Rev 10.5.17

For attached or detached buildings on a residential lot

No separation is required between residential structures when located on the same parcel.
Residential structures with less than six (6) feet between them, if not protected from the assumed property line as required by code, and with a combined square footage of 3,600 square feet or more, will require a Fire Marshal review.

Detached or attached garages separated less than six (6) feet apart, shall be protected from any residential wall not perpendicular to the garage wall by not less than 1/2 inch gypsum wallboard applied to the garage side. Habitable rooms above shall be separated by not less than 5/8 inch Type X gypsum wall board. Where the separation is a floor-ceiling assembly the walls supporting the separation shall be protected on the garage side by not less than 1/2 gypsum wallboard. Openings other than doors are not allowed with separation distance less than 6 feet. Openings for doors in walls not perpendicular, with less than six (6) foot of separation distance, shall be protected by a solid wood door not less than 1 3/8 inch in thickness, solid or honeycomb steel doors not less than 1 3/8 inches thick, or 20-minute fire-rated doors. Garages from 1,000 square feet to 3,000 square feet require an eight (8) foot fire separation distance between the garage and residence.

Attached enclosed breezeways shall be protected on the garage side with not less than 1/2 inch gypsum wall board, sealing off the enclosed area in line with the garage wall. Open breezeways with no concealed spaces need not be protected. Carports not open on at least two sides shall be considered garages and shall comply with the provisions for garages.

A residential garage is limited to 3,000 square feet which is classified as a U occupancy by the building code. When the garage is over 3,000 square feet it must be classified as a different occupancy and meet the commercial fire flow requirements per the Fire Code. A garage can be divided into areas less than 3,000 square feet by installing a two-hour fire wall and be considered two separate buildings.

Fire separation distance (distance from structure to property line) for a garage of 1,000 square feet or less is three (3) feet. Garages of 1,000 square feet to 3,000 square feet require a five (5) foot separation distance.

Fire separation distance for a residence is three (3) feet. No openings are allowed for any exterior wall within the required separation distance. Exterior walls within the fire separation distance shall have not less than one hour fire resistive rating with exposure from both sides. Projections shall not extend to a point closer than two (2) feet from the property line. Detached garages accessory to a dwelling, less than three (3) feet from the property line, may have roof eave overhangs not exceeding four (4)inches into the two (2) foot setback. Projections shall not extend over the lot line. Projections extending into the fire separation distance shall not have less than one-hour fire-resistive construction on the underside.