These are the questions Brooklyn owners, tenants and shopkeepers bring to us before a smart lock goes on, grouped by the part of the house they are about: the stoop doors, historic fronts and older wood, the shared house, deliveries, newer towers and the avenues. Booking, coverage and day-of-visit questions are in the FAQ near the end of the page. None of this is legal advice; where a law or a city rule is relevant we name it so you can read it yourself.
The stoop, the vestibule and the garden door
On a brownstone with double front doors and a vestibule, which door should get the smart lock — the outer pair or the inner door?
Usually the inner door for everyday use, and the outer pair for security and deliveries — but it depends on how the house is used. The inner door is sheltered from rain and sun, it is a single leaf that closes against one frame, and it is the door the household actually opens dozens of times a day. A keypad or fingerprint lock there lasts longer and behaves better than one exposed at the top of the stoop. The outer doors are heavier, often original and harder to fit, and in many houses they stay latched in the day and are deadlocked at night.
Brooklyn owners argue about this constantly. One thread on Brownstoner's forum, started in 2024, asks exactly whether the deadbolt belongs on the outer doors, the inner vestibule door or both; one reply puts it bluntly: “I think a lock on the outer door is far more secure.” That is true for keeping people off the vestibule floor. The answer we give most often is both, with different jobs: a strong mechanical deadbolt or a weather-rated keypad on the outer pair, and the smart lock you use every day on the inner door.
The exception is the house that wants courier drops in the vestibule. Then the outer door has to carry the keypad, because that is the door the courier opens, and the inner door must be locked whenever a delivery code is live. We draw the plan on paper with you at the walkthrough — who comes in at each door, at what times — before choosing hardware for either.
Can a smart lock work on a pair of doors where one leaf is held shut by bolts at the top and bottom?
Yes, as long as the fixed leaf is genuinely fixed. On a pair of doors, the smart lock goes on the active leaf and throws its bolt into a strike mounted on the edge of the inactive leaf, not into a frame. That means the inactive leaf is doing the job a door frame normally does, and it can only do it if its head bolt and floor bolt are engaged firmly and the leaf cannot flex. We check those bolts, the keepers they drop into and the timber around them before anything else, because a smart deadbolt on a loose pair secures nothing.
Two details matter on older Brooklyn doors. First, the floor keeper is often worn out or filled with grit from the stoop, so the bottom bolt sits on the sill instead of in it; we clean or replace it. Second, the astragal — the strip where the two leaves meet — has to leave room for the bolt and keep a rain-tight seal. A motorised bolt that rubs against a swollen astragal will drain its batteries and eventually stall.
Where the active leaf is narrow or the original mortise lock has to stay, a surface-mounted or narrow-format smart lock is sometimes the only option on the pair. In those houses we often recommend leaving the original lock on the outer doors and putting the smart lock on the vestibule door, which is a far easier fit.
When the garden apartment's only way in and out is under the stoop, what has to stay true about that door and the areaway gate in front of it?
Both have to work as an exit first and an entrance second. For the person who lives on the garden floor, the door under the stoop and the gate across the areaway are the route to the sidewalk in a fire, so each must open from the inside in one simple motion — no key, no code, no phone, no hunting for a padlock key in the dark. That rules out the padlock-and-hasp arrangement many old gates still carry, and it rules out any lock on the garden door that needs a key inside.
Within that rule there is plenty of room. The garden door can take a keypad or fingerprint deadbolt with a plain thumb-turn inside, sealed against the damp that collects below sidewalk level. The gate can stay on a lock with an inside lever, or carry a keypad gate lock or a post-mounted strike with a push-to-exit button, cabled neatly through the areaway wall rather than across the stoop. If power fails, the inside release must still work.
Ownership of the credentials matters as much as the hardware. If the garden floor is a tenant's home, the tenant should administer the code on their own door, and the owner should hold a key for emergencies agreed in the lease rather than a live admin account. Many owners, once they see the options, leave the gate on a simple inside-lever lock and put the smart lock on the door behind it — out of the rain and cheaper.
Should the keypad face the street on the outer doors, or stay sheltered inside the vestibule?
If there is any choice, keep electronics out of the direct weather. A keypad on the outer face of a brownstone door gets driving rain off the stoop, snow piled against the door in winter and, on a south- or west-facing house, hours of afternoon sun on a dark painted surface. Outdoor-rated locks list wide operating temperatures — Schlage gives −31°F to 150.8°F outside for its Encode Plus — but a temperature rating is not a promise about water pooling in a keypad or ice in the bolt pocket.
When the outer doors must carry the keypad — usually for deliveries — we look at the door hood or lintel, the side of the door with the most shelter and the height that keeps the keypad out of splash from the stoop. A keypad set under a deep stone lintel on a north-facing house is a very different proposition from one on a flush door facing the afternoon sun, and we tell you which you have.
Inside the vestibule the problem mostly disappears. That is another reason the everyday smart lock so often ends up on the inner door: it lives in a small, dry, unheated room rather than on the street.
Historic fronts and older wood
If our original front door is too damaged to take a smart lock, what does a replacement have to look like in a Brooklyn historic district?
In a historic district, the replacement has to recall the door it replaces. The Landmarks Preservation Commission's permit guidebook says historic fabric such as doors, sidelights, transoms and door surrounds should be retained, and that staff can approve a new door at a primary facade when it matches the historic door's materials, operation, configuration, details and finish. If the door you have now is not historic, the guidebook points owners to historic doors on similar buildings for the model. Replacing a historic or special door also needs an assessment of its condition.
That is why we try hard not to put a house in that position. Most original doors can take a well-chosen smart lock, or can keep their original lock while the smart lock goes on the vestibule door. If the active leaf has been bored and re-bored by generations of locksmiths until there is no sound wood left at the lock, a door restorer can often splice in new timber before any thought of replacement. Brownstoner's long-running Brownstone Boys renovation diary, from Bed-Stuy, describes an owner who kept and stripped the original second entry door even while the outer pair had to be replaced.
If replacement is truly needed, the order of work matters: the new door is designed and approved first, and the smart lock is chosen to suit the new door's stile and thickness so it does not need altering later. We are happy to give your architect or door maker the lock's preparation drawing so the new door arrives ready for it.
Our Flatbush frame house has glass panels and a mail slot next to the lock — does that change which smart lock we should buy?
It does. Glass within reach of the inside thumb-turn invites someone to break a pane and reach in, and a mail slot near the lock invites a tool to be fed through it. The instinctive fix — a deadbolt keyed on both sides — is the wrong one, because model residential codes require a home's exit door to open from inside without a key or special knowledge, and a key you cannot find in a fire is a key you do not have.
Better answers combine three things. A smart lock with auto-lock and a thumb-turn that is hard to reach from the glass, or one that can be set so the inside turn is not trivially operated through a broken pane. Laminated or security film on the panes nearest the lock. And, on houses with a storm door, using the storm door's own lock as the first line so the glass is not the outer skin. A mail slot can be fitted with an inside hood or cage so nothing fed through it reaches the lock.
We also check the wood. Frame-house doors in Flatbush move with the seasons, and a door that binds in August will make a motorised bolt struggle. We plane or adjust the strike so the bolt throws freely in both summer and winter positions before we leave.
The shared house: owners who are also landlords
I live in my two-family house and rent out the other floor — do the city's tenant lock rules apply to us?
Some do and some do not, and the dividing line is the number of families. New York's Multiple Dwelling Law defines a multiple dwelling as a building occupied as the residence of three or more families living independently. The rules most often quoted about New York apartment locks — a tenant's right to add a lock under section 51-c, the Housing Maintenance Code's deadbolt and chain-guard list, the Tenant Data Privacy Act for smart access in multiple dwellings — are written around those buildings. A one- or two-family house sits outside that definition.
That does not leave a two-family landlord free to do anything. A tenant still lives there lawfully, the city's unlawful-eviction protections are not limited to large buildings, and the lease you signed governs locks and access. Practically, it means your tenant should have their own credential that you do not casually change, a key for their unit door, and an understanding in writing about when you may enter. For paperwork, HPD only requires a one- or two-family house to be registered when neither the owner nor a family member lives there, which is another sign that the city treats owner-occupied small houses differently.
Add a third unit and the picture changes. A three-family brownstone is a multiple dwelling, so if you are converting or already rent two floors, plan the locks as an apartment building would. We will ask how many households live in the house at the walkthrough for exactly this reason, and we suggest you confirm your own obligations with a lawyer if the answer is borderline.
Tenants keep sharing the street-door code with friends and delivery drivers — how do we tighten that without cutting off anyone's access?
Stop sharing one code, and give people the tools to share safely instead. In most small Brooklyn houses the street door started life with a single code everybody knew, and within a year it had been given to a dog walker, two exes and a takeaway driver. The fix is one personal code per adult resident, plus the ability for each resident to issue their own guest codes that expire on their own — a day, a weekend, a weekly cleaning slot.
Then retire the shared code on a date everyone agrees, with notice. Nobody should discover their code has stopped working by standing on the stoop at midnight. We set the new codes up with each household, show them how to create guest codes on their phone, and change the old code only after everyone has tested their new one. The owner keeps an admin account, but does not need to read every tenant's guest list to keep the door secure.
As the owner, can I see when my tenant comes and goes — and should I?
Most smart-lock apps will show the admin every unlock on every door, and that is exactly why owners should think before turning it on for a tenant's private door. In an owner-occupied house the owner and tenant pass each other on the stairs; a lock log that tells the owner when a tenant came home, and with whose code, turns a convenience into surveillance, and it can sour a tenancy quickly.
Our default in small houses is to keep the logs that serve security — the shared street door, the cellar, the owner's own unit — and to give each tenant sole admin of their own unit door, with the owner holding a sealed mechanical key or an emergency procedure agreed in the lease. The owner can still see that the street door was opened with a resident's code; the owner cannot see a tenant's private comings and goings.
If you do want an owner-visible log on a tenant's door, say so in the lease and keep it short. In larger buildings the city's Tenant Data Privacy Act already requires express consent before collecting such data and requires authentication data to be destroyed within 90 days unless anonymised; treating a two-family house the same way is good manners and good evidence if a dispute ever arises.
We host registered guests in our own floor of a two-family house — how do we make sure their code never reaches the tenant's floor?
Treat the house as a set of zones and give the guest exactly one route: street door, stair, host's own unit. NYC311's summary of the short-term rental rules says hosts may not rent out an entire apartment or home for fewer than 30 days, must stay in the same unit as their guests, may have no more than two guests, and must make sure every guest can reach all parts of the dwelling unit and each exit. Registration with the Office of Special Enforcement comes first. None of that gives a guest any business on your tenant's floor, in the cellar or in the yard you share with the tenant.
So the guest's code is issued for the street door and the host's unit door only, for the dates of the stay, and expires on its own at checkout. The tenant's unit door is on a credential the guest never sees; the cellar and rear-yard doors stay keyed or on owner-only codes. Because guests must be able to reach each exit, any door on their route — including the street door from the inside — opens without a code.
Tell your tenant in writing that you host and how the codes are separated; it is their front door too, and a stranger on the stair at night is less alarming when the tenant knows the plan. Whether a particular hosting arrangement is lawful is for the city to decide, not us; our part is making sure the doors behave the way the plan says.
Packages and the stoop
Can a smart lock on the outer doors stop parcels disappearing from our stoop?
It can move the parcels off the stoop, which is most of the battle. A box at the top of the steps is visible from the sidewalk and unguarded; the same box on the vestibule floor, behind a locked outer door, is out of sight and out of reach. A keypad on the outer doors with a delivery code — one that works only in daytime hours, or only on a day you are expecting something — lets a courier step into the vestibule, leave the parcel and close the door behind them, while the inner door stays locked.
Three conditions make it work. The inner door must be locked whenever the delivery code is active, so the vestibule is a sealed box rather than a hallway. The outer doors need to close and latch reliably on their own, or a courier who does not pull hard leaves the house open. And a camera on the stoop or in the vestibule turns each delivery into a recorded event, which discourages misuse of the code. Brooklyn neighbours talk about this all the time — threads on r/Brooklyn and r/parkslope ask what actually works for packages in brownstones — and lockable parcel bins on the stoop are the other common answer.
What a smart lock cannot do is stop a parcel being taken when the courier ignores the instructions and leaves it on the steps anyway. For that you need a clear delivery note on your accounts, a camera, and sometimes a conversation with the carrier. We fit the lock and the camera; the delivery note is yours to write.
Newer towers
The sponsor's team installed the smart lock on our new Downtown Brooklyn or Greenpoint condo door — how do we take the admin rights over from them?
Assume that the people who built, sold and showed the apartment may still hold a way in until you prove otherwise. Locks fitted during construction are typically enrolled by the installer or the sponsor's team, and codes are created for contractors, brokers and walk-throughs along the way. At closing you should receive the lock's admin rights, not just a code, and every code and credential you did not create yourself should be deleted.
How that is done depends on the lock. Some are standalone and need a factory reset and fresh enrolment; others are tied to the building's access platform, in which case management controls the admin side and you ask them, in writing, to remove sponsor and contractor credentials and confirm what remains. Ask, too, whether the mechanical key cylinder was keyed to a construction master; if so, a new cylinder closes that path.
We can do the reset and re-enrolment, change the cylinder, and leave you a short note listing every credential that now opens the door. On fire-rated metal unit doors we use the existing preparation and leave the corridor face matching the building standard, and we check the signal at the door, because concrete corridors are hard on Wi-Fi and Bluetooth alike.
Shops on the avenues
Our café's back door opens onto a yard — how do we lock it properly without blocking the way out?
By separating the two directions. From the yard side the door should be as secure as the front, because rear yards and alleys behind Brooklyn avenues are quiet at night. From inside, it must open in one motion without a key, code or tool whenever the premises are occupied, because in a kitchen fire it may be the nearest exit. The common mistake is a padlock, a slide bolt or a key-both-sides deadbolt added after a break-in, which secures the door by making it useless as an exit.
The usual fixes are a keypad or reader outside with an electric strike or exit device and a push bar inside, or a heavy keyless deadbolt with a simple thumb-turn inside on doors where a push bar is not practical. Staff who take out rubbish get their own codes, which can be cancelled the day someone leaves, and the door can be set to report if it is left open.
Back doors also tend to be steel in steel frames that have been hit, pried and patched over the years. We check the frame and hinges first; a new lock on a bent frame lasts weeks. Single-door keypad or reader with electric strike work is $1,500–$2,500 installed at Brooklyn's base, from the figures published on our access-control pages.
Cost on a Brooklyn house
Why can a brownstone's double doors cost more to fit than an ordinary single door?
Because the lock is the small part of the job. On a pair of tall, heavy, often original outer doors we may need to reset the head and floor bolts, rebuild a worn floor keeper, ease a swollen astragal, deal with a mortise pocket from a lock fitted a century ago, and find a keypad position that stays out of the weather — before the smart lock goes on. A single modern door in a square frame needs none of that.
Two doors in series also mean two locks and a plan for how they work together, and owners who want courier drops add a camera. That is why we quote residential doors flat after seeing them, rather than giving a number over the phone that turns out to be wrong. Building-door items — a keypad or reader with an electric strike, a new strike, a strike repair — are published figures and appear in the pricing section below.
The cheapest version of a good result is often the vestibule-door smart lock with the outer doors left on a solid mechanical deadbolt. If budget matters, ask us to price that option next to the double-door keypad and choose with both numbers in front of you.
