In detail: Rim locks

Door hardware is often considered part of the jewelry of the house. Many people consider the finish or shape of the knob when selecting door hardware, but often overlook approaching the hardware selection from a historical outlook. The selection of a period specific hardware set can add a key detail to a home that is built in a historically inflected design language, or properly complete the restoration of a historic structure.

Rim lock door hardware, also known as box locks, were largely manufactured in the British Isles from the colonial period through the victorian period. Rim locks were prevalent in early american residential architecture and were almost always imported from England. The colonies produced raw materials and shipped them to England, and manufactured goods were returned. As independence was gained and manufacturing increased in the States, the hardware was produced on this side of the Atlantic.

Above: Rim locks are still reproduced. This set has an iron box with solid brass components and porcelain knobs. We used this hardware in a new construction residence that was built in the Greek Revival style. A few manufacturers have boxes with the keys permanently mounted so that they don't get misplaced.

Early rim locks were typically iron followed by brass. Early knobs were also iron, but porcelain, clay, and brass knobs became common at later dates. Glass knobs were introduced in the victorian period as well as more intricate box designs.

Rim locks are still manufactured today for use in historic restorations as well as in new construction to gain an authentic period look. Rim locks operate differently than most modern door hardware and thus have a different feel during operation. This creates an impression on the user and contributes to the ambiance of the architecture.

Above: Brass horizontal rim lock that we used on a modern renovation of an 1850's masonry Charleston single house in Charleston's landmark historic district.

It should be noted that rim locks may be used on exterior doors, but should always have a secondary form of protection to prevent intrusion. Deadbolts, flush bolts, or surface bolts are commonly used to provide greater security in exterior door applications. In new construction, the door jamb may need special attention regarding the location and mounting of the rim lock (the catch box in particular) depending on the door swing.