At UAP we supply internal door locks for doors in houses, flats, offices and rented homes. The range moves from plain latches through to keyed mortice cases. Every item ships with the fixings a joiner needs on site.
Internal door locks hold a door closed and release it the moment someone works the handle. Everything else follows from that one job. A latch bolt keeps the door sitting in its frame. A deadbolt adds a second bolt that only a key or a thumbturn can move. Interior door locks therefore cover a wide span of duties, from a bedroom door that simply needs to stay shut to a store cupboard that has to stay locked.
The load on internal door locks differs from the load on a front door. Nobody attacks a bathroom door with a crowbar. The mechanism faces thousands of ordinary openings every year, so smooth action matters more than raw resistance. UAP builds its interior door locks around that reality. The cases stay light under the hand, yet the bolts throw cleanly for years.
Choosing well saves money later. A latch that sticks gets forced, and a forced latch wears out fast. Internal door locks from UAP arrive sized to standard UK door thicknesses, so the fit is right first time.
The UAP catalogue splits interior door locks into four working families, each answering a different need on the door:
Picking the right family takes one question: does this door need locking, or only closing? A landing door needs closing. A home office door with paperwork inside needs locking. Internal door locks in the UAP range answer both without you buying more mechanism than the door justifies.
Each family then divides by case size and by the shape of the forend. That second layer decides whether the new lock drops into an existing mortice or forces you to cut fresh timber. Interior door locks matching the old cut save an hour on every leaf.
Internal sash locks contain two bolts, while a deadlock contains one. The sashlock case holds a sprung latch bolt that the handle retracts, plus a deadbolt that a key throws. You get everyday use and locking from a single case cut into the door edge. A deadlock case gives you the deadbolt alone, so the door needs a separate latch or a pull handle beside it.
That difference points each product at a different door. Internal sash locks suit any room where people walk in and out all day, then lock the door at night. Deadlocks suit cupboards, risers and store rooms, where the door stays shut and nobody wants a handle sticking out into a corridor.
UAP supplies internal sash locks in three cylinder patterns, so the case matches whatever key system the building already runs:
Backsets of 65 mm and 75 mm cover both slim and deep door stiles. A joiner fitting a converted terrace often meets both on one floor, since older leaves carry wider stiles than factory doors. Ordering internal sash locks in both backsets prevents a second delivery.
Internal door privacy locks let someone lock a door from the inside without a key, then let someone else open it from outside in an emergency. A thumbturn on the room side throws the bolt. A slotted release on the corridor side takes a coin or a screwdriver. That pairing gives privacy during normal use and access when a child locks themselves in.
UAP bathroom locks come as a mortice case with a latch bolt and a privacy bolt together. The handle works the latch, the thumbturn works the bolt. Internal door privacy locks in this pattern need no cylinder, so nobody carries a key for the bathroom. The same case suits an en suite, a cloakroom, a changing room or a bedroom where an adult wants a door they can secure.
Heavy duty versions of these bathroom locks exist for doors that see constant traffic. A cloakroom in a busy office opens far more often than a family bathroom, and the mechanism has to keep pace. UAP also lists a mortice deadbolt for doors that already carry a latch. That option adds internal door privacy locks to an existing door without replacing the latch.
Fit the release the right way round. The thumbturn always faces the private side, the coin release always faces the corridor. Reversing them defeats the whole point of internal door privacy locks and creates a genuine hazard.
Three measurements decide whether internal door locks fit the door you already have. Take them from the old lock before you order, because guessing costs you a return.
Read the case size first. UAP quotes internal door locks by case size, so a 65 mm case and a 75 mm case tell you how deep the pocket goes. A slim stile takes the shorter case. A deep stile, common on Victorian doors and on wide fire doors, takes the longer one.
Then check the forend shape. A square forend has right angled corners, and a radius forend has rounded ones. The old mortice was cut to match one of them. Ordering the wrong shape means chiselling the pocket again or filling the corners, and neither looks tidy. UAP lists square and radius versions of its latches, sashlock cases and bathroom locks, so a like for like swap stays possible on most doors.
One warning about older properties. Some period doors carry backsets far deeper than anything modern, because the knob sat well clear of the jamb. Measure those doors individually rather than assuming the house matches.
The forend of a lock is visible ironmongery, so its finish belongs in your specification. Open any door and the metal strip along the edge shows plainly against the timber. Internal door locks finished in a different metal from the handles break the look of a room that has otherwise been carefully specified.
UAP finishes its interior door locks across the same palette used for its handles and escutcheons. Evershine Brass, satin stainless steel, polished stainless steel, bronze and matt black run through the range, with nickel plated and electro brassed options on selected cases. Choosing the lock finish at the same time as the handle finish keeps every door edge consistent from the hallway to the loft.
Finish choice also affects how the metal ages. Satin stainless steel hides fingerprints and handling marks, so it earns its place in family homes and busy offices. Polished finishes reward polishing, then show every mark in between. Matt black suits painted doors. Order the strike plate and the escutcheon in the same finish as the lock. Those parts sit centimetres apart on the frame, and a mismatch shows immediately.
Four groups of buyers work with the UAP range, and each one comes to internal door locks with a different question.
Homeowners and renovators want a door that closes properly and a bathroom that locks. They replace hardware door by door, so they need the measurements explained plainly and a finish matching what they already own. Interior door locks that drop into the existing mortice save a weekend of remedial joinery.
Joiners and door fabricators buy internal door locks in volume for hanging runs of doors. They care about consistent case sizes and about packs that arrive complete with strike plates, latch plates and fixing screws. Anything missing from the box costs them a trip.
Landlords and housing providers need internal door privacy locks that survive tenants and internal sash locks that secure meter cupboards and store rooms. Long service life beats decorative detail for them, and standard cylinder profiles let them key doors alike across a block.
Commercial fitters specify interior door locks for offices, clinics, schools and care homes. They need heavy duty cases for high traffic, plus finishes that survive constant handling. UAP supports all four groups from one catalogue, so a specification stays consistent across an entire building.
