Montgomery County, MD Building Safety: Carbon Monoxide Detectors (2026)
Key Facts
- Covers
- single-unit, two-unit, townhouse dwellings
- Applies to
- permits issued before Jan. 1, 2008
- Trigger
- fuel-burning appliance or attached garage
- Placement
- near bedrooms, every occupiable level
- Violation
- Class C violation
Summary
Owners of pre-2008 single-unit, two-unit, and townhouse dwellings with a fuel-burning appliance or attached garage must install carbon monoxide alarms near bedrooms and on every occupiable level.
(1) The owner of each occupied single-unit, two-unit, and townhouse dwelling unit containing a fuel burning appliance or attached garage must install carbon monoxide detection and warning equipment. (2) Carbon monoxide alarms or detectors must be installed as follows: (A) outside of each separate dwelling unit sleeping area and in the immediate vicinity of the bedrooms; and (B) on every occupiable level of a dwelling unit, including basements, excluding attics and crawl spaces.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: 2026 S-90: Montgomery County Code contains legislation effective through May 7, 2026 | Zoning Updated Effective: April 13, 2026 | COMCOR Regulations effective as of July 1, 2026).
Full Breakdown
Montgomery County Code § 26-8A requires the owner of each occupied single-unit, two-unit, and townhouse dwelling unit with a fuel-burning appliance or attached garage to install carbon monoxide detection and warning equipment, but the section applies only to units for which the building permit was issued before January 1, 2008 (newer construction is covered instead by the building code's fire-alarm requirements). Alarms must sit outside each dwelling unit's sleeping area and near the bedrooms, and on every occupiable level including basements, though attics and crawl spaces are excluded. Installation and maintenance must follow NFPA 720, and hard-wired or plug-in units need battery back-up. The Department of Housing and Community Affairs enforces the rule, including through a municipal agency in any incorporated municipality where this housing chapter applies.
Violations & Fines
The enforcing agency orders the owner to install a missing carbon monoxide alarm or detector under § 26-12; failing to comply with § 26-8A is a Class C violation notwithstanding the general penalty scale in § 26-16.
Frequently Asked Questions
Does this rule apply to a newly built house?
Is my unit exempt if it has no gas appliance or garage?
Sources & Official References
Other rules in Montgomery County
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