with your title people.
The two fields that tell you whether anyone actually paid
An ECB record carries two money figures, and only one of them is a live number. The penalty imposed is what the tribunal assessed. The balance due is what is still owed. A five-figure penalty against a zero balance was litigated and paid years ago, and a report that shows you the first without the second is telling you about somebody's bad month in 2014.
Two things make that history hard to assemble, and both are why a report beats a search box. The lot number is stored as text with inconsistent padding inside a single record set: in the ECB data it is four characters on 1,478,541 rows and five on 320,221, and the DOB violation record skews the other way, five characters on 2,444,890 rows and four on 18,159 legacy rows issued between 1968 and 2012, of which 1,566 are still open. Some lots exist only in the legacy form. Nosy Neighbor searches every width, so a legacy-only lot shows its violations rather than a confident blank.
Status is the other half, and every agency spells "open" differently: ECB resolves to RESOLVE when paid or dismissed, and DEFAULT specifically means nobody turned up to the hearing; DOB's general violations use a category prefix; DOB safety violations are simply Active; HPD marks the subset serious enough to legally suspend rent; DOT sidewalk violations carry no status at all and are open until a dismissal date appears. Nosy Neighbor normalizes all five into one open/closed column, which is most of the work in reading a violation history.
Why the raw count is the wrong number
Every article in this genre says to look for "a pattern of violations" and never defines a pattern, because a raw count is meaningless on its own. A 60-unit prewar rental generates HPD violations at a rate a two-family structurally cannot, and a renovated building generates DOB rows precisely because someone pulled permits and did the work properly. Compare per unit, against buildings of the same era and size, and read the dates: fourteen violations across thirty years is a different building from fourteen in the last eighteen months.
What to check, in order
Open sidewalk violations first: cheapest to price, most likely to become yours. Then active DOB safety violations, the largest number if the building runs a facade or gas cycle. Then open BIS violations, asking of each whether it sits in front of a sign-off you'd need. Then ECB balance due, not penalty imposed. Read HPD Class C last if you're buying and first if you're renting.
Look up any NYC address to see all five streams on one page, already normalized.
These feeds move daily, and the ranking above is the order that matters: what attaches to the premises first, what was somebody else's bill last.