Choosing the correct light bulb for recessed can lighting can be a daunting task. If you aren't familiar with light bulbs and all the different types it's hard to know where to start. Most folks simply replace burnt out bulbs with what they pull out. Others go to the local hardware store and just buy what "looks" right on the shelf. With a simple analysis, you can choose for yourself what the best light bulb for your application is by splitting out the choices that need to be made.
Obviously, the easiest way to replace light bulbs in your recessed can lights is to pull out the old one and simply purchase that same bulb. If you don't have that as an option, follow the below steps to choose the correct light bulb.
Key Abbreviations to Understand:
I'm going first outline the main letters that you'll see on your current bulb or in your can fixture and what they mean. 40W (or any number followed by a W) = 40 Watt; R16 or BR16 or PAR20 (There are many of these. Most start with a letter or a few letters and are followed by a number) = these are bulb shapes; 120V or 130V (This may or may not be stipulated) = Indicates voltage.
List from Fixture:
Your first step should be to look inside your can fixture. Most will have a sticker on it that will outline about a half a dozen of options that can be used in that specific fixture. I.E. 40W R16
Best Style for your Baffle, Lense or Reflector:
Next, go to the website of the manufacturer that made your can fixture. The 3 major manufacturers are Cooper Halo Lighting (www.haloltg.com), Juno Lighting (www.junolighting.com) and Lithonia (www.lithonia.com). Around the edge of your can you will have what is known as a baffle, lense or reflector (trim). This is a separate piece you will find in your can. Each manufacturer will have their recommended light bulbs to use that will maximize the effectiveness of your particular baffle, lense or reflector. Find this under their "specifications" sheet attached to your particular attachment.
Decide if you want a Spot or Flood:
Some light bulbs like Halogen PAR shaped light bulbs will come two ways: Spot lights or Flood lights. The progression goes from Spot to Flood to A19 which lights up in all directions. Most spots light an area up to 20 degrees in width. Most choose these if they want to light up art work or focus on a mantel or something similar. A flood generally goes from 25 degrees to 60 degrees in swath of light. Then an A19 lights up tan entire area. But not all fixtures are made to have A19 light bulbs in them permanently. In most cases, you'll want flood light bulbs.
What Color of Light do you want?
If you are looking at Compact Fluorescents, you will sometimes have an option of color. And I don't mean pink vs. white. I mean the color of the light that is emitted. If your compact fluorescent says that the color temperature is 2700K, the light will be a soft white color. If it says that it is a 5000K, it will be more of a blue-ish white light.
Type of Light Bulb:
The last thing you'll need to decide is the type of bulb you will want. The main types of light bulbs that people use are Incandescent, some sort of long life incandescent, halogen and compact fluorescent light bulbs. I'm not going to go into the differences in them all here as that is a whole different conversation. Regardless, many times you will have the option to use any of these types of light bulbs in your can fixture. I.E. A BR40 Incandescent is a similar bulb type as a BR40 halogen. The important thing to remember here is to not go over the wattage the your can fixture recommends. Using a light bulb with the wattage too high for the fixture could shorten the life of the light bulb and could even cause a fire in some of the older cans.
By asking yourself these questions before buying, you will eliminate the confusion this purchase can present. And you will be happier overall with your purchase and the look of your room or application.