The beam angle of a lamp is the angle at which the light is distributed or emitted. Lamps such as Halogens (and some LEDs) come in a variety of angles from 4 degrees to 60 degrees with some of the larger halogen lamps up to 120 degrees.
Note that while these abbreviations are commonly used, the angles associated with these vary slightly from manufacturer to manufacturer. These are typical beam angles spread abbreviations, and what they look like:
- SP (spot): 4-19 degrees
- FL (flood): 20-35 degrees
- WFL (wide flood): 36-49 degrees
- VWFL (very wide flood): 50-120 degrees or more
For most domestic household ceiling fitted appliances a beam angle in the 30-40 degrees will be sufficient given the standard height of ceilings and the range, spread and number of light bulbs in the area. Please also note that the wattage, type of light bulb and colour used will also determine the beam angles available.
All great lighting schemes allow the darks to play a supporting role to the lights and you should aim to never over light a space. You can do this by purposefully choosing where the light should fall by carefully positioning your light fittings BUT it’s how the light leaves the lighting fittings that needs consideration too.A fundamental lighting design tip is to actually consider where the darkest parts of the room need to be as well as the lightest. You can actually design your spaces to take back control of where light ends up.
Imagine your room as a blank canvas of darkness and use lighting to sculpt the shadows and use the beam angles from the lamp or fixture to fine tune how it travels and where it will reflect.