Howard County, MD Building Safety: Fire Sprinkler Requirements (2026)

102 lists the local amendments the County Council layered onto that model code. 2, titled 'One- and two-family dwellings automatic fire sprinkler systems,' the IRC provision requiring an automatic sprinkler system in new one- and two-family homes. Howard County did not delete or weaken that mandate; it rewrote only the exception. The amended exception reads that after the first appearance of 'sprinkler system,' the rest of the sentence is deleted and replaced so that additions or alterations less than fifty percent of the existing gross area of all floors of the building or structure are exempt from fire sprinkler systems.

In practice, a homeowner adding a small addition, such as a single bedroom or a modest kitchen bump-out, that comes in under half of the home's existing total floor area does not have to retrofit sprinklers into the rest of the house to get a permit for that addition. A larger addition or a whole-house renovation that crosses the 50 percent threshold does not get that pass, and new one- and two-family construction is covered by the base sprinkler requirement without any local carve-out. 2 at the same time they review the rest of a residential building permit application.