Most front doors in Louisville have a doorknob lock. Many homeowners assume that’s enough. It usually isn’t — and understanding why comes down to knowing what a deadbolt actually does that a knob lock can’t.
Bowles Locksmith Service Louisville has been working on residential doors across Jefferson County for over 31 years. The pattern we see repeatedly: homeowners who thought their existing lock was sufficient until they needed to call us after the fact.
What Is a Deadbolt and Do I Really Need One in Louisville?
A deadbolt is a lock with a solid metal bolt that extends from the door into the door frame when you turn a key or thumb turn. Unlike a spring latch — the angled bolt in a standard doorknob — a deadbolt doesn’t retract unless you manually turn it. That single mechanical difference matters a great deal in practice.
Standard doorknob latches are spring-loaded. The bolt has an angled face that lets the door close without a key. That same angled face can be pushed back with enough lateral pressure. A deadbolt has no angled face. The bolt is square and sits fully extended inside a metal strike plate anchored into the door frame. Without turning the lock mechanism, that bolt does not move.
Do you need one in Louisville? Yes, practically speaking. Kentucky has no law requiring deadbolts on residential properties, but Louisville Metro Police Department consistently recommends them in home security guidance. Any residential door that serves as a primary entry point — front, back, garage entry — should have a deadbolt. The knob lock alone offers minimal resistance to a determined forced entry.
How Deadbolts Are Rated — and Why the Grade Matters?
Not all deadbolts perform the same. The American National Standards Institute (ANSI) and the Builders Hardware Manufacturers Association (BHMA) grade residential deadbolts from Grade 1 through Grade 3.
Grade 1 is the highest residential rating. These locks are tested for hundreds of thousands of open/close cycles, resistance to impact, and bolt strength. Grade 3 is the lowest — many budget deadbolts sold at big-box stores fall into this category.
When a homeowner asks which lock to buy, the answer from a practical standpoint is Grade 1 whenever possible, especially for front doors and exterior entries that see the most exposure. Grade 2 is a reasonable middle ground for secondary entries. Grade 3 locks on a primary entry door offer limited real-world improvement over a knob latch alone.
The ALOA Security Professionals Association publishes guidance for consumers on evaluating lock quality, including grading information that can help you compare products before buying. It’s worth consulting before you spend money on a lock that won’t perform under stress.
Single Cylinder vs. Double Cylinder
A single cylinder deadbolt uses a key on the exterior and a thumb turn on the interior. This is the most common configuration for residential use in Louisville homes, and for most situations, it’s the right choice.
A double cylinder requires a key on both sides. Homeowners sometimes choose this for doors with glass panels, reasoning that someone couldn’t break the glass and reach in to turn a thumb turn. That logic holds in theory, but double cylinder locks also mean you can’t exit quickly in an emergency without a key. Kentucky fire safety guidance recommends against double cylinder deadbolts on primary exit doors for this reason. If you have a door with glass near the lock, the better solution is a door replacement or a glass break sensor — not a lock configuration that slows your exit.
What a Strike Plate Actually Does?
A deadbolt is only as strong as what it’s anchored into. The standard strike plate installed on most new construction homes uses screws that are three-quarters of an inch to one inch long. Those screws go into the door jamb wood, not the structural framing behind it.
A reinforced strike plate with 3-inch screws reaches past the jamb and into the wall stud. This one change — often costing less than the deadbolt itself — significantly increases how much force a door can absorb. We see doors in Louisville regularly where a quality deadbolt has been installed with the original short-screw strike plate, which undercuts the whole investment.
If you’re having a deadbolt installed or inspected, ask specifically about the strike plate and screw length. A professional from Bowles Locksmith Service Louisville will assess both the lock and the frame during a residential service call.
Deadbolts and Rekeying After a Move
One situation that comes up often: homeowners buy a house in Louisville and want to know if the existing deadbolt is good enough to keep. The lock might look solid, but if the previous owners had copies of the key made over years — contractors, family, neighbors — you have no real control over who can enter your home.
This is where a house lock rekey Louisville service makes sense. Rekeying changes the internal pins of the lock cylinder so the old keys no longer work, without replacing the hardware. If the deadbolt itself is in good condition and meets Grade 1 or Grade 2 standards, rekeying is a practical and efficient option. If the lock is worn, outdated, or Grade 3, replacing it is the smarter move.
Smart Deadbolts: Useful Addition, Not a Replacement for Fundamentals
Electronic and smart deadbolts have become popular in Louisville homes, particularly with keypad entry and app-based access. They do offer genuine convenience, especially for households managing multiple people coming and going.
The mechanical quality standards still apply, though. A smart deadbolt should carry a Grade 1 or Grade 2 ANSI/BHMA rating. The electronic component adds convenience; the physical bolt and strike plate still carry the structural load. Also consider battery reliability — most keypad locks have a backup key override, and keeping a physical key for that scenario is important.
Getting This Right the First Time
The Better Business Bureau recommends using accredited businesses for home security work — Bowles Locksmith Service holds an A+ BBB rating. When you hire a qualified locksmith rather than doing it yourself, you get a professional who will check door alignment, test the bolt throw length, confirm the strike plate is properly anchored, and flag any frame damage that would undermine the install.
Our Louisville team serves Jefferson County and the surrounding area, including Bullitt, Hardin, and Meade Counties in Kentucky, plus New Albany and Floyd County in Indiana.
If you have questions about your current deadbolt, need a new one installed, or want to rekey locks after a move, contact us online or call (502) 935-2614. You can also visit us in person at 5320 Valley Station Rd, Louisville, KY 40272.
See what Louisville homeowners say about working with us in our client reviews — over three decades of residential locksmith work speaks for itself.