The lighting in any given building needs to be designed with three different requirements in mind, and in this order-
Task lighting is that lighting which illuminates the areas where work (tasks) will be performed. This can include desks, counter tops, work benches, factory assembly locations, patient exam rooms, operating rooms, dental chairs, salon hair stations, stages, bars, cooks lines, butcher shop tables, among countless other locations.
Accent lighting is that lighting which illuminates things such as wall hung pictures, floor standing statues, niches, coves, trinket shelves etc.
General lighting is that lighting which illuminates walk ways, general assembly rooms, church seating areas, stairwells, and all the other areas that were not taken care of by task and accent lighting.
Designing your structure's lighting system in this order will cover all of the areas which need illuminating. If you are a home owner and are about to embark on an ambitious remodeling project consider these points before submitting your plans to a contractor for bid. The task lighting in most homes will include the kitchen counter tops, sofa reading areas, garage work benches, bed time reading, bath vanity's, and showers and tubs. These areas will need sufficient light for any tasks to be performed. Kitchen counter tops are known for being dimly lit after a recent remodel because the recessed can light that was supposed to illuminate it is located behind the person standing at the counter top. The person's body is projecting a shadow onto the counter top. These kitchen recessed can lights should be placed just outside of the upper cabinet so they shine light down between the upper cabinet and the person standing there, thus illuminating the counter top. This is displayed in the picture at top.
Recessed can lighting is a popular style of lighting but is not without it's drawbacks. Once a can light is installed it is rather permanent in it's position. If a living room is to be illuminated using recessed can lights it is imperative that some thought is given as to the final placement of all the furniture, art work ect. Some of the recessed can lights will need to be placed directly over the sofa(s) for reading purposes, and some will be placed so they highlight some piece of artwork. Keep in mind that can lights tend to shine straight down rather than spreading their light laterally like a surface mounted fixture will. Some home owners are not always content with the placement of their furniture and will want to periodically rearrange it, and this will lead to problems with the lighting. This needs to be considered thoroughly before deciding where to place your recessed can lights. Bedrooms too can be problematic if recessed can lights are to be used as task lighting as many bedrooms are rearranged now and then. Most bedrooms- with the exception of the master bedroom- are small and can be well illuminated with two, or maybe four, recessed can lights simply centered in the room. Desk and work bench lighting is very straight forward and usually done from above with recessed can lights or some sort of hanging lights. Once again, make sure that your are happy with the locations of any ceiling lights you install as they are not movable a few years after the remodel is complete and you have decided you would like to rearrange. Another option would be to install recessed can lights equally spaced in a rectangle so as to bathe the entire room with light. That way you could rearrange with infinite possibilities, but perhaps lacking in style. The bottom picture here is a good example of task, accent and general lighting all used in the same room. The three lights in a line horizontally towards the top will illuminate a dining room table (task lighting) and there will also be two sofas where the table now sits which will have down lights directly over them (task lighting). You can see the area above the fire place is illuminated by two adjustable can lights (accent lighting), and the LED cove lighting adds a nice 'accent lighting' touch. There are a few general lighting can lights to illuminate the walking area to and around the room (general lighting). This customer was very convinced he had decided on the correct locations where his furniture would go when the job was complete.