HOW MUCH LIGHT DOES MY ROOM NEED?
Sounds like an easy question to answer – but is it?
Determining the correct lighting level for a room can be a complicated business and will depend on many factors. Some people prefer brighter lights whilst others may want a more subdued effect. The level of light for different rooms will also vary – you will want brighter lighting in a kitchen for food preparation whilst you may want a more relaxed lighting effect in your sitting room and bedrooms. Many rooms perform several different functions and will require versatile lighting to cater for these tasks. It is also important to consider how much natural light the room has and how light is reflected from the surfaces in the room.
Lighting is often overlooked and only considered once the decorating has been finished which is a great shame – you have spent a lot of time and money to achieve the look you are after only to find that something is missing!
To help you calculate the lighting levels you need – simply follow the steps set out below. This will give you the basic level of light for your room.
- Firstly measure your room to find its floor area – for instance, if your room measures 4 metres by 5 metres then it has an area of 20 square metres (4 x 5=20). Easy so far!
- If you are using old style incandescent bulbs then multiply by 25 to give you the total wattage needed for the room, so in our example it would be 20 x 25 = 500 watts – your room will need around 500 watts.
- If you are using halogen spotlight bulbs or other halogen bulbs multiply by 15 rather than 25 i.e. 20 x15 = 300 watts – you will need roughly 300 watts.
- For low energy compact fluorescent bulbs simply multiply your square metres by 19, so in our example this would be 20 x 19 = 380 watts
- But what about low energy LED bulbs? With LED bulbs it is a little bit different as light levels are now quoted in lumens. Lumens are a more accurate measure of the brightness of bulbs and the more lumens in a bulb the brighter it will be. In order to roughly estimate the lumens that are needed for a room you will need to multiply the area of the room in square metres by 100. In our example the room was 20 square metres so the lumens required will be 20 x 100 = 2000 lumens.
LED bulbs are a great choice as they are more efficient and last a lot longer – they may cost a little more but work out cheaper in the long run. LED bulbs usually have the incandescent equivalent wattage on the packaging which can help until we all get used to lumens! One thing to bear in mind with LED bulbs is that they vary in their efficiency and better quality LED bulbs will be brighter. For instance a 3 watt LED bulb from one manufacturer may provide more lumens that one from another manufacturer – so look at the lumens rather than the wattage.
The rule of thumb calculations we have used will provide you with a basic light level only and you will need to increase the lumens in areas where you require brighter lighting. Each room will have different requirements and you will almost certainly need more that this in most rooms. A kitchen would typically need at least double this light level in lumens.
A few extra things to think about –
- If you are looking to change the lighting in your room consider whether you want more or less light than you already have.
- If you have rooms with particularly high ceilings you will need to increase the light level.
- If you add shades to light fittings this will reduce the light level so you may need to compensate for this in your calculations.
- A combination of different types of lighting is often best. General or background lighting from ceiling lights and wall lights should be combined with accent lighting from table lamps and floor lamps and direct task lighting such as desk lamps, picture lights and reading lights.
- Consider installing dimmer switches, so you can control the level of light in multi-functional rooms, however do check that the bulbs you opt for are able to be dimmed.
- As we get older we need more light so increase the light level if necessary.
- Rooms decorated in darker colours will need more light.
If you are struggling, let us help you – simply email us firstname.lastname@example.org and we’ll be happy to assist.
Now you know how much light is you need, the next question is what style of light is best for your home?
Our Lighting Through the Ages Guide may be useful or browse any of the following –