Ask a Brooklyn managing agent how many people can get into their building and the honest answer is usually a pause. Not because the building is careless, but because it has had three lives: the freight door is there because it was a warehouse, the second street entrance is there because it was two businesses, the restaurant downstairs has its own staff door and its own hours, a tenant moved out in 2023 and nobody is certain the fobs came back, and the super covers two other buildings on the block. Security in a Brooklyn building starts with the list of who legitimately holds access — and then with somebody actually standing in it. Dahlcore Security Guard Services supplies building officers across Brooklyn for converted lofts and warehouses, factory and industrial conversions, brownstone and row-house portfolios, co-ops and condominiums, and new mid-rises over ground-floor retail: desk and vestibule posts, evening and overnight rounds, and a written record management reads the next morning. Whatever buzzers, cameras, readers and intercoms your building already owns, the officer runs them and we supply none of them: Dahlcore does not install, sell, service or resell systems. Posts are unarmed by default. The company is a licensed New York security guard agency, veteran-owned, founded in 2018, and led by Ian Dahlberg, who brings more than 23 years of security experience. Brooklyn is served from our Staten Island headquarters and our Manhattan office at 250 Park Avenue.
Who Else Has a Key to Your Brooklyn Building
Not a list of doors — a list of people who can legitimately open one. In a converted Brooklyn building it is nearly always longer than the owner expects, and an officer’s first week is mostly learning it. The list belongs to the building; we work from it, and we tell you when what we see on the door does not match it.
The building that used to be something else
A purpose-built residential block has one front door because somebody drew it that way. A great deal of Brooklyn does not. The loft in Gowanus has a roll-down freight door on the street because trucks used to back into it. The apartments in Greenpoint have two entrances because the ground floor was two shops. The brownstone in Bed-Stuy has a garden-level door, a stoop door and a hatch to the areaway, all of which were once one household’s business and are now four tenancies’ business. The building in Sunset Park has a yard and a curb cut nobody uses for anything except storing a skip. None of this is a defect; it is what conversion leaves behind, and it is why a security plan copied from another building fails here. What an officer needs is not a generic post order but an accurate one: which of your doors are live and when, which are alarmed and which only look it, which tenancy each belongs to, who is supposed to come through it, and what happens when somebody comes through one that was meant to be shut. We work that out on the walkthrough, with the person who actually runs the building, before anybody is posted.
Four Brooklyn Buildings and What They Used to Be
Named by their former life rather than their current listing, because the former life is what the officer has to work around.
The warehouse that is now offices
Gowanus, Sunset Park, Bushwick, Red Hook and the Navy Yard fringe: heavy floors, a freight door, a goods lift, one stair, and eight or ten small businesses that each thought they were renting a quiet floor. The security problem is that the building was designed to admit pallets rather than people, so the obvious entrance is the one nobody staffs. A desk or vestibule post at the door the tenants actually use, plus a round that includes the freight side, the roof hatch and the yard, turns a loading building back into an occupied one.
The factory that is now apartments
Greenpoint, Williamsburg, Bushwick and the Gowanus edge: large floor plates cut into units, long internal corridors, a service stair the residents never use, a roof that used to carry plant, and often a ground floor still let commercially. Residents are used to the building being informal and will hold a door for anyone carrying a box. The post is deliberately sociable — an officer residents know by name, at the hour the building is least itself, covering the corridors and the roof door on a round rather than watching a screen.
The row of brownstones cut into units
Bed-Stuy, Crown Heights, Clinton Hill, Park Slope, Carroll Gardens and Prospect Heights: a stoop door, a garden-level door, an areaway, a rear yard reached through a neighbour’s, a shared party wall, and an owner with several of them within a few blocks. There is no lobby to stand in, so the post is a round: a route through each building on the interval the owner sets, verified by GPS and geofence, with a log per building that the owner reads in the morning and that turns four vague complaints into one clear pattern.
The new mid-rise over a restaurant
Downtown Brooklyn, Fort Greene, Boerum Hill, Cobble Hill, Brooklyn Heights, Bay Ridge and Flatbush: a proper residential lobby, a package room, an amenity floor — and a commercial base whose deliveries, refuse, staff and customers all touch the building at hours the residents are asleep. The post order’s real work is the boundary: which door belongs to the restaurant, when it is live, who the officer calls on the commercial side at midnight, and what happens when the two populations meet in the one corridor they share.
What the Officer Decides, and What the Officer Calls About
The single most useful page of a Brooklyn post order is this one, because a building with several tenancies produces judgement calls all night. Both columns are written with you before the first shift, so nobody is improvising at two in the morning — and so nobody is phoning you about something they were supposed to handle.
Decided at the post
- A resident or tenant the officer recognises arriving late, with guests, with a delivery — greeted and through
- A visitor on the list — confirmed against the building’s own procedure and sent up
- A courier — handled the way the building has agreed packages are handled, and logged
- A door found open on the round — closed if closing it is safe and simple, and recorded with the time
- Somebody in the vestibule sheltering — spoken to first, moved on without force, logged either way
- Noise, a gathering, a blocked stair — asked, de-escalated, written down
Called in, not decided
- Anything involving injury, fire, a weapon or a crime — 911 first, then the agent, always
- A person who refuses to leave — the officer holds position and calls; nobody is removed by force
- A contractor with no booking — turned away or held at the door while the agent is called
- A credential that should not have worked — logged and escalated the same night, deactivated by you
- Anything a resident says about another resident, or about occupancy — recorded and passed on, never acted on
- A fault in a door, alarm, light or lift — reported to the super and the agent, never touched
When your quietest hour is a tenant’s busiest
Brooklyn puts food and drink under apartments more than any other borough, and it creates a specific problem that has nothing to do with anyone behaving badly. At eleven at night the residential half of the building is asleep and the commercial half is at its peak: a delivery at the side door, refuse going out, staff leaving in ones and twos, customers on the pavement, a propped door because somebody is carrying crates. The officer is standing in both buildings at once. What makes that workable is not vigilance, it is agreement — reached at the walkthrough with the managing agent and, where they will come, the commercial tenant. Which door is the restaurant’s and until what hour. Whether staff use it after close and who they are. Where refuse goes and when. What the officer does about a propped door: close it, or find the person and ask. Who is called on the commercial side at midnight, because it will not be the residential agent. Written down, this is an ordinary shift. Left unwritten, it is the thing residents complain about for a year and the reason a post gets blamed for a building’s design.
Brooklyn Building Security FAQ
Answers for Brooklyn owners, co-op and condo boards, and the agents who run their buildings. The general questions — what a building post costs you in disruption, when a doorman is the better answer, whether a building needs an FLSD, and how an engagement is planned from first call to first shift — are all on the main Building Security page. For credentials, readers and coworking floors, see Access Control in Brooklyn; for anything with a guest list, Event Security in Brooklyn.
We have never audited who holds a key or a fob. Is that something your officer does?
Not the audit itself, and it matters that you know that. Issuing, collecting, rekeying and deactivating credentials is the owner’s, the agent’s or the board’s work, in the system the building owns — an officer who started cutting keys or editing your access list would be doing a job we are not there to do. What the officer gives you is the other half of it: a nightly record of who actually came through which door, which is usually the first time an owner can compare the list they think they have against the building they actually have. Most key audits we have seen in Brooklyn started with somebody reading three weeks of that log.
Our ground-floor restaurant’s staff use the same side door as the residents. Can that be separated?
Physically, only by your architect — a second door, a changed lock line or a partition is construction, not security. Operationally, yes, and it is largely a matter of writing it down. The post order names the hours that door is commercial and the hours it is residential, who on the restaurant’s side the officer can call, what happens when it is propped during a delivery, and whether staff leaving after close go out that way or the front. Where the commercial tenant will sit in on the walkthrough, that conversation takes twenty minutes and saves a year of complaints.
A tenant moved out two years ago and we are fairly sure they still have a fob. What now?
You deactivate it — in your system, today, and it costs nothing to do. An officer cannot do that for you and would not have the access to. What the officer does is make the gap visible while it exists: someone entering with a credential the building does not expect is logged the same night and escalated to you rather than noted in passing, and the record says which door, what time and how often. In a converted building with several changes of tenancy, that is frequently how an owner finds out how many credentials are still live.
Our building has three street doors because it used to be three businesses. Do we need three officers?
Almost never. The usual answer is one post at the door the building actually uses, with the others either taken out of service by the owner or covered on a round — and the post order says which is which and at what hours. Three staffed doors is a proposal we would only make if all three are genuinely live at the same time with different populations, and we will tell you when that is not the case. Recommending posts you do not need is the fastest way to lose a building, and we would rather keep it.
Deliveries pile up in our vestibule all day and things go missing. Does an officer fix that?
An officer changes it by being there, which is most of it — packages left where somebody is standing tend to stay there, and the ones that do go missing stop being a mystery because there is a log and, where the building has cameras, a time to look at. What the officer will and will not do is worth agreeing up front: whether they sign for anything (many buildings prefer not, and we follow the building), where parcels are moved to, whether residents are notified and how. What an officer does not do is investigate a theft. That is a police matter and, if you want it pursued, a police report — we document, we do not investigate.
Our co-op board would like the officer to take out the recycling and change bulbs on quiet nights. Is that allowed?
No, and boards ask us this often enough that it is worth answering plainly rather than politely. A security officer on post is there to watch a building and the people in it; the moment they are in the bin area with a bag or up a ladder with a bulb, they are not watching anything, and they are doing work that belongs to your porter or your super under different terms and different insurance. It also changes how residents read the officer, which quietly costs you the thing you hired for. What an officer will always do is tell you the bulb is out, the recycling was not collected and the bin-room door is ajar — in writing, the same night.
Our cameras were put in by the previous owner and nobody has the login. Can you sort that out?
No — and anyone who says yes is selling you something. We do not install, service, reconfigure or resell camera, access or alarm systems, and we have no business inside your recorder. You will need the installer or a licensed integrator for that. What our officer does is work with whatever you do have access to, and cover with presence what the cameras currently are not covering. It is worth saying that this is common and not embarrassing: plenty of Brooklyn conversions have a system that came with the building and a password that left with somebody.
Our building is four storeys with no lift and no lobby. Is a building officer overkill?
Sometimes, and we will say so at the walkthrough rather than after you have signed something. A single small building often does not justify a standing post; what it justifies is either an evening presence at the hours that are actually difficult, or a place on a round covering several of your buildings if you own more than one nearby — which is how most of our Brooklyn brownstone and row-house work is structured. If the honest answer is that better lighting and a door that latches would do more than an officer, that is the answer you will get.
Where in Brooklyn the building posts are
The converted lofts and warehouses of Gowanus, Sunset Park, Bushwick, Red Hook and DUMBO; the factory conversions of Greenpoint and Williamsburg; the brownstone and row-house portfolios of Bed-Stuy, Crown Heights, Clinton Hill, Prospect Heights, Park Slope and Carroll Gardens; and the new mid-rises over ground-floor retail in Downtown Brooklyn, Fort Greene, Boerum Hill, Cobble Hill, Brooklyn Heights, Bay Ridge and Flatbush. At each of them the walkthrough is done with the person who actually runs the building, the post order and the call list are written with you, the round is verified by GPS and geofence, and the named account manager who keeps it works from our Staten Island headquarters or 250 Park Avenue — there is no Brooklyn office, and we would rather say so than imply one.
What Clients Say About Dahlcore Officers
Explore real feedback from clients and from the public on how officers behave in front of the people who use a building every day.
“I only use Dahlcore for my security services. Every other security agency I have had problems with their staff. Their staff are properly trained and respectful.”
“Makes me feel safe and that’s the point! Professional and friendly service.”
“Ian is great to work with and has a good team. This security company is who you should hire for your next project.”
Start With the List of Who Can Get Into Your Building
Tell us the building, what it used to be, how many doors it has, who holds a key, and what has been happening in the evenings. A supervisor walks it with your super or agent, the post order and the call list are written with you, and you approve the recommendation before the first shift — including if the recommendation is a smaller one than you expected. Consultations are free.
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