Accessory Structure Size and Development Standards in Concord
In Concord, the maximum floor area for accessory structures in residential districts is determined by the minimum lot size of the property, ranging from 480 square feet to 2,000 square feet. All accessory structures must be subordinate to the primary structure in size, height, and location, and are subject to specific setback and design requirements.
Maximum Floor Area for Accessory Structures
The Concord Development Code establishes specific maximum floor area limits for accessory structures located in rear yards within residential districts based on the minimum lot size [Section 18.200.030].
| Minimum Lot Size (Square Feet) | Maximum Floor Area for Accessory Structures in Rear Yards (Square Feet) |
|---|---|
| Less than 5,000 | To be specified in the subdivision or use permit approval |
| 6,000 | 480 |
| 8,000 | 560 |
| 10,000 | 800 |
| 12,000 | 800 |
| 15,000 | 800 |
| 20,000 | 1,000 |
| 40,000 | 2,000 |
An increase of up to 10 percent of the maximum floor area shown above may be allowed subject to approval of a minor exception [Section 18.200.030]. Additionally, accessory structures shall occupy no more than 25 percent of a required rear yard area [Section 18.200.030].
General Design and Development Standards
All accessory structures at single-family dwellings must comply with the following development standards:
- Subordination: Accessory structures shall be subordinate to the primary structure in terms of size, height, location, and appearance [Section 18.200.030].
- Location: Accessory structures are prohibited in the front and street-side yards and may not project beyond the front building line of the primary structure [Section 18.200.030].
- Separation: A minimum five-foot separation must be maintained between all structures on the site, including the primary structure and other accessory structures, except that patio covers and carports may be located immediately adjacent to the primary structure [Section 18.200.030].
- Design Compatibility: Roofing and siding materials, as well as the color scheme of the accessory structure, must match or be complementary to the primary dwelling [Section 18.200.030].
- Height and Setbacks: Accessory structures that meet the primary structure’s setback requirements may be up to 16 feet in height. Accessory structures between six and 12 feet in height must maintain a minimum five-foot side and rear setback. For these structures, height may be increased by one foot for every two feet of additional setback provided, up to a maximum height of 16 feet [Section 18.200.030].
Exceptions
The following structures are exempt from the standard setback requirements:
- Small Structures: Accessory structures less than 120 square feet in area, six feet or less in height, and not on a permanent foundation do not require a building permit and are not subject to these provisions [Section 18.200.030].
- Decks and Patios: Uncovered decks or patios 30 inches or less above existing grade shall be set back at least three feet from an interior side or rear property line [Section 18.200.030].
- Gazebos and Patio Covers: Gazebos or patio covers open on at least three sides and supported by individual footings that meet side yard setbacks may be located within three feet of the side or rear property line [Section 18.200.030].
Sections Cited
- Section 18.200.030 (Accessory structures)