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Julian's Locksmith

Charter Oak, Los Angeles County

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

Short answer: Before installing a double cylinder deadbolt in Charter Oak, we ask what the door is for, how far the lock sits from glass and whether another exit exists. Sometimes a single cylinder with laminated glass or security film is safer. If a double cylinder fits, we install and key it. Call (951) 903-3193 any day between 6:30 a.m. and 11:30 p.m.

Double Cylinder Deadbolt Installation in Charter Oak, CA — Deadbolt installation with reinforced strike plate

A double cylinder deadbolt is really two decisions: the lock and the plan for the key. The lock part is mechanical and easy, with two cylinders keyed alike and a heavy bolt. The plan is harder, because the key has to be out of reach from outside and instantly available from inside, for adults, kids and guests, in the dark. Julian's Locksmith handles both halves. We install the deadbolt, then walk through placing the key, spare copies and what to do when visitors stay over. For Charter Oak customers, the work starts with a quote and a conversation, not a drill. Call (951) 903-3193.

What to know first in Charter Oak

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.

Work included on a typical visit

  • Double cylinder deadbolt installation on glass-panel doors. Wood doors with decorative lites, French doors with wide stiles and doors with small windows near the latch are all candidates. We assess the glass distance, mark and drill with a jig, fit both cylinders and test the throw into the strike. You see the lock work from both sides.
  • Exit and code check before we drill. Before drilling, we look at where occupants would leave in a fire, whether this door is the main route, and who lives or works inside. Building and fire codes drive the answer, and local departments enforce them differently. We won't fit a lock that traps people, and we say so before quoting.
  • Keying, spare keys and the key plan. We key the new cylinders to your existing keyway, such as Kwikset KW1 or Schlage SC1, or to a fresh key. For properties with many doors, a keyed-alike plan saves keys. For high-security options, restricted blanks limit copying of the one key everyone relies on.
  • Thick doors, French doors and narrow stiles. Custom doors, 2-1/4-inch entries and doors with leaded or beveled glass need extra care. A thick-door kit with longer tailpieces and screws handles the thickness, and a drill jig keeps the bore clean. We work from existing prep where possible and protect the glass and finish while we work.
  • Strike, jamb and frame reinforcement. Glass doors often sit in lighter frames than solid entries. Our installation includes checking frame condition, replacing short strike screws and adding reinforcement where needed. We explain what each addition does and what it costs before we do it, and nothing gets added without your say-so.

What's different about Charter Oak

Shops in Charter Oak's strip centers usually have aluminum storefront doors with narrow stiles that can't take a standard bore, plus rear doors that serve as the second exit. A double cylinder typically isn't an option on an exit door. We use hookbolt deadlocks, exit devices and code-compliant keyed locks, and suggest film or laminate on glass near the lock. We never trade away exit capacity for security.

Older homes in Charter Oak 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.

Apartment tenants in Charter Oak often ask about double cylinders after a break-in on a balcony or glass door. In a rental unit, the main entry must keep working deadbolt hardware under California law, and tenants need to leave without a key in an emergency. We usually recommend reinforcing the strike, protecting glass and asking the landlord to approve any lock changes. Landlords can call us to remove an unauthorized double cylinder at turnover.

Example situations

  • A small business near Cienega Avenue keeps payroll records and electronics in a storage room with a glass transom. The owner wants a double cylinder so nobody can lock themselves in or turn the lock from inside. We confirm the room isn't an exit path, install a Grade 1 double cylinder deadbolt keyed to the owner's system, and point out that the lightly built door is now the weak spot.
  • A host with a guest house near St. Nectarios Greek Orthodox Church 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.
  • The owner of a boutique has a glass-panel rear door with a thumbturn within reach of the pane. Employees use that door to leave, and it opens onto an alley. A double cylinder would slow an emergency exit. We install a Grade 1 single-cylinder deadbolt with a heavier strike, keep the thumbturn, and suggest security film on the glass so the front and alley doors keep their exit capacity.
  • A daughter in Charter Oak asks about a double cylinder on her father's door because he has started wandering at night. We explain the fire risk: if he can't get out, neither can anyone helping him. We suggest door chimes, a different lock layout and a talk with his care team. We aren't care specialists, but we can help you find a lock that doesn't create a trap.

From your call to the finished job

  1. Talk through the door and the reason. Before we drive out, we ask three things: which door, how far the glass is from the thumbturn, and whether this is the way out in an emergency. Those answers tell us whether to bring a double cylinder, a single cylinder or both, so you can choose on site.
  2. Check exits, glass and the people involved. On site, we look at the door, the glass and the exit routes, and verify ID and proof that you own or live at the property. We decide together whether a double cylinder suits this door. If it doesn't, we explain what to do instead.
  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. We mount the bolt, then fit the exterior and interior cylinders through the tailpiece, aligned so the keyway sits upright when unlocked. Both are keyed alike to your key. Then the strike goes in: a box strike with 3-inch screws into the framing.
  6. Test the lock and plan the key. The visit ends with an actual drill: door locked, key at the planned spot, you walking from the far side of the room. If that feels slow, we rethink the plan or the lock. We hand over keys and note the keyway and brand for your records.

What affects the cost

  • Lock grade and brand. The lock itself is the first line of the quote. A solid mid-grade double cylinder suits an outbuilding, while a Grade 1 or restricted-key unit suits a higher-risk entry. We quote the specific model so you can compare it with a different grade.
  • Keys and keying. Decide how many keys the household needs and where each one lives. Since the key is the way out, an extra copy for the key hook and one for a spare spot are common. We include whatever count you choose in the quote.
  • Glass protection you add separately. Laminated glass, security film and grilles aren't part of our lock work. Glaziers and window-film installers handle them, and they have their own costs. We install the lock and strike, and we can tell you what to ask those trades for.

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 Charter Oak.

Practical tips before you call

  • Review the setup every year. Kids grow, guests come and go, and keys get moved. Walk through the exit drill again, check that the spare still works and make sure the key hook is where you left it. A small annual check keeps the lock from turning into a hazard.
  • Don't count on a spare key under a mat or in a flowerpot for a keyed-both-sides door. It's the first place a burglar looks, and it doesn't help anyone leaving from inside. Leave the spare with a trusted neighbor or relative, or in a lockbox with its own code.
  • Consider laminated glass or security film first. Either one targets the weakness without changing how the lock works. A glazier can replace the pane nearest the lock, and a film installer can add a layer to existing glass. Pair that with a strong single-cylinder deadbolt and a long-screw strike.
  • Measure the real distance. Picture an arm reaching through a broken pane and see whether it can touch the thumbturn; if it can't, a double cylinder adds nothing. Measure from the nearest glass edge to the thumbturn, and from the glass to the door's far side. Tell us both numbers when you call.

What not to do

  • 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.
  • Putting a double cylinder on the main exit and hiding the key far away. In a fire, that costs seconds nobody has. Households do it because a pane of glass worries them. Protect the glass instead and keep a normal thumbturn on the door your family relies on to leave.
  • Skipping the strike. People focus on the interior cylinder and leave a thin strike held by short screws. A hard kick pops a short-screwed strike out of the jamb, and the double cylinder never gets a chance. Fit a box strike with 3-inch screws into the framing at the same visit.

Service in Charter Oak

Charter Oak is about 38 miles from our San Bernardino base, roughly 43 minutes in light traffic via Palm Avenue to I-215 North, I-15 South. When you call, you get an arrival estimate based on where the technician is and the traffic at that moment.

Our path into Charter Oak depends on where the previous job wrapped up. Sometimes that's a straight run via Arrow Highway; other times it's surface streets the whole way. Either way, you get a heads-up call when the technician is close.

About Charter Oak: Charter Oak's school district dates to 1894, when Charter Oak School opened in a tent with 24 students before moving into a one-room schoolhouse that November.

NeighborhoodsCharter Oak Park blocks, Bonnie Cove Avenue corridor, Lyman Avenue and Sunflower Avenue area, Arrow Highway frontage along the Glendora line, Cienega Avenue tracts near the Charter Oak Unified district office, Tudor Street and Greenhaven Street
ZIP codes91724
Main routesI-210, SR-57, Arrow Highway, Covina Boulevard
From our San Bernardino baseabout 38 miles via Palm Avenue to I-215 North, I-15 South, then the Foothill Freeway (SR-210) West, which becomes I-210 at the SR-57 junction, to the Sunflower Avenue exit in Glendora and south on Sunflower Avenue to Arrow Highway; the Grand Avenue exit suits the west side

New or replacement locks in Charter Oak?

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.

Frequently asked questions

Is there a smart version of a double cylinder deadbolt?

Not in the usual sense. Keypad and smart deadbolts replace the outside key with a code or app and keep a thumbturn inside, so they remove the key-hunt problem but not the glass-reach problem on their own. Pair one with protected glass and a strong strike. We install Schlage, Yale and Kwikset models with a keyed override for dead batteries.

Can you rekey a double cylinder deadbolt?

Yes. Both cylinders are pinned to the same key, so we rekey both to your new key. If one cylinder is worn or the key is lost, we can also replace the whole lock. We verify ownership before rekeying and quote first. The job takes only slightly longer than rekeying a single cylinder.

Is a double cylinder more secure than a single cylinder?

Only against one attack: breaking glass and reaching in to turn the thumbturn. Against kicks, prying, picking or drilling, the bolt, strike and frame decide the outcome, not the cylinder on the inside. If no glass sits within arm's reach of your lock, a good single-cylinder deadbolt with a reinforced strike is just as secure and safer to live with.

Where should I keep the key?

On a hook or spot near the door, within easy reach for someone leaving but out of reach from outside through a broken pane. Everyone in the household should know it, including older kids. Don't leave it in the lock out of habit, since that lets a reaching hand turn it. Rehearse the exit in the dark once a year.

Can you replace my existing double cylinder with a single cylinder?

Yes. The bores are the same, so we remove the double cylinder, install a single-cylinder deadbolt with a thumbturn inside and key it to your house key if you like. It's a quick swap. We can also strengthen the strike and talk about protecting the glass so you aren't trading security for safety.

Can it be keyed to match my other locks?

Yes, if it's the same brand and keyway, such as Kwikset KW1 or Schlage SC1. We pin both cylinders to your existing key, so one key opens everything. If your locks are different brands, we can match the new lock to one of them or rekey the others to a single key.

How far is Charter Oak from your base?

Charter Oak is about 38 miles from our San Bernardino base, roughly 43 minutes in light traffic. Arrival time depends on traffic and on the job the technician is finishing, so we give you an estimate on the phone before you commit.

Double Cylinder Deadbolt Installation in nearby cities

Call now(951) 903-3193

Daily 6:30am–11:30pm