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BCG 96-11: Cargo Containers
QUESTION: Can cargo containers be installed on properties and used as accessory storage structures?
RESPONSE: Yes, under certain conditions, cargo containers may be used in residential, multi-family residential, commercial, and industrial zones as accessory storage structures. Under the provision of this Code Guide, semi-truck trailers are not considered cargo containers.
I. Conditions for Using Cargo Containers as Storage Structures
Criteria for Installation of Cargo Containers. The PP&D Director will approve the installation of cargo containers using the provisions of this Code Guide provided the containers meet the following criteria:
- Containers are used as storage only;
- Containers are not used as shops, studios, hobby rooms, offices, lunch rooms, sales areas, playhouses, or other similar uses;
- Containers are not used for storage of motorized passenger vehicles;
- Containers are not stacked on top of each other;
- Containers are not classified as a High-Hazard Group H occupancy; or
- Containers are not equipped with plumbing or electrical power or lighting.
Cargo containers not meeting the criteria above must meet all applicable requirements of the Zoning Code and Building Code for a site-built structure.
- Occupancy Classification. Cargo containers shall be classified as follows:
- Containers used accessory to one or two family dwellings: Group U occupancies.
- Containers used accessory to commercial facilities: Group S, Division 1 occupancies.
- Zoning Code. Containers must meet all applicable use and development regulations of the Zoning Code. For example, use regulations may prohibit storage containers from being leased or used as self-service storage. Development regulations such as building setbacks, building coverage limits, or special overlay zones, may affect if or where a container can be placed on a site. For more information, call 503-823-7300.
- Stormwater Management. Containers that are used to store certain materials, such as solid waste or liquids, may trigger source controls. Please contact the Bureau of Environmental Services for more information at 503-823-7740.
II. Building Permits.
- Building Permits Required. Following is a list of situations that require building permits. Requirements of this Code Guide and the Zoning Code must be met even if a building permit is not required:
- Containers used accessory to one or two family dwellings. Containers greater than 200 square feet in floor area and greater than ten feet in height, measured from the finished floor level to the average height of the roof surface, require a building permit. Containers 200 square feet in floor area and less and less than ten feet in height, measured from the finished floor level to the average height of the roof surface, do not require a building permit.
- Containers used accessory to commercial buildings.
- Except as noted in (b) below, a building permit is required to install containers accessory to commercial structures.
- Containers that are used by a contractor for storage of construction materials on a site that has a valid building permit and that remain on the site only for the duration of the construction activity are not required to have a building permit.
- Such containers shall be located on the site for which a building permit has been issued or on a site immediately adjacent to the site of the construction activity that has been approved for use by the contractor as a staging area.
- The containers shall be removed from the site not later than thirty (30) days after the building permit for the construction has received final inspection.
- Multiple Containers. More than one container may be installed under a single permit. Contact the Permitting Services Division of PP&D for permit process information.
- Permit Documentation. Permit documentation shall include a site plan, a floor plan of each container to be installed, and any details required to demonstrate compliance with the installation requirements outlined in this Code Guide.
- Permit Fees. Fees for permits shall be calculated based on a valuation that includes the cost of the container(s) and the cost to install the container(s), including any site work necessary to prepare the site for the container(s).
III. Specific Design Requirements
- Foundations and Tie Downs. Where containers are placed on firm, level, undisturbed natural grade or on an existing paved parking area or storage yard, anchor tie downs or permanent foundations are not required.
- Ventilation. Containers need not be provided with additional ventilation.
- Egress.
- Doors. Containers shall be provided with an egress door not less than 3 feet wide by 6 foot, 8 inches high. The standard doors that the containers are equipped with may qualify as the required egress door provided they meet the minimum size requirement as stated above and provided they are equipped with a mechanical latch or other similar mechanism to hold the door in the open position when the structure is occupied.
- Thresholds and Landings.
- Containers used accessory to one or two family dwellings. Threshold height and landings at doors for containers need not comply with Building Code requirements provided the container is used only for storage of materials belonging to the owner or tenant of the residence on the subject site.
- Containers used accessory to commercial buildings. Threshold height and landings at doors for containers need not comply with the Building Code requirements.
- Drainage. Containers up to a maximum of 320 square feet of roof area are not required to be provided with gutters or downspouts or other storm water collection system provided the sheet flow of storm water from the container is contained on site and not allowed to encroach on adjacent property or public right of way.
HISTORY: UBC/5/#1 & CABO/1/#2 replaced Policy & Procedure # D-61 July 1, 1996. Revised March 1, 1999, April 3, 2006, August 22, 2007, and January 29, 2013.
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