Anne Arundel County, MD Building Safety: Fire Sprinkler Requirements (2026)
Key Facts
- Applies to
- new one- and two-family dwellings
- Design standard
- NFPA 13D
- Renovation trigger
- >50% habitable-area increase
- Enforced by
- Dept. of Inspections and Permits
- Base code
- IRC § R313.2, locally amended
Summary
Anne Arundel County's amended IRC section R313.2 requires an automatic residential fire sprinkler system, installed to NFPA 13D, in every new one- and two-family dwelling, and extends that mandate to existing homes undergoing additions or alterations that grow habitable space by more than 50 percent.
In section R313.2, after "Dwellings" at the end of the first sentence, insert "and in existing one- and two-family dwellings where any construction, alteration, enlargement, replacement, or repair constitutes an increase in habitable square footage, which exceeds 50% of the existing habitable square footage, including bathrooms, closets, hallways, storage spaces and utility spaces. If an existing structure is currently suppressed, any addition, alteration, enlargement, or replacement to the existing structure must be suppressed in accordance with R313.2.1."
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: 2026 S-93: County Code is current through May, 2026).
Full Breakdown
The 2021 IRC, as locally amended by Anne Arundel County Code § 15-2-102 and its incorporated Supplement, keeps the code's rule that new one- and two-family dwellings get an automatic residential fire sprinkler system, and extends that duty to existing homes: any addition, alteration, enlargement, replacement, or repair that grows habitable square footage by more than 50% must also be sprinklered, per IRC § R313.2.1. Systems must follow NFPA 13D design and installation standards. The Department of Inspections and Permits enforces this countywide, including unincorporated Glen Burnie and Severna Park; Annapolis and Highland Beach use their own city codes.
Violations & Fines
Skipping the required system, or crossing the 50%-habitable-area renovation threshold without one, holds up the building permit and certificate of occupancy; the Department of Inspections and Permits can also issue a stop-work order under County Code § 15-5-104.
Frequently Asked Questions
Do all new houses in Anne Arundel County need fire sprinklers?
Does remodeling my existing house trigger the sprinkler requirement?
Sources & Official References
Other rules in Anne Arundel County
Compare Anne Arundel County to another location·View the Maryland building safety overview
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