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Accessory Structures

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77 PhotoAn accessory structure is any secondary building on a single family lot other than the main habitable building(s). Examples include workshops, storage sheds, detached private garages, guest houses, green houses, tool/garden sheds, playhouses, and animal shelters.

Accessory buildings may be attached to the main building or may be detached structures. If attached to the main building, the structure must comply with the same zoning ordinance and structural requirements as the main building.

Permits Required

A building permit is required if the accessory building is more than 120 sq. feet of floor area. Separate electrical or plumbing permits are required for electrical wiring or plumbing installed in the building.

Required Drawings

Three copies of the following information for buildings over 120 sq. feet submitted for a building permit must be drawn on substantial paper (18” x 24” minimum) drawn to a scale of ¼”=1’

  • Plot plan showing the position of the proposed project in relation to existing buildings, property lines, and public utility easements. This plan is to be drawn to a scale of 1:20, which means 1 inch is equal to 20 feet. A plot plan is required for buildings requiring Planning Department approval.

  • Foundation plan indicating the type of foundation and the size of footings used. A perimeter foundation is not required for buildings less than 400 sq. feet.

  • Framing section showing sizes of framing members and the method if assembly.

  • Floor plan showing detailed location of the walls, supports, size and location of the doors, windows, electrical outlets, plumbing fixtures, and the square footage of the project.

  • Elevations showing all exterior sides of the proposed structure.

Additional Required Information

  • Description of the work.
  • Location of the project (street name and number).
  • Legal owner’s name, address and phone number.
  • Valuation of the proposed work.
  • Other information as may be required.

The owner, an authorized agent, or a licensed contractor is the only person who can legally sign for the building permit. Upon issuance of the permit, the holder of the permit has 180 days (6 months) to commence work on the project.


The following inspections are required for accessory buildings for which a permit has been issued.

  • Foundation: To be made after footings are excavated, forms erected and reinforcing steel is in place.

  • Roof Nailing: To be made after the installation and nailing of the roof sheathing.

  • Frame: To be made after the framing, fire blocking, siding, lath and braced panels are in place and all vents, rough electrical and plumbing are installed.

  • Final: To be made when the building is finished.

If it is unclear as to what inspections pertain to your project, contact the Building Division.