Install deadbolt NYC — single vs. double cylinder
Single cylinder has a thumbturn inside. Double cylinder requires a key on both sides — suited for doors with glass nearby. We walk you through what makes sense for your door before starting.
Install Deadbolt NYC — Single & Double Cylinder
Install deadbolt NYC service from Lenny Locksmith adds strong door security to front doors, apartment entries, brownstone stoop doors, and back doors across New York.
Rapid Response — 24/7 Dispatch — All Five Boroughs
Single and double cylinder deadbolt installation
High-security cylinders (Medeco, Mul-T-Lock, Assa) available
New bore holes and strikes cut when needed
Same-day NYC service
Install deadbolt NYC — the strike is the real strength
A deadbolt is only as strong as what it throws into. Builder-grade strikes held by short screws into soft jamb wood give way first in a forced entry. Every deadbolt we install gets a reinforced strike with long screws anchored into the wall stud — that detail, more than the brand on the cylinder, is what helps a door resist a kick.
High-security deadbolt options
For doors that need more than a standard deadbolt, we install high-security cylinders from Medeco, Mul-T-Lock, and Assa — pick-resistant, drill-resistant, and sold with restricted keyways so copies cannot be made at a hardware kiosk without your authorization card. A practical upgrade for ground-floor units and doors facing a hallway.
Deadbolts for back doors and basement entries
The front door gets the attention, but ground-floor back doors and basement entries are the quieter risk. We install the same Grade 1 and Grade 2 deadbolts on secondary doors, keyed alike with the front, so the whole perimeter is on one key and one standard.
Jimmy-proof deadbolts and NYC walk-ups
The surface-mounted Jimmy-proof lock is a New York institution — millions of pre-war doors carry one. They are fast to install and honest security for many doors, but they have limits. We install and replace Jimmy-proof deadbolts where they fit the door, and advise when a door deserves a bored-in deadbolt instead.
What to expect when you call
- 1
Measure and recommend
Backset, bore size, and lock style confirmed.
- 2
Install
Deadbolt and strike fitted and aligned.
- 3
Test
Bolt throw, key operation, and strike engagement checked.
Why Lenny Locksmith for Install Deadbolt in NYC
Serving all five boroughs, with a real shop in East Harlem
Strong security upgrade
Clean installation with no exposed screws
All major brands available
Same-day service in NYC
Install Deadbolt FAQs
Can I install a double cylinder deadbolt in my NYC apartment?
Check your lease first — double cylinder deadbolts may be restricted on some NYC apartment doors due to egress requirements. We can advise on hardware that works for your door and building.
Which deadbolt grade should I choose for a NYC apartment?
Grade 1 is the strongest rating and what we recommend for entry doors; Grade 2 is a solid mid-range. We show you both, explain the real differences for your door and building, and let you decide.
Can a new deadbolt use the same key as my existing locks?
In most cases, yes — we key the new deadbolt to match your current house key, or rekey everything to one fresh key while we are there.
What is a Jimmy-proof deadbolt and is it enough?
A surface-mounted lock common on pre-war NYC doors — quick to install and reasonable security for many doors. For entry doors with glass or higher risk, we usually recommend a bored-in Grade 1 deadbolt instead. We assess your door and advise honestly.
Install Deadbolt across New York City
Available in every borough and neighborhood
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