Door Knob Lock Replacement

A failing knob lock sends clear signals: the latch retracts sluggishly, the cylinder wobbles, keys start feeling gritty, or the whole assembly rattles against the door face. What looks like a simple swap is complicated by Toronto's housing stock. A prewar detached in Rosedale often has a door edge cut for an antique mortise lock cartridge, while a 1960s North York semi may have a non-standard backset that modern knob sets don't fit without boring the door. A rushed replacement with the wrong backset measurement leaves gaps around the strike plate — gaps that compromise both security and weather sealing on exterior doors.

Interior doors present their own variables. A door knob with lock for a bedroom or bathroom needs privacy function hardware, not keyed entry hardware, and the spindle length has to match the door thickness. Get either wrong and the turn button won't engage the latch fully, or the knob will bind under load. Our technicians measure before ordering, confirm the door prep dimensions, and adjust the strike plate mortise in the jamb so the latch engages cleanly — no rattle, no sticky throw.

Many Toronto homes — particularly those built before 1960 in neighbourhoods like Cabbagetown, Riverdale, or Forest Hill — were originally fitted with a mortise lock rather than a bored cylindrical knob set. A mortise lock lives inside a deep rectangular pocket cut into the door edge and combines a deadbolt, a latch bolt, and sometimes a privacy or key function in a single steel case. It is significantly stronger than a standard knob lock because the lock body is embedded in the door rather than surface-mounted, and the strike plate engages across a much wider area of the jamb.

When a mortise lock cylinder wears out or the internal cam breaks, replacing just the cylinder is often the right call — pulling the entire door edge apart for a new bored knob set would mean patching a large mortise pocket and potentially weakening the door. Our team works as a specialist locksmith — mortise lock service is a core part of what we do — so we carry replacement cylinders, cam sets, and full mortise cases to handle both repairs and full swaps. If you're upgrading from an old knob lock to a mortise lock for better security, we handle the door preparation, hardware installation, and key cutting in the same appointment.

Exterior door knob lock hardware faces a far harder life than interior hardware: UV exposure, Toronto's freeze-thaw cycles, salt spray from winter road clearing, and the mechanical stress of thousands of entries per year. A door knob with lock and key on a front or back exterior door should be rated ANSI/BHMA Grade 1 or Grade 2 at minimum. Many builders-grade knob sets installed on condos and rental units along Yonge Street or Sheppard Avenue are Grade 3, which is fine for interior use but wears quickly on an exterior door used multiple times daily.

For commercial properties — a retail unit, a multi-tenant office, or a shared building entrance — a double lock door knob or a knob-and-deadbolt combination often isn't enough. A commercial locksmith assessment frequently points toward a heavy-duty mortise lock with a restricted key system, giving building managers control over who can duplicate keys. Our commercial locksmith services include master key planning, high-security cylinder upgrades, and coordination with building management so the replacement fits the overall access control strategy. If you're not sure what grade or function your door needs, call (437) 476-0564 — we assess, advise, and confirm an exact up-front price before any work begins.

Locked out at midnight in Don Mills because a knob lock cylinder finally gave out? That's exactly the situation our emergency locksmith service is built for. We operate 24/7 — every hour of every day, including holidays — and our mobile units are dispatched from across the Toronto area to keep response times practical. Ownership verification is a standard step before any lock work begins, which protects every legitimate property owner and tenant we serve.

Pricing for door knob lock replacement depends on several honest factors: the type of hardware selected (a basic privacy knob differs in cost from a Grade 1 keyed knob set or a full mortise lock case), whether the work is happening at 2 p.m. on a weekday or 2 a.m. on a Sunday, the travel distance to your address, and whether any door preparation work — strike plate adjustment, bore enlargement, or jamb repair — is needed. We confirm every figure before touching the door. There are no surprise line items added after the job. Our goal is a damage-free replacement where existing door and frame material is preserved; if a bore or mortise adjustment is unavoidable, we explain it clearly in advance.

North York Heritage Lock & Key covers a broad scope of hardware and security work beyond knob replacement. Our services include: residential knob lock replacement (interior and exterior), mortise lock installation and cylinder replacement, deadbolt installation and re-keying, keypad and smart lock conversion, high-security cylinder upgrades (Medeco, Mul-T-Lock, Schlage B-series), master key system design and implementation, commercial locksmith door hardware assessment, panic bar and exit device installation, lock-out service for residential and commercial properties, mailbox lock replacement, garage door lock service, sliding door lock replacement and patio door lock upgrades, cabinet lock installation, padlock and hasp replacement, key duplication and restricted key cutting, broken key extraction, lock repair without full replacement where possible, door closer adjustment, strike plate reinforcement and security plate installation, hinge bolt installation, access control system consultation, intercom lock cylinder service, storage unit lock changes, safe lock service and combination changes, and full re-key service after a move, renovation, or lost-key situation. If your specific need isn't listed, call us — our team's experience covers the full breadth of door and lock hardware found across Toronto's diverse housing and commercial stock.