Non-destructive entry first, always - and we re-key Schlage, Kwikset, and Baldwin locks on the spot while you watch
You get a price before we start. It does not change when we arrive. No surprises.
Fast, Reliable Change Door Locks Across San Lorenzo
A Residential Locksmith - San Lorenzo service usually costs between $95 and $240 per lock, including the hardware, and most jobs are completed the same day we get the call. The bigger question for homes here isn’t just price, it’s whether the new deadbolt will actually fit original mid-century door frames without boring or jamb work. We’ve done enough lock changes in San Lorenzo to know the answer before we arrive. Call (910) 714-4287 and we’ll walk you through what your specific door needs.
San Lorenzo is a unique place to change locks. Nearly every home came from the same David D. Bohannon postwar tract, roughly 7,000 houses built starting in 1944. That means the door-prep dimensions repeat block after block, and what we learn on one street applies directly to the next. When we send a technician to your San Lorenzo home, they already know what’s behind that trim plate.
Why Dunmore Locksmith Is San Lorenzo’s Preferred Change Door Locks Company
Dunmore Locksmith has served San Lorenzo since 2007 as part of the Threshold Group family of independent local locksmith businesses. The name Dunmore comes from old words for a great fort, a stronghold built to keep what is inside safe. That’s the standard we hold for every Change Door Locks job: the person you let through the door is exactly who we said they’d be, and the lock they install is covered in writing for a full year.
Every technician we send to San Lorenzo is background-checked, identity-verified, and arrives in a clean marked uniform with a photo ID badge. Before your appointment, we send you that technician’s name and photo, so you know who to expect before you turn the handle. If anyone shows up who you weren’t told to expect, that visit is covered at no charge. That’s the Threshold Standard, and it’s non-negotiable.
Perry Osgood leads our San Lorenzo service area, and he’s built the team around one idea: written prices before work begins, every single time. No estimate that balloons, no surprise totals at the end. The price we quote on the phone is the price on the invoice.
Patio Door Lock Change in San Lorenzo
San Lorenzo Door Lock Repair for patio doors comes with a specific headache: the original sliding glass doors on Bohannon-era homes were often fitted with flimsy aluminum latch hardware that salt air has been eating for 70 years. The latch may click but not actually secure, or the handle assembly corrodes until it snaps. A typical patio door lock change here runs $120 to $220, depending on whether we’re replacing a surface-mount latch or a full mortise-style handle set.
Sliding Door Latch Replacement
On the standard mid-century sliding patio doors throughout the Bohannon tract, the original latch is usually a thin zinc die-cast piece that corrodes from the inside. We replace it with a marine-grade stainless or reinforced zinc unit that won’t seize the same way. The job takes under an hour, and we adjust the door alignment so the new latch actually engages the strike frame properly, something the original installers often rushed.
French Door Handle Set
Older ranch-style San Lorenzo homes sometimes have French or double doors leading to a rear patio. The original handle sets were never designed for daily use, and the internal springs fail, leaving the door unable to stay closed. We fit modern Kwikset or Baldwin handle sets, and because the door prep on these tract homes is uniform, the install is straightforward once we confirm the setback dimension.
Door Lock Change in San Lorenzo
Door lock change in San Lorenzo typically runs $95 to $185 for a standard knob or deadbolt replacement on an already prepped door, with the higher end covering stainless steel or high-security hardware. Where it gets more involved is on the original 1940s and 1950s doors that were never updated. Those frames were cut to old mortise specs, and modern ANSI Grade 1 deadbolts often need fresh boring in the door edge and strike modification in the jamb. That work typically adds $45 to $75 per door.
Deadbolt Upgrade on Original Doors
If your San Lorenzo front door still has the original mortise lock or a thin early pin-tumbler cylinder, don’t buy a modern deadbolt off the shelf until someone has measured the setback. Mid-century doors here are frequently cut to 2-3/8 inch backset, which some modern hardware fits fine, but the edge bore depth and strike placement are often too shallow. We handle the modification cleanly, so the new deadbolt sits flush and throws fully.
Replacing Interior Bedroom and Bathroom Locks
Interior locks on Bohannon tract homes are almost always original or near-original. The spindle wears, the latch sticks, and eventually the door locks itself when it shouldn’t. We can match new privacy knobs or levers to your existing finish, and because so many San Lorenzo homes share the same hardware style from the same narrow window, we usually have compatible parts on the truck.
Trusted Brands We Service in San Lorenzo
We’re factory-authorized to install and service hardware from Schlage, Medeco, Kwikset, Yale, Baldwin, Mul-T-Lock, Sargent, and Abloy. For San Lorenzo specifically, we lean heavily on Schlage stainless steel deadbolts and Medeco or Mul-T-Lock cylinders where homeowners want real bump-and-pick resistance. We carry the common finishes, backset sizes, and strike plate profiles that match this neighborhood’s door-prep on the truck, so most lock changes are done in one visit. No ordering and waiting, no second trip fee.
Common Change Door Locks Problems We See in San Lorenzo Homes
- Salt-corrosion seizures on exterior deadbolts. Persistent marine fog off the southern San Francisco Bay deposits salt that works into cylinder pins and strike plates. Locks that haven’t been serviced in years seize completely, often with the key stuck mid-turn.
- Original mortise locks that eat keys. Bohannon-era mortise locks were not designed for modern duplicated keys. The internal levers and springs wear until the key won’t turn at all, and the only real fix is replacement or mechanical rekeying.
- Modern deadbolts that won’t fit 1940s door prep. Homeowners buy a Grade 1 deadbolt, then discover the original door was bored for a thinner, shorter lock body. We re-bore the edge and mortise the strike to modern specs without splintering the frame.
- Patio door latches that click but never lock. The original zinc latches on tract-home sliders corrode internally until they catch but don’t seat. A visual check looks fine; the security is gone. We replace them with stainless or marine-grade reinforced hardware and realign the door.
Pricing for Change Door Locks in San Lorenzo, CA
Here’s what San Lorenzo homeowners should expect to pay:
| Job | Typical Price Range |
|---|---|
| Standard knob or deadbolt replacement (hardware included) | $95 – $185 |
| Patio sliding door latch replacement | $120 – $220 |
| Full handle set on French or double doors | $150 – $240 |
| Deadbolt upgrade on original mid-century door (requires boring + strike modification) | $140 – $260 |
| Mechanical rekey of existing lock (no new hardware) | $35 – $65 per cylinder |
We quote the full price on the phone before anyone is dispatched. That price is the price on your invoice. There is no call-out surcharge added on arrival, and the quote includes all labor, hardware, and any minor jamb or strike adjustment. If you want a written estimate before you commit, we’ll send it. Call (910) 714-4287 and we’ll tell you exactly what your San Lorenzo lock change will cost. Written prices, every time.
We Also Serve Cities Near San Lorenzo
Our San Lorenzo crews also cover Change Door Locks in San Lorenzo neighborhoods, plus nearby Castro Valley, San Leandro, Union City, and Oakland. Same written pricing, same background-checked technicians, same 365-day guarantee on every job. Dispatch is coordinated from our San Francisco Bay Area office, with technicians staged locally so response to San Lorenzo stays tight.
Serving San Lorenzo, CA - Our Local Coverage Area
We’re based in the San Lorenzo area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About Change Door Locks in San Lorenzo
Yes, and we do this constantly in the Bohannon tract. The original mortise lock body comes out, and we bore the edge of the door to accept a standard modern deadbolt, then cut and reinforce the strike plate in the jamb. The work is clean and leaves the door face intact. On a 1940s ranch door, expect the full job to run $140 to $260 including hardware. Call (910) 714-4287 and we’ll give you an exact figure for your specific door.
Oil attracts dust and salt particles, which is the opposite of what San Lorenzo’s marine fog needs. Salt-laden air from the southern Bay corrodes the internal pins and springs, and oil just turns that corrosion into sticky paste. The real fix is either a full cylinder clean with a proper solvent or replacement with a stainless steel or marine-grade lock. If your lock has seized more than once, it’s done. Call us and we’ll fit a lock that survives this air.
Usually yes, if the cylinder is still mechanically sound. We rekey the internal pins so your old keys no longer work, which runs $35 to $65 per cylinder in San Lorenzo. But if the original mortise mechanism or early pin-tumbler has internal wear, rekeying just delays the inevitable. We’ll tell you honestly which one you’re dealing with, y no charge for the assessment when you schedule the work.
Schlage stainless steel deadbolts are our default for San Lorenzo exterior doors because the finish and internals hold up to salt air better than brass or standard zinc. Medeco and Mul-T-Lock cylinders are what we recommend if you want true pick and bump resistance. For patio doors, we lean on reinforced stainless latches rather than zinc. Call (910) 714-4287 and we’ll spec the right hardware for your specific doors.
Yes, patio door lock change is one of our most common San Lorenzo calls. The original latches on Bohannon-era sliding doors were thin zinc castings and they corrode from the inside out in this climate. We replace them with marine-grade stainless or reinforced hardware, and realign the door so the latch actually engages. Typical cost is $120 to $220, quoted in writing before work begins.
An Insider’s Look at San Lorenzo’s Lock Problem
Because nearly every San Lorenzo home came from the same Bohannon postwar tract, about 7,000 houses built from 1944 on, the original door-prep dimensions and outdated mid-century lock hardware repeat block after block. That’s why we so often find ourselves boring or modifying jambs to accept modern deadbolts just to fit basic hardware. You can’t buy a new lock at the hardware store and expect it to drop into a 1948 door frame. The original prep is too shallow, the strike too small, the edge bore too narrow. This is not a quirk of your house. It’s a quirk of the entire city.
On a foggy morning in the Bohannon tract near San Lorenzo High, we were called to a 1948 ranch where the front door still had its original mortise lock. The exterior trim and strike were pitted from years of salt-laden air, and the key wouldn’t turn. Our tech freed the cylinder with a non-destructive entry, then replaced the old lock with a stainless steel Schlage deadbolt after boring the jamb to modern specs. A week later, the neighbor two doors down called with the exact same frozen mechanism, because the original door-prep is that uniform. That’s San Lorenzo for you. The same failure, street after street, on locks that are pushing 70 to 80 years old.
Call Dunmore Locksmith for Your San Lorenzo Door Lock Change
You deserve to know exactly who is coming to your door before you open it. We send that person’s name and photo to your phone before the visit. The price is in writing before any work starts, and it’s covered by the 365-Day Done Right Promise: if the repair fails, we return at no charge. This is what we’ve done for San Lorenzo since 2007. Call (910) 714-4287 now and get a free, exact quote for your lock change. A live person answers the phone, any hour of the day or night.
Written by Perry Osgood, Owner at Dunmore Locksmith, serving San Lorenzo since 2007.






