Whether you have high, low, or sloped ceilings changes the way the space needs to be lit. As a rule of thumb, lights should not hang less than 7 feet above the floor.
Over a table or counter, a hanging light should be hung 30-36 inches above the surface. Within that window is simply your personal preference.
If your ceiling is sloped, a lighting designer can help you find the right fixture for the angle of your ceiling, because not all fixtures will work. Having recessed lighting and track lighting is still possible with a sloped ceiling, but consult a lighting designer before making any purchases so they can help you optimize the light within your space, and make sure you know the angle at which your ceiling is sloped.
Too many light sources, lights that are too bright, or improperly concealed light sources can cause discomfort. Problems like these can be solved with one or more of the following:
- A layered lighting design that is curated to a room and how you use it.
- Indirect lighting, where you can’t see the source of the light directly.
- Dimmers, lower-wattage bulbs, and bulbs with lower color temperatures.
Color of Surfaces or Finishes
The darker the colors in a room’s palette, the more light surfaces absorb and the less light they reflect back into the room. Rooms painted or wallpapered a dark color require more light than a white or light colored room.
Activities Done in a Room
The difficulty of a task depends on its size and contrast and how much speed and accuracy are required.
Most homes do not require very high levels of illumination, except for local lighting of critical tasks, such as hobbies and careful grooming.
Note that the quality of the lighting has a greater impact than the quantity of light. For example, correctly-placed bathroom sconces with a shade that diffuses light evenly will be more effective than brighter sconces that are placed incorrectly or have a shade that causes shadows.
Age of Occupants
Older eyes need more light to see well, especially for difficult or low-contrast tasks, and are more sensitive to glare.
People over the age of 55 may need twice as much light as a 20 year old person, and needs increase from there. Lighting that distinguishes the surfaces of walls and floors (especially changes in level) makes a space much more comfortable and secure for older people.