Our thoughts are with Flatbush

Everyone at SRE is thinking of the eight people who died, among them two children and two construction workers, of the 18 people who were injured, and of the families who lost their homes on Flatbush Avenue. We are grateful to the more than 250 firefighters and emergency workers who searched the site for 24 hours, and to the construction workers who helped dig their neighbors out of the rubble.

The investigation is still under way, and questions of responsibility belong to the City, the District Attorney and the courts. This article sets out what the public record shows so far and the safeguards New York requires when construction happens next to an occupied building, because thousands of New Yorkers live beside an active site every day.

What happened on Flatbush Avenue

Shortly after 4 p.m. on November 11, the rear of 1321 Flatbush Avenue, a four-unit apartment building with a ground-floor store dating to about 1930, collapsed into the excavation at 2625 Bedford Avenue next door, where crews had been digging earlier that day. The FDNY ended its search on the afternoon of November 12, and three neighboring buildings at 1323, 1325 and 1327 Flatbush Avenue remain under vacate orders.

The lot next door held permits for excavation to 14 feet below grade and for a three-story building. After the collapse, DOB issued a full stop-work order citing unsafe construction operations, and the Brooklyn District Attorney’s office joined the investigation. The City has also begun inspecting about 100 other sites connected to the five companies involved in the project.

What the record shows so far

Public filings show warning signs that built up over the eight months before the collapse (Exhibit 1).

• March 5. A pre-construction survey of 1321 Flatbush documented visible cracking and rated the facade facing the site in poor condition. The survey noted that details of the building’s foundation were not provided.

• March 20. DOB stopped demolition on the lot because required overhead protection for neighbors, such as netting and sidewalk sheds, was missing.

• April 23. Inspectors found the one-story building on the lot had been demolished despite the order and issued a further violation.

• May 8. DOB lifted the stop-work order after the conditions were corrected.

• June 10. The owner notified neighbors that excavation would begin within 30 days.

The engineering records also show that the risk to the building next door was identified before any digging began. The project’s geotechnical report, as reported by ENR, said buildings along the property line would need underpinning and warned that excavation and vibration could damage them. The approved support-of-excavation plan called for steel soldier piles with timber lagging set in lifts of no more than two feet, rakers and tangent piles, with baseline readings before excavation and optical surveys at least weekly after it. The plan also set clear triggers: notify at a quarter inch of movement, and stop work at half an inch or when a crack gauge opened more than 2 millimeters (Exhibit 2).

As of November 12, DOB’s records listed the required special inspection of sheeting, shoring and bracing as identified but not yet certified. That status alone does not show that inspections were skipped, and investigators have not said whether 1321 Flatbush was underpinned or what the monitoring instruments recorded.

What engineers are saying

Engineers interviewed this week largely describe the same mechanism, while cautioning that the cause has not been established. Stanford’s Gregory Deierlein told Scientific American that soil beside an occupied building carries pressure from that building, so the excavation support has to be stiff enough to keep it from moving, and that the age and condition of the collapsed building may have played a secondary role. Joe DiPompeo of Structural Workshop told Construction Dive that excavation support was visible at the site and that a failure of the soil bracing would produce a collapse much like this one. Northeastern University’s Mehrdad Sasani said photographs suggest the excavation may have gone deep beside the building without adequately supporting the soil beneath it. Construction attorney Timothy Hegarty of Zetlin & De Chiara added that the margin for error is very small when new work sits beside century-old buildings.

Read together, these views describe a system in which the design, the field installation and the monitoring all have to hold at the same time. An old masonry building with shallow foundations has little capacity to absorb movement, so a lapse in any one of the three can reach the building next door within hours.

How does the Building Code protect the building next door?

The Building Code makes whoever is doing the work responsible for protecting adjoining buildings and the people in them. Chapter 33 of the code, and Section 3309 in particular, turns that duty into specific steps that start before any work begins.

The steps run in order, from notice to neighbors 60 days before work through daily monitoring while the excavation is open (Exhibit 3).

Where projects get into trouble

Most failures near occupied buildings trace back to a gap between the approved plan and what happens in the field. A crew removes bracing early to make room, an excavation goes deeper than the drawings allow, or monitoring readings are taken and no one acts on them. Each of these is a decision made on a single day, and each is easy to miss without someone on site whose job is to check.

The Flatbush record so far fits that pattern. The drawings anticipated the risk to the building next door, so the questions investigators face concern what was installed, what was measured and who acted on the readings.

Older buildings raise the stakes. Much of Brooklyn’s housing stock is unreinforced masonry with shallow foundations and shared party walls, so work on one lot can load or undermine the building beside it. When a pre-construction survey already records cracking, as it did at 1321 Flatbush, the monitoring thresholds become the building’s main line of defense.

What happens to the buildings next to a collapse?

When a building falls, the buildings beside it lose part of their support and part of their protection from the weather at the same moment. On Flatbush Avenue, the City placed vacate orders on 1323, 1325 and 1327 Flatbush Avenue while engineers assess them. Their condition has not been made public, but in collapses like this one, getting neighbors home safely tends to follow the same sequence (Exhibit 4).

1. Make the site safe. Engineers brace the exposed wall and any floors that bear on it before debris is removed, and debris removal is sequenced so that it does not take away support the neighboring building still depends on. Survey points and crack gauges go on the neighboring buildings right away, so any further movement is caught early.

2. Close the building to the weather. A wall that was once interior is now outside. Under Section 3309.9 of the Building Code, the weatherproof integrity of an exposed adjoining wall has to be maintained, and with winter approaching, temporary weather protection keeps water and freezing from damaging the masonry further while the investigation continues.

3. Assess the structure. An engineer inspects the exposed party wall, checks that the floor joists bearing on it are still anchored, looks for undermined footings, and decides whether the foundation needs underpinning. Under the Administrative Code, repair and maintenance of a party wall is the joint responsibility of the owners on both sides of it, so this assessment also sets out who must do what.

4. Repair permanently. Typical work includes rebuilding or repointing damaged masonry, anchoring joists, underpinning where the soil was disturbed, and finishing the exposed face as a permanent, fire-rated and waterproofed exterior wall. Most of this work needs DOB permits and inspections.

5. Lift the vacate order. Once the conditions are corrected, the owner asks each agency that issued a vacate order to inspect and rescind it. Residents can return only when every one of those orders has been lifted.

Each step depends on clear records: what the wall looked like before, what moved and when, and what was repaired. The same discipline that protects a building during excavation also shortens the time it takes to bring residents home after damage.

What should owners do before building next to an occupied building?

Owners carry legal and moral responsibility for the work they commission. Four steps reduce the risk to neighbors and to the project.

1. Survey and assess before you dig. Commission the pre-construction survey and engineering assessment early, confirm the neighbor’s foundation conditions, and share the results with the adjoining owners so everyone starts from the same record.

2. Make monitoring someone’s job. Set movement thresholds, assign a person to read the instruments, and agree in advance on who stops work when a threshold is crossed.

3. Treat enforcement history as an early warning. A stop-work order during demolition says something about how a team will run the excavation that follows. Before the next phase starts, find out why it happened and change how the work is supervised.

4. Keep independent eyes on the field. An owner’s representative or construction manager checks that the work matches the approved drawings, that required special inspections are performed and certified as each stage is built, and that stop-work orders and DOB violations are fully resolved before work moves forward.

Own a building next to an excavation? What you can ask for

Most of the Building Code’s protections are owed to the owners and residents next door, and they work best when those owners use them. If a lot beside your building is about to be excavated or demolished, four steps put you on firm footing.

1. Read the notice and the survey. The developer must notify you before work begins and, where the excavation is close or deep, survey your building’s condition. Ask for a copy of the pre-construction survey, check that it describes your building accurately, and take your own dated photographs of every existing crack.

2. Ask what protects your building. Ask whether the support-of-excavation plan calls for underpinning or bracing on your side of the lot line, and what movement and vibration levels will stop the work.

3. Ask to see the monitoring data. Movement, crack and vibration readings are taken to protect your building, so it is reasonable to ask how often you will receive them and whom to call when a reading moves.

4. Bring your own engineer. Many adjoining owners hire an independent engineer or owner’s representative to review the protection plan and monitoring on their behalf. The cost is often addressed in the access agreement with the developer.

If you see new cracking, doors or windows that suddenly stick, or water entering through a shared wall, document it and report it to the developer and to DOB through 311. If the condition looks immediately dangerous, leave the building and call 911.

How SRE protects the building next door

Flatbush shows how much depends on the daily work between the approved drawings and the excavation. That daily work is what SRE Engineering does. Our resident engineers and inspectors oversee construction for NYC agencies such as DEP and DDC, where independent inspection, documented verification and the authority to stop unsafe work are written into every contract. We bring that same discipline to private developers and building owners, with particular care for the occupied buildings beside their sites.

When a project excavates, underpins or demolishes next to an existing building, SRE’s oversight covers five areas:

1. We make sure adjacent buildings are surveyed, photographed and recorded before work begins, including their foundation conditions, so every finding feeds the protection and monitoring plan.

2. Our engineers check support of excavation, underpinning and demolition against the approved drawings and permits at each stage. Work pauses at defined hold points until the engineer of record confirms the next step, and we track every required special inspection through to certification.

3. We review crack gauges, survey points and vibration readings against the notification and stop-work thresholds in the approved plan, and we act the same day a reading moves.

4. When a condition looks unsafe, a neighbor reports new cracking or a stop-work order is posted, we alert the owner, the engineer of record and, where required, DOB. We then confirm on site that work stays stopped until the condition is corrected.

5. Daily reports, photos and inspection logs show the owner, DOB and the neighbors what was checked, when and by whom.

We also work on the other side of the lot line. For owners of buildings next to an excavation, we review the protection plan and monitoring data on their behalf. For owners repairing a building after damage from adjacent work, we manage the stabilization, the permanent repairs and the inspections that lead to re-occupancy.

Whether you are planning excavation beside an existing building or you own the building next door, bring us in before work begins, while protection can still be designed into the job. Learn more about our services or contact us to talk through your site.

This article summarizes public requirements and reporting as of November 13, 2026, for planning purposes, and is not legal or engineering advice. If you see an immediately hazardous condition at a construction site, call 911.

Sources (opened Nov. 13, 2026)

• ENR: Eight Dead, 18 Injured in Brooklyn Building Collapse Next to Construction Site

• Construction Dive: Construction site next to fatal Brooklyn collapse previously violated stop-work order: DOB

• Scientific American: Why did a Brooklyn building collapse so suddenly? Experts weigh in

• Northeastern Global News: Brooklyn building collapse raises questions about neighboring construction (Nov. 12, 2026)

• Gothamist: FDNY ends search at Brooklyn building collapse

• Gothamist: Developer at Brooklyn collapse site had record of flouting orders from city agency

• ABC News: 8 dead, including 2 children, after building collapses in Brooklyn

• CBS New York: Flatbush building that collapsed had 98 open violations, city records show

• The Real Deal: Collapsed Flatbush building, adjacent job site have history of violations

• NYC DOB: Vacate Order FAQs

• NYC Administrative Code, Article 306: Party Walls

• NYC DOB: Construction safety code requirements, case studies (2019)

• NYC DOB: Lot Line Code Requirements: Excavations, Underpinning, Foundations and Protection of Adjoining Properties (Build Safe Live Safe 2023)

• NYC DOB: Construction Advisory 2024-004, Excavation Safety: Safeguards and Reminders

• NYC DOB: 2022 Building Code, Chapter 33, Safeguards During Construction or Demolition