Lightbulbs 101 - An Overview of the Common Lightbulb


I just had some canned lighting installed at my home and boy, what a difference it makes. Our home lacked overhead lighting in all the bedrooms so adding the lights was well worth the investment. There are quite a few things to consider when choosing your lighting but one big one is....the lightbulb!


Common types of lightbulbs

  • LED - Most energy-efficient and long-lasting but also the most expensive

  • CFL - Contain mercury and must be disposed of properly

  • Tungsten incandescent - Least efficient and cheapest but 90% of the energy consumed by an incandescent bulb is lost as heat

Brightness: Light output is measured in lumens, not watts. A 60-watt incandescent bulb provides roughly 800 lumens: 40W, 450 lumens; 75W, 1100 lumens; 100W, 1600 lumens; 150W, 2600 lumens.


Energy Used: The amount of electricity that a lightbulb consumes is measured in watts.

  • A 60W tungsten bulb consumes 60W.

  • An 800-lumen LED bulb (equivalent to the 60-watt tungsten) uses approximately 14W of electricity.

Light Appearance: Light appearance refers to the “color” of the white light. Light color is represented in Kelvin, a temperature measurement.

  • 2700K is roughly the equivalent of a tungsten bulb. Warm & cozy. Great for living rooms and bedrooms

  • 3000K roughly the equivalent of a halogen bulb. Crisper and good for functional light in kitchen and bathrooms

  • 4500K considered equivalent to daylight, and appears blueish. Great for garages and laundry rooms.

My pet peeve......Mismatched light color. A bedroom with 2700K lighting at the ceiling and 4000K in the nightstand lamp looks awkward and can be very noticeable.


Color Rendering: This measurement is important when illuminating artwork or when highlighting decor. Low CRI ratings make the colors in a room seem flat, while high CRI makes color pop.