Detached Garages & Accessory Structures


The following are required to construct a detached garage:

  • Check with the Planning and Zoning Department concerning location, setbacks, and lot coverage limits.
  • Check with utility companies for location of buried or overhead utilities and regulations (gas, sewer, water, electricity, cable television, and phone).
  • The Building Department suggests that the property be surveyed to establish lot lines.
  • Apply for required building, electrical, plumbing, and demolition permits prior to starting work from the Building Department. A site plan must be submitted which contains the following:
    • Address of proposed construction
    • Location and dimensions of existing buildings
    • Location of new construction or demolition
    • Lot dimensions (in feet)
    • Property owner
    • Relationship of adjacent streets, alleys, and easements to proposed new construction
  • The required side yard setback is three feet from property line. For corner lots, check with the Planning Department.
  • The required rear yard setback is five feet from the alley right of way. Check with the Planning Department for more information.
  • Garage walls, which face or are adjacent to other buildings within 10 feet, must be covered with 5/8 Type X sheet rock to the roof rafters or peak of the roof.
  • Residential garages are limited to 1,000 square feet maximum, and height of one story (15 feet to the peak of the roof).
  • Any garage over 1,000 square feet shall have frost footings of 42 inches depth, under 1,000 feet can be of floating slab construction. Note: Garage slab shall be at least four inches thick with the exterior 12 inches of slab at least six inches thick (must be reinforced with metal).
  • One-half-inch anchor bolts are required minimum four feet spacing and must meet 90 miles per hour (mph) wind loads.
  • Sill plates against construction slab must be of approved treated lumber.
  • Garage door headers shall be two two-inch by 12-inch headers for a 16-foot door span or its equivalent. Spans over 16 feet require stronger headers.
  • Garage wall studs shall be two inches by four inches, spaced 24 inches or less on center. If 24 inches on center rafters, must land vertically on wall studs.
  • Roof rafters must have a minimum of 30 pounds per square feet ground snow load and 90 mph wind load
    • Designed in accordance with the 2006 International Building Code Rafter Span Table 802.5.1(3)
    • Engineered truss rafters may be substituted
  • Corner bracing can be constructed of plywood sheathing, four-foot by eight-foot in size, one-inch by four-inch let-in bracing or approved metal strapping.
  • All electrical wiring shall be installed per the National Electrical Code and the City of Fort Madison Electrical Code. Electrical outlets shall be ground fault interrupter protected.
  • An electrical permit shall be obtained by the electrical contractor (or homeowner, if he qualifies), and an electrical inspection is required.
  • Driveway curb cut permits shall be obtained from the Public Works Department.
  • Roof and driveway drainage shall not be directed to adjoining properties.