The old lock is coming off, and the new one has to suit the door as it is. Start with the body type. Mortise, cylindrical, tubular and rim locks are built differently, and makers price them as separate lines: the Accentra price book, for example, has its own sections for mortise locks, cylindrical locks, tubular lever locks and auxiliary locks, where its rim locks appear.
Which lock fits my door prep?
The door edge gives the first answer. A mortise lock shows a long front plate there, 1-1/4 by 8 inches on the Marks USA 5 Series lock body. A cylindrical or tubular lockset shows only a short latch front, 1 or 1-1/8 by 2-1/4 inches on Marks USA models. A rim lock is fastened to the surface of the door instead of being set into it.
Door preparation has standards of its own: BEST's catalogs refer to ANSI A115.1 for the 40H mortise lock and A115.2 for the 9K cylindrical lock, and the maker's template for your lock gives the exact cutouts.
Mortise locks
A mortise lock is built around a lock body, the case that fits into a cutout in the door edge. In the Accentra price book an 8800 Series lock body comes with its armor front and strike, while the trim is priced separately and the cylinder is ordered on its own. BHMA's standard for mortise locks is ANSI/BHMA A156.13, cited in BEST's 40H catalog and on Marks USA's mortise lock page.
When only the body has failed, our guide to replacing a Schlage L9000 lock body covers function, hand and trim, and the Sargent 8200 templates guide matches each lock to its document. Mortise cylinders and their cams have their own guides for Schlage and GMS.
Cylindrical locks (bored locks)
A cylindrical lock is built on a chassis that fits a round hole bored through the door. BHMA's standard for bored and preassembled locks and latches is ANSI/BHMA A156.2, and both Schlage's ND Series service manual and BEST's 9K catalog cite it. Residential locksets have a BHMA standard of their own, A156.39.
Our guides to Schlage, Sargent and Yale and ACCENTRA model numbers decode the cylindrical and mortise lines of those makers. For residential doors, our guide to bore, backset and door thickness covers Schlage and Emtek locks.
Tubular locks
A tubular lock also goes into bored holes, and its latch front may be the same size as a cylindrical lock's. Schlage keeps the two apart, calling its ND Series a cylindrical lock and its LT Series a tubular lock. In the Marks USA and Accentra price books the tubular lockset sections list passage, privacy, communicating and dummy functions. Marks gives its tubular locksets a standard door thickness of 1-3/8 to 1-3/4 inches, against 1-5/8 to 1-7/8 inches for cylindrical locksets and 1-3/4 inches for mortise. Its Series 1 tubular locksets are listed in keyless and dummy trim functions, while its 10 Line cylindrical knobsets also come in keyed functions such as classroom F84 and storeroom F86.
A product name can mislead. Schlage's ND manual lists TLR as the Tubular lever design, so an ND lock with that lever is still a cylindrical lock. Codes such as F75 passage and F76 privacy are explained in our lock functions guide.
Rim locks
Medeco's current catalog lists surface mounted deadbolts, night latches, panic devices and jimmy-proof locks, also known as vertical dropbolts, as examples of the auxiliary devices a rim cylinder is used with. Accentra files its rim locks under auxiliary locks, among them the 112 heavy-duty deadbolt and the 197 jimmy-proof deadlock, and BHMA's standard for auxiliary locks is ANSI/BHMA A156.36.
Rim exit devices are covered in our exit device types guide. Rim cylinders are in the Schlage and GMS cylinder guides above, and the 112 and 197 numbers in our Yale and ACCENTRA guide.
Fire-rated and electrified versions
Marks USA's mortise page lists a UL 3-hour fire rating for its Series 4, 5, 5PD and 5SS50 mortise locks with 3/4 inch latch bolts, on doors up to the sizes the page states, and Accentra offers the rating on its RL201, RL202 and RL228 tubular locks when the F suffix is added. Accentra's price book also has electrified sections for both mortise and cylindrical locks. Our electrified door hardware guide explains fail safe and fail secure.
Browse mortise locks, cylindrical and tubular locks and gate, rim and specialty locks on our store. If the door also takes a deadbolt, see our deadbolt guide.
If the old lock carries markings you cannot place, send them to us before you order. Our customer support team is available Monday - Friday, 8 AM - 4 PM Central Time, at 1-888-800-7789 or [email protected].
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