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Green Building Resources for Existing Affordable Housing


Fluorescent lighting is energy efficient and while prices range widely, it is also generally cost effective. There are some misconceptions about the fluorescent fixtures on the market today due to historically poor quality and performance. However, the models available now have eliminated flicker, do not have delayed start times, provide greatly improved rendition and color temperatures, and some models are even compatible with controls such as dimmers.

What Type of Lighting Should I Specify?

  • Your lighting should be at least as efficient as the ENERGY STAR fixtures.

  • Compact fluorescent lamps (CFLs) and T8 linear fluorescent lamps using electronic ballasts should replace incandescent bulbs and T12 lamps using magnetic ballasts.

  • T8 lamps are available straight or U-shaped. Super T8 and T5 models are even more efficient than the T8s.

  • T8 lamps use less electricity than T12 lamps (32 watts vs. 40 watts) and tend to last longer.

  • While the price of the T8 bulbs is comparable to the T12 bulbs, you may have to replace ballasts if your building currently uses T12 lamps so you may have some incremental costs.

  • Use hard-wired CFLs for any new and replacement fixtures. A typical pin-based CFL should last between 10,000-12,000 hours. Using pin-based fixtures ensures that screw-in incandescent bulbs cannot be used by residents. You may want to consider providing CFL bulbs for your tenants.

  • While they are more efficient, the major disadvantage to using CFLs is that they contain small amounts of mercury. Mercury can be harmful to human health and can end up in water and land, where it can be washed into lakes and rivers, harming our wildlife.

  • CFLs should not be turned on and off frequently or exposed to heat where possible because they will not last as long.

Other Retrofit Considerations

  • Any recessed cans should be insulation contact air-tight (ICAT) compact fluorescent models.

  • LED exit signs should replace fluorescent and incandescent exit signs wherever feasible.

  • Combine lighting with controls to save electricity such as occupancy sensors in stairwells (where code will allow), janitorial closets, storage spaces, trash rooms and other areas where lighting is not needed continually.

  • Ensure that the elements of your lighting system are compatible: ballast, lamp, dimmer, sensors – incompatible bulbs and fixtures can reduce the maximum life span and efficiency. In most cases, it is best to use the manufacturer’s recommended compatible elements to maximize the life span of your lighting system.

  • Ensure that the lamps are intended for the particular fixture you are installing and that the orientation is appropriate.

  • Many utilities have rebates for lighting which might make more expensive options feasible for your project – investigate your options before committing to a particular choice.

  • Consider reducing your lighting power density (LPD) which is measured in watts per square foot (watts/sq.ft.). Per ASHRAE 90.1-2007 which may be more stringent than your local code requirements, recommended LPDs for multifamily common spaces include: inactive stairs (0.4 watts/sq.ft.), active stairs (0.6 watts/sq.ft.), and corridors (0.5 watts/sq.ft.). It is also recommended that the LPD for the residential units be reduced to 0.7 watts/sq.ft. when possible.

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Two Types of Fluorescent Lamps

Source: EnviroLighting

Tubular Fluorescent Lamps

The "T" designation for fluorescent lamps stands for tubular which is the shape of the lamp. The number after the "T" gives you the diameter of the lamp in eights of an inch.

Compact Fluorescent Lamps (CFLs)

CFLs come in pin-based and screw-based configurations. Wherever possible, it is better to install pin-based fixtures as they will only accept fluorescent lighting whereas a screw-based fixture will accept incandescent bulbs.


  • While the average LED lasts for 50,000 hours compared to 10,000 hours for a CFL, currently most LED lighting is still cost prohibitive.

  • Use less energy than both incandescent and CFL bulbs and may prove to be cost effective option when considering the life-cycle cost analysis.

  • Do not contain mercury.

  • Ideal for use in hard-to-reach areas as the bulbs do not have to be replaced very often.
    Source: C. Crane Company



Measurement of light output from a lamp; all lamps are rated in lumens. For example, a 100-watt incandescent lamp produces about 1750 lumens. When looking for a light bulb and determining the light level you need, pay attention to the lumen output rather than the wattage; lumen describes light output, wattage describes energy used.


Measures the efficiency of a lamp. This is the ratio of a lamp's light output to the electric power it consumes and is measure in lumens per watt (LPW).
Source: Smart Home Systems

Design Considerations

  • Depending on the extensiveness of your retrofit scope, you may have the opportunity to re-think some of your design decisions which may have a direct impact on your lighting strategies.

  • Take into account the different types of spaces and uses throughout a multifamily building. The lighting plan should be strategic about the amount of light needed in the various spaces.

  • The lighting design should take advantage of daylighting opportunities where possible and reduce the lighting power density (LPD) [LPD is measured in watts/sq.ft.] necessary if feasible.

  • Lighter color walls are more reflective and can reduce the amount of necessary lighting.

  • Light the walls rather than the center of the room if possible, this will make the space seem larger and will allow the light to reflect off walls back into the room.

  • Closets should use ceiling surface-mounted lights rather than recessed.

  • Low ceiling spaces should utilize uplighting in order to make the ceiling feel higher.

Exterior Lighting Considerations

  • Exterior lighting should be at least as efficient as the ENERGY STAR fixtures.

  • Include daylight sensors, such as photocells and/or time clocks so the fixtures are not used during daylight.
    • Photocells cannot be controlled by the user, so if there is too much ambient light at night the light controlled by the photocell will not come on.
    • The location of the photocell is important – the illumination from the light connected to it must not touch the photocell or the photocell will continually turn the light on and off.

  • Try to keep the number of fixtures to a minimum while still meeting safety and security needs.

  • Avoid light pollution by pointing lights toward the ground and using full or partial cut-offs where possible.

What ENERGY STAR lighting has worked best for you in your building? Let us know.

Hazardous Waste Protocol

  • All fluorescent lighting contains mercury, an environmental toxin. Consider requesting the lowest mercury content lamps possible when making your purchasing decisions.

  • Fluorescent bulbs must be disposed of properly. In order to ensure proper care, a waste management protocol needs to be established.

  • Find more information regarding disposal and recycling of fluorescent bulbs and locate your nearest recycling center.


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