Both CFLs and LEDs are available with screw-in bases as replacement bulbs for existing fixtures, but if you are building a new home or remodeling, you might consider fixtures dedicated to one technology or the other. Dedicated fixtures can lengthen the lifespan of the bulb and maximize its strengths. Both CFLs and LEDs play a role in providing ambient, accent, task, and decorative lighting, the four layers that create a well-lit room. But CFLs and LEDs aren’t necessarily interchangeable. That’s largely because CFLs are a multidirectional light source and LEDs are a point source.
Because they are multidirectional and produce large amounts of diffuse light, CFLs work well for ambient, task, and decorative lighting (photos pp. 160-161). They can be used nearly everywhere that incandescent bulbs are used, particularly in table lamps and in shielded sconces, where the fabric or glass adds color to the light. In the bathroom, when they’re used behind opaque glass, CFLs do a great job of lighting your face. In kitchens, in laundry rooms, and in offices, CFLs produce bright-enough ambient light to illuminate worksurfaces.
CFLs are not appropriate everywhere, however. Locations where lights are switched on and off quickly—say an entry hall or a coat closet—are not ideal because CFLs need time to attain their full brightness and because short-cycle switching reduces the bulbs’ lifespan. Also, if you’re using a CFL bulb in an outdoor fixture, make sure that it’s labeled for outside use, which means that the ballast will work in cold temperatures.
