Rekey or Replace? The Honest Answer for Most Homes

Rekey, in most cases. Rekeying changes the small pins inside the cylinder already on your door so the lock accepts a new key and refuses every old one, and the hardware never leaves the door. If that hardware is sound, you end up with exactly the security you had, minus every key you cannot account for. Replacement is the honest answer only when the lock itself is the problem.

That is our position on residential work in Evansville, and it deserves an argument rather than an assertion. “Just put new locks on it” sounds like the safer choice, and usually is not. Here is what each route actually does, and how to tell which one your door needs.

A house lock keeps its combination in a stack of small pins inside the cylinder, and the cut of the correct key lifts those pins to a line. Rekeying swaps that set for a different one. The lock body, the bolt, the strike, and the door are untouched.

The consequence is what matters to a homeowner: old keys stop working. Not “probably” — a key cut to the old combination will no longer turn that cylinder. Whoever held one holds a piece of metal. That is the outcome new hardware gives you, without buying new hardware.

What rekeying does not change is the condition of the cylinder, or anything about the door it is mounted in. A worn lock rekeyed is a worn lock with a new key. That limit is the whole basis for the cases below.

Most calls that start with “should we rekey or replace” are not about a threat at the door. They are about an unknown number of keys in circulation. New owners inherit a list they never see: the builder, the agent, the lockbox, a cleaner, a contractor, whoever the previous owner handed a spare to. Better hardware does not answer that. Changing the combination does.

There is federal data behind that. The Bureau of Justice Statistics report Victimization During Household Burglary is the most recent federal work that breaks burglaries down by how the offender actually got in. Looking at burglaries of unoccupied homes where no force was used, it found 40 percent of offenders entered through an unlocked door or window and 17 percent through one standing open. Eight percent used a key to the residence.

Read the category carefully — that is the no-force group, not every burglary. What it says about our trade is still plain. When a home is entered without force, the failure is almost never the lock. It is a door left open, or a key somebody already had.

We at A-1 Lock & Safe have been rekeying houses across the Tri-State since 1983. Our own call log says the same thing: the customer who thinks they need new locks usually needs new keys.

These are the situations where rekeying is not the budget option — it is the correct one:

• You just closed on a house. The hardware is usually fine and the key history is not. A whole-house rekey retires every key the property ever issued.
• A rental turned over. The previous tenant may have returned two keys and cut four. Rekeying between tenants is routine property maintenance rather than an accusation about anybody. Whether it is required at turnover is a question for the lease, and a tenant who wants their own locks changed should raise it with the landlord first.
• A key went missing. A lost keyring, a stolen purse, a key that never came back from whoever borrowed it. If the key was on a ring with anything identifying the address, treat it as a key somebody else now holds.
• The household changed. A roommate moved out, a relationship ended, a caregiver arrangement finished. The lock does not need to be stronger. It needs to be different.
• You have too many keys. Front door, back door, garage entry, storm door, each on its own key. Rekeying is what puts them all on one.

That last one deserves pulling out, because it is the thing rekeying does that a shelf purchase does not. Cylinders sharing a keyway can all be pinned to one key — keyed alike, in the trade’s phrase. It is the principle behind a commercial master key system, scaled to one house. Four new deadbolts out of four boxes arrive on four different keys until somebody pins them to match.

The narrower set. We do replace locks, and we say so plainly when it is warranted:

• The cylinder is worn out. A key that has to be jiggled or held at an angle is telling you something. New pins in a tired cylinder buy you very little.
• The lock was damaged. Hardware that survived a past forced entry, or a previous lockout handled destructively, is replaced rather than rekeyed.
• The grade is wrong for the door. A builder-grade knob on a door that ought to carry a deadbolt is not a rekeying problem. Hardware is graded on tested performance rather than looks: the residential deadbolt standard, ANSI/BHMA A156.40, runs a Grade A deadlatch through 400,000 cycles and loads the door against the bolt with 1,350 pounds.
• Weather has taken it. Corrosion on an exterior cylinder is not cosmetic and not a matter of opinion — the same standard evaluates it with a salt spray test. A lock that has gone gritty and green in Ohio River humidity has failed on an axis the standard actually measures.
• The keyways do not match. When you want one key for every exterior door and one door carries a different brand or a different keyway, that piece of hardware has to change to join the set.
• Parts are gone. Some discontinued residential lines cannot be sourced any longer. When the pin kit for a cylinder no longer exists, the decision is made for us.

Notice what is not on that list: age by itself, or a finish that a big-box display makes look outdated. A twenty-year-old deadbolt that throws smoothly into a solid strike is a better lock than a new one hung in a loose jamb.

One correction while we are here, because the advice online is nearly unanimous and still muddled. The numbered Grade 1, 2, and 3 scale that consumer articles tell homeowners to shop by comes from BHMA’s general product-grade system. For certified residential hardware, BHMA points buyers to a separate residential rating. Both scales are real, they are not interchangeable, and a bare number tells you little on its own.

Half of the “broken lock” calls we take are not lock calls. The door has sagged on its hinges, the strike has drifted, or the slab has swollen in Ohio River humidity. The symptom reads as a lock problem — the bolt will not throw, the key fights you, the door has to be pulled hard before it will lock. The cause is alignment.

This is not folk wisdom. This Old House, walking homeowners through realigning a deadbolt and strike plate, names the causes plainly. Frames shift as wood-frame houses settle, temperature swings make wood expand and contract, and worn hinges let the door sag. Each of those moves the bolt relative to the hole it has to find.

Neither answer to the rekey-or-replace question fixes that. A new deadbolt in a misaligned door binds exactly the way the old one did, and you have paid for hardware to solve a hinge problem. So we look at the door before we quote the lock, in Evansville and in the towns we cover. That is frequently the cheaper conversation.

We will not publish numbers, because a published number becomes a quote we have to honor on a door we have never seen. What moves it is the same list our residential page carries:

• How many cylinders. Rekeying is priced per cylinder on top of one service call, so a whole-house job costs less per lock than a single door. Count them before you call and we can quote it on the phone.
• Rekey or replace. This is the fork. Rekeying is labor and a handful of pins; replacement is that same labor plus the hardware itself, per opening.
• Hardware grade. Builder-grade knobs, mid-grade residential deadbolts, and commercial-grade hardware for a rental all price differently, which is why the grade conversation belongs before the purchase rather than after.
• Door condition. A door needing a strike moved or a mortise cleaned up is more work than a straight cylinder swap, and we would rather say so on the phone.

The economics follow from that list. Rekeying and replacing share most of their labor, and replacement adds a hardware cost at every opening. That is the whole reason rekeying wins whenever the hardware is not the problem — and the reason it stops winning the moment it is.

Work each exterior lock with the key you have. If the bolt throws smoothly and the key turns without argument, the hardware is not your problem. The key list is, and rekeying is the answer. If the key fights or the cylinder feels gritty, say so on the phone and we will look at whether it is the lock or the door.

Either way, you should hear the reasoning before you hear a price, and the reasoning should survive being questioned. Call, tell us how many doors you have and what shape they are in, and we will tell you which of these two jobs yours actually is.

None of this is legal advice. What a landlord or a tenant in Indiana may do about locks is governed by the lease and by Indiana law, and a specific dispute is a question for an attorney or the local court.