Save the Night | Be the Solution, Stop Light Pollution
General Requirements
Outdoor Lighting Bylaw
1. SHIELDING
Unless falling within an exception or general exemption, outdoor lighting must be fully shielded if the lumen output is more than 600 lumens (Section 102-4A).
Fully shielded means that all light shines below the horizontal plane where the light is emitted and no light is emitted upwards, as shown in this drawing (Section 102-3). As the drawing illustrates, that means no portion of the bulb is visible, either through openings on the side or top or below the fixture.
Click here for examples.
Exceptions:
- String lights, temporary holiday lights, flag lighting, and sports lighting on nonresidential properties are allowed even if they are not fully shielded, provided the lighting complies with the specific requirements applicable to them (Section 102-4A(1)-(4)).
- Any lighting that falls within a general exemption is allowed even if it is not fully shielded, including temporary safety and security lighting (Section 102-7).
2. COLOR TEMPERATURE
Unless falling within an exception or general exemption, the color temperature of outdoor lighting must be 2700K or less (Section 102-4B).
Exceptions
- Any lighting that falls within a general exemption, including temporary safety and security lighting (Section 102-7).
- Temporary holiday lights and sports lighting on nonresidential properties, provided that the lighting complies with the specific requirements for them (Section 102-4B(2) and (3)).
- Up to 3000K may be used if a 2700K or lower bulb or fixture is not commercially available for the use in question (Section 102-4B(1)).
3. BRIGHTNESS
Total Lumens Allowed For Unshielded Fixtures (Combined)
Not counting temporary holiday lighting and any lighting that falls within a general exemption, the total lumens allowed for fixtures that aren't fully shielded (all properties) is 5,000 lumens multiplied by the number of acres, OR 2,000 lumens, whichever is greater. This means you are allowed at least 2,000 lumens in unshielded lighting regardless of the size of your property. See Sections 102-4C(2) and 102-7.
Examples
- For a property that is .5 acres, up to 2,500 lumens of lighting that isn’t fully shielded is allowed (5000 x .5 = 2500).
- For a property that is .25 acres, up to 2,000 lumens of lighting that isn’t fully shielded is allowed because 2000 is greater than 5000 x .25.
Total Lumens Allowed Per Site (All Fixtures Combined)
Not counting temporary holiday lighting, nonresidential sports lighting, and any lighting that falls within a general exemption, the total lumens per site is capped as follows:
Residential: 20,000 lumens per acre
Nonresidential: 40,000 lumens per acre (additional lumens allowed for canopies at gas stations and banks)
Need help converting square feet into acres?
Here's a handy online calculator for that:
https://www.thecalculatorsite.com/conversions/common/square-feet-acres.php
4. DURATION
Residential Properties
Outdoor lighting on residential properties must be turned off between 11pm and 6am.
Exceptions:
- Safety and security lighting is not subject to this restriction.
- Flag lights may be used throughout the night IF they meet the specific requirements for them.
- All lighting that falls within a general exemption may be used throughout the night.
See Sections 102-4D and 102-7.
Nonresidential Properties
Outdoor lighting on nonresidential properties must be turned off within one hour after closing and may not be turned on until one hour prior to opening.
Exceptions:
- Safety and security lighting that is 600 lumens or less is not subject to this restriction.
- Safety and security lighting that is brighter than 600 lumens is not subject to this restriction IF it is dimmed to at least 50% during the restricted hours.
- Flag lights may be used throughout the night IF they meet the specific requirements for them.
- Sports lighting must be turned off by 10pm or within one hour of the end of active play, whichever is later.
- All lighting that falls within a general exemption may be used throughout the night.
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