Temporary Signs

City Code Requirements for Temporary Signs

Temporary signs alert people to information about short-term activities or issues, such as garage sales, open houses, grand openings, an event, or a weekend sale, or the sign may express an opinion about a particular topic. The criteria for temporary signs depends on where the sign will be located.  The information below details where you can place your signs, what kinds of signs are allowed, and information on other requirements.

Signs in the Public Rights-of-Way (along city streets)

Signs can be displayed in the area along the public streets from 5 a.m. on Fridays until 7 a.m. on the following Monday. No permit is required, and there is no limit to the number of signs that can be located in the public rights-of-way. However, no signs can be placed in a street, sidewalk, roundabout, or median. Signs must be placed at least 50 feet away from all intersections and 5 feet away from the curb or from the edge of the road. Refer to the diagram below.

All temporary signs in the rights-of-way can be no larger than 6 square feet in size (for example a 2 ft. x 3 ft. sign) and no taller than 4 feet in height.  These signs must stand on their own; they cannot be attached to stop signs, street signs, vehicles, utility boxes, fences, poles, or trees. Nothing can be attached to the signs, including balloons, pennants, or moving parts. Temporary signs may not be illuminated.

City staff will remove any sign that does not follow these guidelines or falls into the sidewalk or the street.

A diagram of a t-intersection pointing out a sign placed directly at the 'T' as not allowed.

Signs on city of Thornton Property

Signs may not be installed on city property, including the property in front of City Hall, the recreation center, parks, and other facilities.  However, if the city has issued a permit for the use of the property by a person or group, such as a park pavilion, then signs associated with that use may be displayed for the duration of the permit period.  Signs installed on city of Thornton property in violation of these provisions will be removed and disposed of without notice.

Signs on Private Property

Temporary signs may be located on private property with the permission of the property owner. Signs cannot obstruct drivers' views of oncoming traffic at intersections.  Signs cannot block public access ways such as sidewalks, driveways, and doorways.  The following summary provides general information about displaying temporary signs.

The charts below indicate the amount of allowed signage for residential and nonresidential (commercial) private properties, and for undeveloped land.  If you have other questions, contact Code Compliance at 303-538-7517 or code@ThorntonCO.gov.

Allowed Signage for Residential Properties

Residential properties include those with single-family homes, apartments, townhomes or condominiums, manufactured home parks, etc.  Some churches have residential zoning as well. The amount of signage allowed depends on the size of the property.  Most single-family homes are located on lots that are less than one acre.

Property SizeSign Size
Maximum sign area per property
Less than once acre72 square feet
One acre or larger 100 square feet
Maximum sign height (measured from the ground to the top of the sign)
Less than once acre6 feet
One acre or larger 10 feet

Banners are based on the height of the structure that the banner is attached to.

Allowed Signage for Nonresidential (Business) Properties

Nonresidential properties include businesses located in shopping centers, stand-alone stores, and other locations operated as retail, service, and similar uses.  This does not include businesses operated from a residence, called home occupations, which must comply with the residential property requirements listed above.

The maximum sign area allowed is based on the size of the space occupied by the building user or tenant.  The amount of signage allowed depends on the size of the tenant space and the zoning of the property.

Nonresidential Property Sign RequirementsNeighborhood Service and Eastlake ZonesOther Nonresidential Zones
Maximum sign area per building user or tenant (based on the floor area of the business) 
Less than 25,000 square feet60 square feet60 square feet
25,000 to less than 100,000 square feet105 square feet105 square feet
100,000 square feet or larger230 square feet230 square feet
Maximum sign height (measured from the ground to the top of the sign)
Freestanding signs and feather flags10 feet20 feet

Banners are based on the height of the structure that the banner is attached to.

Balloons, air dancers, pennant strands, inflatable devices, and other signage used for a special event may require a special event sign permit. Permits may be requested at the Building Inspection Division, 9500 Civic Center Drive.  For additional information on a special event sign permit, contact the City Development Department at 303-538-7295 or citydevelopment@ThorntonCO.gov.  

Allowed Signage for Undeveloped (Vacant) Properties

You must have the permission of the property owner to display your temporary sign on another's private property.

The amount of signage allowed depends on the zoning and size of the property.  If you are not sure of the zoning of the property, contact the City Development Department at 303-538-7295 or citydevelopment@ThorntonCO.gov.  You will need the street address or the tax parcel number of the property in question.

Residential Zones

Undeveloped Property Sign RequirementsLess than one acreOne acre or larger
Maximum sign area per property120 square feet120 Square feet
Freestanding signs and feather flags6 feet10 feet

Maximum sign height  is measured from the ground to the top of the sign). Banners are not allowed on undeveloped land.

Nonresidential Zones

Undeveloped Property Sign RequirementsNeighborhood Service and Eastlake ZonesOther Nonresidential Zones
Maximum sign area per property150 square feet250 square feet
Freestanding signs and feather flags10 feet20 feet

Maximum sign height  is measured from the ground to the top of the sign). Banners are not allowed on undeveloped land.