Lock Installation: Choosing, Fitting and Keying New Door Hardware

What Lock Installation Covers

Lock installation is the work of fitting new hardware into a door and its frame so the lock operates exactly as its maker intended. That sounds obvious, yet a lock working precisely as designed is less common than you might expect. Plenty of locksets go in with a cordless drill and the paper template from the box. Most of them function. A good number also latch inconsistently, need the door shoved before the deadbolt will turn, or hang on screws that grab nothing but a thin strip of jamb.

Installation is different from two related services. Rekeying keeps your hardware and changes only the pins, so a new key works and old ones don't. Replacement swaps a worn or broken lock for a similar one that fits the holes already in the door. Installation is the broader category, and it includes:

• Preparing blank doors that have never held hardware
• Changing from one style of lock to another, such as a knob to a handleset or a mortise lock to a cylindrical set
• Adding a deadbolt, a secondary lock or flush bolts where none existed
• Upgrading builder-grade hardware to Grade 2 or Grade 1
• Outfitting a commercial space with the right lock function on every door
• Correcting earlier installs that were never quite right

Every one of those jobs follows the same sequence: measure, choose, prepare the door, set the strike, mount and adjust, key, and test. Listing the steps is easy. Doing each one precisely is what separates a lock that runs smoothly for a decade from one that starts sticking before the next rainy season.

The Measurements That Decide What Fits

Before we recommend any hardware, the door gets measured. A handful of numbers determine what will fit cleanly:

• Door thickness. Interior doors are commonly 1-3/8 inch and exterior doors 1-3/4 inch. Typical residential locks adjust across that range, while 2 inch and 2-1/4 inch doors need thick-door kits or hardware made for them.
• Backset. Measured from the door edge to the center of the cross bore, it is 2-3/8 inch on many houses and 2-3/4 inch on most commercial doors and many newer entries. Some decorative and mortise locks use other backsets entirely.
• Cross bore. The modern standard is 2-1/8 inch. Some older doors have smaller holes, and very old doors may have none because they were built for mortise hardware.
• Edge bore. Usually 1 inch for a latch or deadbolt. Some drive-in latches use a round face that needs no faceplate mortise at all.
• Spacing. On doors that carry both a lockset and a deadbolt, the distance between the two bores matters for handlesets and many decorative trims. A spacing of 5-1/2 inches center to center is common, but handleset designs vary.

Height matters too. Residential locksets usually sit somewhere around 36 inches from the floor to the center of the bore, and matching the neighboring doors looks better than drilling to a textbook figure. We also check the reveal, meaning the gap between door and frame along the latch side, because the strike has to be set for the door as it actually hangs, sag included.

Collecting these numbers before shopping prevents the most common installation headache: hardware that is perfectly good, just not made for this particular door.

Lock Types: Tubular, Cylindrical, Mortise and Specialty

Door locks fall into a few construction families, and each installs differently.

Tubular locks are the familiar residential knobs and levers. A latch tube slides in from the edge, the chassis passes through the cross bore and hooks into the latch, and two screws pull the trim together. Most Kwikset and Schlage residential hardware works this way. They're quick to install and easy to service.

Cylindrical locks look similar from the outside but use a heavier chassis designed for commercial traffic. Models such as the Schlage ND series and Sargent 10 Line use through-bolted trim, stronger springs to support lever weight, and latches built for steel frames. They're the standard Grade 1 choice for offices, schools and clinics.

Mortise locks put the latch, deadbolt and often several functions into one steel case that sits in a deep rectangular pocket in the door edge. Commercial examples include the Schlage L9000, Sargent 8200 and Corbin Russwin ML2000 lines, and decorative residential mortise sets are common on high-end homes. The pocket has to be cut accurately with a mortising jig, and the case must be handed to the door.

Specialty types cover the rest of what we install:

• Narrow-stile deadlocks and latches for aluminum storefront doors, typically Adams Rite style with a pivoting hookbolt
• Rim locks and rim cylinders that mount on the inside face of the door, including the cylinders that operate exit devices such as Von Duprin hardware
• Multipoint locks on modern patio and entry doors, which drive bolts or hooks at several points along the edge
• Flush bolts and surface bolts that secure the inactive leaf of a double door

Knowing which family a door uses tells us immediately what tools, templates and parts the job will need.

Lock Functions, and Why the Wrong One Causes Trouble

Function describes what a lock does from each side of the door. Choosing it is as important as choosing the brand, and on commercial jobs it's where expensive mistakes happen.

The common residential functions are simple:

• Passage. Latches but never locks, used on hallways and closets
• Privacy. Locks with a button or turn inside and opens from outside with a small emergency tool, used on bathrooms and bedrooms
• Entry. Keyed outside, push-button or turn-button inside, used on exterior doors alongside a deadbolt
• Dummy. A fixed handle with no latch, used on pantry pairs and closet doubles

Commercial hardware adds more choices:

• Office or entry. Locked or unlocked by a button or key, convenient for private offices
• Storeroom. Always locked from outside, always free from inside, so the door relocks every time it closes
• Classroom. Locked or unlocked from outside with a key
• Classroom security or intruder function. Lockable from inside with a key or indicator, so occupants never step into a hallway to secure the door

Put a storeroom lock on a private office and the occupant gets locked out every time a breeze closes the door. Put an office lock on a supply room and sooner or later someone leaves it unlocked overnight. On deadbolts, the choice between single cylinder and double cylinder matters for safety, because a door that needs a key from inside can slow an exit during a fire.

We match function to how each door is used, then confirm the function code on the packaging before anything goes on the door. Swapping a commercial function after installation sometimes means reordering an entire lockset.

Grades and Ratings: What BHMA Testing Tells You

The Builders Hardware Manufacturers Association publishes the ANSI/BHMA standards that most door hardware is tested against. Bored and cylindrical locks are covered by A156.2, and mortise locks by A156.13. Within those standards, products earn Grade 1, Grade 2 or Grade 3 based on operating cycles, strength against forcing, and other performance tests.

In practical terms:

• Grade 3 is light residential hardware. It suits interior doors and low-traffic spots.
• Grade 2 is heavier residential and light commercial hardware. It's the sensible floor for exterior doors on a home.
• Grade 1 is the top commercial grade, built for doors that open hundreds of times a day and absorb abuse.

Some residential packaging also shows a three-letter rating covering security, durability and finish, where A is the highest mark in each category. That label is useful because it separates finish quality, which matters a lot in Southern California sun, from mechanical strength.

Grades have limits worth understanding. A rating describes the lock as tested in a properly prepared door with its intended strike. Mount a Grade 1 deadbolt in a jamb held by short screws and the weak point simply moves from the lock to the frame. Pick resistance and key control aren't really what the common grades measure either; those come from high-security cylinders with restricted keyways.

Our advice is straightforward. Choose Grade 2 or better for any exterior door, Grade 1 for commercial doors and any home door that takes heavy use, and spend the remaining budget on a proper strike, long screws and accurate installation rather than on a finish upgrade alone.

Choosing a Brand Without the Sales Pitch

We install hardware from many manufacturers, and no single brand is right for every door. Here's how the familiar names tend to fit.

Kwikset is everywhere in Southern California tract housing. Its SmartKey cylinders can be rekeyed with a tool in seconds, which landlords appreciate, and the product range runs from budget knobs to well-built Grade 2 and smart deadbolts. Keys use Kwikset's own keyway, so they won't work in Schlage locks.

Schlage covers both homes and businesses. Residential lines include long-standing deadbolts such as the B60 series, and the commercial ND cylindrical and L9000 mortise families are common in offices and schools. Schlage residential cylinders accept a wide range of keys and rekey with standard pinning.

Yale offers residential smart locks such as the Assure line along with commercial cylindrical and mortise hardware. Baldwin sits at the decorative end, with forged brass trim and mortise entry sets favored on custom homes.

For commercial and specialty work, Sargent and Corbin Russwin build heavy cylindrical and mortise locks, Adams Rite dominates narrow-stile storefront doors, and Von Duprin is the familiar name in exit devices. Medeco, Mul-T-Lock and ASSA Abloy make high-security cylinders with restricted keys that can't be copied at a hardware counter; those products are sold through authorized channels and can carry lead times.

The practical rule: choose one brand for all the exterior doors so they can share a key, match the grade to the door's use, and pick a finish that will survive the exposure it faces. We'll tell you honestly when a less expensive option will do the job just as well.

Preparing the Door: Material by Material

Door prep is where an installation is won or lost, and each door material asks for a different approach.

Solid wood and solid-core doors are the most forgiving. We clamp a boring jig, run the hole saw halfway through from one face and finish from the other so neither side splinters, then drill the edge bore square to the face. Old fir and redwood doors can hide nails, filler or brittle grain near the edge, so the bit goes slowly there. Freshly cut wood gets a coat of sealer or paint, because bare end grain in a bore soaks up moisture and swells.

Hollow-core interior doors have a solid lock block glued inside the skin at the handle height, sometimes on only one side. If the bore misses that block, the lock clamps onto thin veneer and loosens within weeks. We locate the block before drilling and choose the side accordingly.

Fiberglass doors use a foam core under a thin molded skin, usually with a wood or composite edge. Sharp saws, low speed and light pressure prevent chipping. Many manufacturers prefer that the door be bored with their recommended templates, and we follow them.

Residential steel doors have an insulated core with a reinforced lock area. Commercial hollow-metal doors are usually prepped at the factory for a specific lock, often the standard cylindrical cutout commonly called a 161 prep, or for a particular mortise case. Matching the hardware to that prep is far better than field-cutting steel.

Aluminum storefront doors have narrow stiles with fixed pockets for deadlocks and latches. Backsets there are short and specific, so the lock body must match the stile exactly. When a door has been cut for something odd, we look for a lock that fits the existing pocket before suggesting any new cutting.

The Strike Side: Where Installation Quality Shows

The strike is the steel plate on the jamb that receives the latch and bolt. It's small and inexpensive, and it decides a great deal of how a door performs.

Start with the deadbolt. Its pocket in the jamb has to be drilled deep enough for the bolt to extend fully. A bolt that bottoms out partway leaves the lock technically locked but holding with less steel than it was built to use. A strike box, the metal cup behind the plate, keeps the pocket clean and stops wood from crumbling into the hole over time.

Then the screws. Jambs are typically thin boards attached to framing studs with a small gap between them. Screws around three-quarters of an inch long only hold the jamb itself. Screws long enough to pass through the jamb and the shim space into the stud behind it change the outcome of a kick dramatically, because the force has to break framing instead of a strip of trim. We add the same treatment to at least one screw in each hinge, so the hinge side doesn't become the new weak point.

The latch needs attention as well. Most entry latches include a small auxiliary plunger beside the main latch. When the door closes, the strike presses that plunger in, which deadlocks the latch so it can't be pushed back with a card. If the strike opening is too wide or the door gap too large, the plunger slips into the opening and the deadlocking feature does nothing. We set the strike so the plunger rests on the plate.

Finally, alignment. A door that has sagged should be corrected at the hinges, with longer screws or shims, rather than by filing the strike opening oversized. Fix the cause, then set the strike.

Keying a New Installation So One Key Does the Work

Every new lock comes with keys, and unless it was ordered keyed alike, every box has a different set. Install four locks straight from the packaging and you'll carry four keys. Planning the keying is part of a good installation.

The options are straightforward:

• Keyed alike. Every lock on the property opens with the same key, the usual choice for houses
• Keyed to existing. New cylinders are pinned to match a key you already carry, possible when the keyway is compatible
• Keyed separately with an owner key. Each unit, office or room has its own key, and a master key opens all of them

Keyways are the limiting factor. A Kwikset key won't enter a Schlage cylinder and vice versa, because the profile of the blade is different. When a home mixes brands, we either standardize the exterior doors on one brand or key each brand separately and explain the tradeoff. High-security systems use patented or restricted keyways, which means duplicates come only through an authorized source with the owner's approval.

We usually re-pin cylinders before they go on the door, which keeps the process tidy. If you change your mind on-site, rekeying an installed cylinder is still quick for most residential hardware.

One honest note about key control: a stamp reading do not duplicate discourages casual copying, but it isn't a legal barrier and some shops ignore it. If controlling copies truly matters, a restricted keyway is the real solution, and we can explain how those systems work before you commit.

Commercial Doors: Fire Labels, Egress and Accessibility

Commercial installations come with rules that residential work rarely touches, and ignoring them can fail an inspection or create a real hazard.

Fire-rated doors carry a label, usually on the hinge edge of the door and in the frame's hinge jamb. Hardware on a rated opening generally has to be listed for that use, the door must latch positively every time it closes, and field modifications are tightly limited. Drilling extra holes or adding unlisted hardware can compromise the rating. When a rated door needs a different lock prep, the correct answer is sometimes listed conversion hardware and sometimes a different door.

Egress rules say that doors along an exit path must open from the inside without a key, a tool or special knowledge. That's why storeroom locks free from inside, why exit devices exist, and why a deadbolt requiring a key from inside is a problem on many commercial doors. Some occupancies permit key-operated locking on the main entrance under specific conditions, such as required signage, and we follow what the local fire authority has approved for your building rather than guessing.

Accessibility requirements in California's building code favor hardware that a person can operate with one hand, without tight grasping, pinching or twisting the wrist, mounted within a set height range. In practice that means levers or push-pull hardware on public-facing doors.

Electrified hardware brings another layer. Electric strikes and electrified locks are specified as fail-safe, unlocking when power drops, or fail-secure, staying locked when power drops, and the choice depends on the door's role in egress and fire protection. Wiring them into an access control panel can involve a licensed low-voltage contractor, and we'll say so when a project reaches that point.

California Details That Shape Residential Installs

A few state rules and regional conditions influence how we install locks on homes and rentals.

Rental property comes first. California Civil Code 1941.3 requires landlords to provide a deadbolt on each main swinging entry door of a dwelling unit, along with window security and locking devices on certain doors. The statute expects the bolt, when locked, to extend at least 13/16 of an inch beyond the strike edge of the door into the jamb. Civil Code 1941.5 and 1941.6 require a landlord to change the locks within 24 hours of a tenant's written request in certain situations involving a protective order or similar documentation.

Attached garages are another detail. The door between an attached garage and the living space is expected to be solid or fire-resistant and to close and latch on its own. Adding a deadbolt to that door is fine, but disabling the self-closing hinges or swapping in a latch that won't catch undermines its purpose.

Exit safety matters inside the home too. Residential egress doors are meant to open from inside without a key, which is why we discuss single cylinder deadbolts as the default and explain the risks of double cylinder hardware before installing it.

Then there's the climate. Inland summers heat exterior doors enough that steel expands and wood dries out, winter storms swell the same doors, and Santa Ana winds slam them hard enough to loosen trim. Closer to the coast, salt air pits plated finishes. We set strikes for that seasonal movement and steer you toward finishes and materials that suit your exposure.

Lastly, HOAs. Many associations govern exterior hardware style and finish, so it's worth checking the guidelines before choosing a new front door set.

How Julian's Locksmith Handles Installations Across the Region

Julian's Locksmith is a mobile locksmith based in San Bernardino, and we bring installation work to you across the Inland Empire, the San Gabriel Valley, the Pomona Valley, north Orange County and southeast Los Angeles County. Our service van carries boring jigs, hole saws, mortise templates, chisels, strike boxes, long screws, pinning kits and a working stock of common hardware, so many jobs finish in one visit. Specialty commercial and high-security products are ordered after we confirm the door details.

Here's how an installation typically goes:

• You call (951) 903-3193 and describe the doors, or text photos of the door edge, lock face and strike
• We discuss hardware options and give you a quote before ordering or cutting anything
• On arrival, we verify your identity and your authority over the property, such as ownership documents or the owner's written approval
• We prep, install, key and test each door, then walk you through how everything works

Our hours are 6:30 a.m. to 11:30 p.m., seven days a week. We're open weekends too. Installations are scheduled work, and we give you an honest arrival window when we book.

We're licensed by California's Bureau of Security and Investigative Services under locksmith company license LCO7891, which you can confirm at search.dca.ca.gov. The Locksmith Act in the Business and Professions Code governs how locksmiths operate in the state.

And we'll be candid about limits. If your frame needs a carpenter, your fire door needs listed hardware, or your access control wiring needs a low-voltage contractor, you'll hear that from us before the job starts rather than after.