Lincoln County, SD Fire Regulations: Smoke Detectors (2026)

Section R314.3 of the International Residential Code, adopted for Lincoln County at § 151.33, sets five location rules for smoke alarms: inside every sleeping room; outside each separate sleeping area in the immediate vicinity of the bedrooms; on every additional story of the dwelling, including basements and habitable attics but not crawl spaces or uninhabitable attics; not less than 3 feet horizontally from the door or opening of a bathroom containing a bathtub or shower, unless that placement would prevent required coverage; and in both the hallway and the adjoining room whenever an open room's ceiling is 24 inches or more taller than the hallway ceiling serving a bedroom, though hallways under 4 feet long are excused from that last rule.

A split-level home without an intervening door between adjacent levels can satisfy the upper level's coverage with a single alarm as long as the lower level sits less than one full story below. R314.4 then requires interconnection: once any dwelling unit needs more than one alarm under R314.3, activating one alarm must sound every alarm in the unit, though listed wireless interconnected alarms satisfy this without hard-wiring, and existing-area retrofits are excused from adding interconnection unless wall or ceiling finishes are already being removed or an attic, crawl space, or basement gives easy access.