Outdoor Lighting Ordinance

Boulder Light Meter Readings 

In 2003, the City Council approved a new outdoor lighting ordinance. The objectives of the ordinance are to prevent light trespass, reduce light pollution (also known as “sky glow”), reduce excessive glare, promote energy conservation, and improve safety and security (including addressing the special nighttime lighting needs of an aging population).

The objectives of the new ordinance are accomplished by:

• Establishing maximum allowable lighting levels which are based on zoning district and use.
• Requiring lighting to be reasonably uniform to minimize light/dark contrast.
• Requiring all light in excess of 2400 lumens (roughly equivalent to a 150 watt incandescent light bulb) to be “white light," which includes metal halide, fluorescent, and induction light bulbs, because of superior color rendering properties.
• Requiring the use of full cut-off light fixtures and shielding to reduce glare, light pollution and light trespass.

How does this affect my property?

• The ordinance allows property owners with existing lighting installations that are not in compliance with the ordinance 15 years to comply.
• Property owners with building permits for multifamily dwelling units and non-residential projects, which include outdoor lighting improvements, will have to submit lighting plans that meet the requirements of the ordinance.
• All new buildings must comply with all the requirements of the ordinance. Redevelopment and remodeling will have to meet certain levels of compliance based on “thresholds." The thresholds and required lighting improvements are based on the valuation of the proposed building improvements.
• Lighting plans are not required for single-family detached dwelling units. There are, however, some minimal requirements for single-family dwellings such as requiring the use of shielded light fixtures.

Check Your Outdoor Lightbulbs

Noncompliant fixtures are those that do not shield glare from adjacent streets or properties. To bring a light into compliance, owners need to, at a minimum, replace visible bulbs with one not exceeding 900 lumens (equivalent to a 60 watt incandescent bulb or 15 watt compact fluorescent bulb). Spot lights and flood lights must be re-aimed so that they don’t shine across property lines. The lumen rating is commonly shown on the bulb packaging in conjunction with the wattage rating.

Some acceptable fixture examples are shown below:

The glass is frosted which diffuses the light, obscures the lightbulb and reduces glare. The other two light fixtures are full cut-off fixtures that no light projects above horizontal thus reducing light pollution. It qualifies as a fully shielded fixture. If mounted at appropriate heights, the bulb is not visible from adjacent streets and properties. 

This is not an acceptable light fixture. Existing fixtures will have to be replaced by Aug. 15, 2018.

Questions about the ordinance can be directed to the P&DS Service Center at 303-441-1880.

Last Updated on Wednesday, 16 January 2013 13:11