Keyed-Both-Sides Deadbolts in Claremont: Where They Fit and Where They Don't

Double Cylinder Deadbolt Installation in Claremont: what to expect

Fitting a double cylinder deadbolt is mostly standard door work with a few extra details. The door needs a 2-1/8-inch bore through the face and a 1-inch bore in the edge, a backset of 2-3/8 or 2-3/4 inches, and a thickness the lock supports, usually 1-3/8 to 1-3/4 inches; thicker doors need an extension kit. The interior cylinder sits farther out than a thumbturn, so we check clearance for curtains, door stops and security screens. Both cylinders are keyed alike, and high-security options from Medeco, Mul-T-Lock or ASSA Abloy add restricted keys that limit copies of the one key everyone depends on. The strike matters just as much: a box strike with 3-inch screws into the framing. We finish by testing from both sides with the key and agreeing where the key will live. If the glass sits too close to the bore or the stile is narrow, we explain the options before we drill, so nothing gets cut that cannot be undone.

How we can help in Claremont

• Interior storage rooms and secured closets. Rooms holding records, equipment or wine often need a lock that can't be turned from inside by a child or guest. A keyed-both-sides deadbolt does that. We install one on rooms that aren't sleeping spaces and aren't on an escape route, and we keep the keying simple.
• Swapping a double cylinder for a single cylinder. If you inherited a double cylinder deadbolt, lost the key or recognized the exit risk, we can replace it with a single-cylinder deadbolt keyed to your house key. The bores are the same, so it's a quick swap, and we'll point out ways to protect the glass instead.
• Thick doors, French doors and narrow stiles. A French door's stile has to hold a hole roughly two inches across plus a latch pocket, with room to spare beside the glass stop. We measure stile width and thickness before quoting. If the stile is too narrow, we say so and suggest a surface-mounted or narrow-stile lock instead.
• High-security and restricted-key double cylinders. A double cylinder concentrates risk in one key, so key control matters more. High-security cylinders resist picking and bumping and limit duplication to authorized holders. They cost more than standard locks, and we help you judge whether the door warrants it.
• Safer alternatives when a double cylinder is the wrong fit. Sometimes the best answer to a glass door is a single-cylinder deadbolt plus protecting the glass. We install the lock, keep a thumbturn inside and talk through laminated glass, security film and decorative grilles, which glaziers and film installers handle. That blocks the reach-in without trapping anyone.

How Claremont shapes the job

In family neighborhoods across Claremont, kids, guests and busy mornings make a key-to-exit lock hard to live with. Children can't always find or turn a key, and visiting grandparents have never seen it. For the front and garage-entry doors we recommend single cylinders. A double cylinder can work on a detached garage door or a storage room where nobody needs a quick way out.

Older homes in Claremont frequently have wood doors with divided glass panes close to the lock, and some already carry a double cylinder from a previous owner. These doors are often the main exit, so we usually recommend a strong single-cylinder deadbolt and laminated glass in the pane nearest the lock. For a rear door that isn't the main route, a double cylinder can make sense. We check stile width before drilling, since old wood can split.

Hillside and foothill homes near Claremont face wildfire evacuation risk and sometimes steep exterior stairs, so a quick exit matters. Smoke and darkness make the seconds a key hunt takes dangerous. A double cylinder on the main exit is a poor trade. We recommend a standard deadbolt on main exits and keep any keyed-both-sides locks for outbuildings that aren't part of an evacuation route.

Common situations

• A bungalow has a brass mail slot cut into the front door about eight inches from the deadbolt's thumbturn. The owner has read that a hooked wire fished through a slot can turn some thumbturns. A double cylinder would solve it but trap the household. We suggest sealing or relocating the slot, using a catch box, or mounting the deadbolt higher, and keep a normal thumbturn on the door.
• A homeowner installed a double cylinder deadbolt years ago and keeps the key in the lock whenever someone is home. We point out the contradiction: a key sitting in the interior cylinder is exactly what a hand reaching through broken glass would turn. She chooses a single-cylinder deadbolt and laminated glass for the nearest pane, which solves the key problem and the glass problem.
• A 1920s Craftsman near The Webb Schools and Raymond M. Alf Museum of Paleontology has a front door with nine small glass panes and a thumbturn deadbolt six inches from the nearest pane. The owner asks for a double cylinder. We explain that this is the home's main exit, so a lock needing a key to leave conflicts with exit guidance. We install a strong single-cylinder deadbolt with a box strike instead, and she calls a glazier about laminated glass for the pane nearest the lock.
• A host with a guest house near Thompson Creek Trail wants a double cylinder so visitors can't leave doors unlocked from inside. We explain why guests, who don't know the key plan, are the people most at risk in a fire. We install a keypad deadbolt with a keyed override and an inside thumbturn instead, so codes change between stays and nobody searches for a key in the dark.

From your call to the finished job

1. Talk through the door and the reason. Call (951) 903-3193 and tell us which door it is, what it's made of, where the glass sits and why you want a keyed-both-sides lock. A couple of photos help. We ask whether another exit exists, because that answer shapes everything that follows.
2. Check exits, glass and the people involved. This step separates a sound installation from a bad one. We confirm another exit exists, count the people who'd need to use it, and talk through the key plan. If we recommend against the lock, we say so before any drilling begins.
3. Measure, quote and choose the hardware. We measure door thickness, backset and stile width, then pick a deadbolt that fits: standard thickness, a thick-door kit or a narrow-stile alternative. You see grade and finish options and get a quote before any hole is drilled.
4. Prepare the door. We use a drill jig to cut the face and edge bores square, protecting the glass and finish with tape and padding. If the door is already bored, we clean and check the holes. A crooked bore makes the key bind, so we take care here.
5. Fit both cylinders, key them and set the strike. The two cylinders are tightened evenly, the bolt is adjusted for the backset and the keying is matched to your existing key or a new one. A heavy strike goes into the jamb, and we check the hinge side, because glass doors often give way at the hinges.
6. Test the lock and plan the key. We test the lock several times from both sides with the door open and closed. Then we agree on the key plan: where the key hangs inside, out of reach from outside, and who knows where it is. You get spare keys and a short checklist.

Pricing factors

• Lock grade and brand. Double cylinder deadbolts come in standard, Grade 2 and Grade 1 versions, and the heavier the lock, the higher the price. Brand and finish matter too. We show two or three choices that fit your door and explain what each adds beyond price.
• Glass protection you add separately. If you pair a single cylinder with protected glass, budget for both. We handle the lock and hardware, and a glazier handles the glass. Sometimes that combination costs more than a double cylinder, but it keeps a thumbturn on the inside.
• Number of doors and scheduling. Doing several doors in one visit, such as a workshop door and a side door, saves travel and setup. Thick or custom doors, restricted keys and unusual finishes raise the total. We list each door in the quote so you can approve them one at a time.

Every job gets a clear quote before any work starts. Call (951) 903-3193 with the details and we'll tell you what to expect for your situation in Claremont.

What not to do

• Installing one in a rental without telling the landlord. Leases usually restrict lock changes, and a double cylinder raises exit-safety concerns for the owner. Tenants may be asked to remove it at their own cost. Ask in writing, and propose a heavier strike or protected glass instead.
• Using a double cylinder on a bedroom or an only-exit door. Bedrooms and the only route to an exit need to open without a key. A keyed-both-sides lock there can trap people, especially kids, during a fire, a medical emergency or an ordinary lockout from the wrong side.
• Giving out one key and no plan. A single key hung on a nail that only one family member knows about leaves everyone else dependent on that person. Spread the knowledge: everyone who lives there needs to know where the key is and how to use it.

What to do before we arrive

• Practice getting out. With the door locked, walk from the farthest room to the door in the dark and use the key. Do it with children and guests too. If it takes more than a moment, rethink the plan or the lock. Repeat the drill whenever the household changes.
• Match the lock to your door thickness. Most double cylinder deadbolts expect 1-3/8 to 1-3/4 inches. Thicker doors need an extension kit, and kits are model-specific. Measure the door edge rather than the frame, and photograph the existing bores. We can bring the right kit if you give us the number.
• Tell every adult in the household, and any regular visitors, where the key lives. A babysitter, a house guest or an older relative who has never seen the lock should be shown on arrival. A note taped inside a cabinet door can help, as long as it isn't visible from outside.
• If you rent, don't swap in a double cylinder without written permission. Many leases restrict lock changes, and landlords carry exit and liability concerns of their own. Ask about reinforcing the strike or protecting the glass instead; those requests usually meet less pushback. Keep any approval letter with your lease.

Getting to Claremont

Claremont is about 30 miles from our San Bernardino base, roughly 34 minutes in light traffic via University Parkway to I-215 South. When you call, you get an arrival estimate based on where the technician is and the traffic at that moment.

Most trips into Claremont use Mount Baldy Road for at least part of the drive, and the technician keeps an eye on live traffic along the way so the arrival estimate you heard on the phone stays honest.

About Claremont: Claremont was laid out in 1887 as one of roughly 30 town sites along the new Santa Fe line between San Bernardino and Los Angeles, and it incorporated on October 3, 1907.

New or replacement locks in Claremont?

Call (951) 903-3193 and tell us which doors and what kind of hardware you have in mind. If you already bought the lock, keep the box handy so we can check it fits the door, and we'll quote the install before any work starts.