Q: How much light does my room need?
This is really a matter of personal preference as some people prefer a really bright light whilst others may like to have a more subdued effect. If you are changing the lights in your room consider whether you want more or less light than you already have. It may also be worth considering fitting a dimmer switch so you can control the level of light, but check that the fitting and bulbs you choose can be dimmed. For instance, if you are reading in your sitting room you will want a much brighter light than if you are watching TV.
As a basic guide to determining the level of light you need calculate your room size in square meters and multiply by 25 (for incandescent lamps or conventional bulbs), by 15 (if using halogen bulbs) or by 19 (for fluorescent or low energy bulbs). For example, if your room measures 4M x 5M it has an area of 20 square meters. If you are using conventional bulbs multiply this by 25 giving a total wattage of 500 watts, or a light level of around 5000 lumens required. The lumen level of each bulb will vary depending on the type of bulb and manufacturer, check the specific lumen level of each bulb to measure up with the overall "target".
Q. What are ‘Lumens’? Why can’t we just keep 100 Watt light bulbs?
Traditionally the brightness of a light bulb has been described by its wattage, everyone knows a 100 watt lamp will be brighter than a 60 watt lamp. This is a good way of describing the difference in brightness between two bulbs of the same type but with new technologies now available wattages are no longer the means by which bulbs are differentiated. Today the same quantity of light can be produced by an incandescent bulb using 60 watts, a halogen bulb using 42 watts or a compact fluorescent lamp using 15 watts. This causes confusion and so with the intention of fixing this problem 'lumens' are now included showing the 'true' measurement of the lamps brightness. In effect a universal measurement of any lamps brightness, the higher the 'lumens' the more light emitted.
Q. Should I choose lights that are pointed up or down?
This is largely a matter of personal choice. However there are a few things to consider. Lights that point up reflect most of their light back down off the ceiling and will work best if you have a white or pale coloured ceiling. If you choose lights with glass shades they will allow light through whether they are pointing up or down and clear shades will obviously let more light through than frosted or coloured shades. Consider how much light you need in the room taking into account any other lights (wall lights, floor lamps etc.) that you have in the room.
Q. At what height over my dining table should i hang my light?
The basic rule here is that the bottom of your ceiling light should be between 30" and 34" from the top of your table. If your ceiling is taller than 8' then add another 3" for every additional foot. Another suggestion is to consider having a rise and fall suspension over your dining table so that you can adjust the height of the light as required.
Q. What are the advantages of led lighting?
The main advantage of LED lighting is undoubtedly the reduced power consumption. The efficiency of the newer LED light bulbs is more that 5-6 times higher than standard incandescent bulbs which, put another way, means that LED bulbs use only about 1/6th of the energy to produce the same amount of light. Because LED bulbs direct most of their light where it is needed they can be up to 10 times as effective in many instances, thus reducing energy use by up to 90%. LED bulbs are not only highly efficient but last considerably longer than incandescent or fluorescent bulbs. The operational life of LED bulbs can vary from 40.000 up to 100.000 hours. Even at 40,000 hours this is 4.5 years of continuous operation which under average usage means these bulbs will last over 10years. Compared to a halogen spotlight bulb, LED spots last up to 24 times longer. LED bulbs do not burn out like other bulbs they just gradually decrease in light output. The lifespan is based on time it takes for the bulb to fall to 70% of its original output although of course the bulb will still continue to function after this. LED light bulbs are eco-friendly. They contain no harmful mercury, do not emit any CO2 and can be recycled without harming the environment. They do not produce damaging UV radiation. Because LED bulbs approach 90% efficiency i.e. 90% of the energy is converted to light and only 10% is lost as heat energy, they are cool to touch. Compare this to an incandescent bulb where 80% of the electrical energy is lost as heat, making these bulbs very hot to the touch. Finally LED bulbs come on at full intensity, perform well when frequently switched on and off, can be used with a dimmer switch and there is no “buzzing” or “flickering”.
Q. Are there any disadvantages with led lighting?
The initial cost of LED bulbs or light fittings is much higher than conventional alternatives. However when you look at the energy saved and the cost of replacing conventional bulbs the payback is enormous. Because LED bulbs are not available in very high wattages you may need more LED lights to produce the required light level. However you will still be using up to 85% less electricity.
