These are basic guidelines that apply to all lamps - but they are only guidelines, so feel to break them if you feel it suits your lamp better.
- Total lamp height (to highest point) no more than 1.5x taller than the height of the surface it is sitting on. In my opinion, this is a very tall lamp, and most are shorter than this
- If the lamp base height is from the table top to the bottom of the lampshade, lampshade diameter should be lamp base height ±5cm
- Another guide for lampshade diameter is twice the maximum diameter of the lamp body
- Lampshade height should be 65 - 90% of the lamp base height, i.e. about 1/3 of the total lamp height
- Max diameter of lamp or lampshade less than the smaller of table width or depth, so the lamp doesn't extend past the table surface
- Table lamps don't want to be taller than any floor lamps in the room
- For a standard lightbulb, the bottom of the lampshade is typically 2.5cm below the top of the bulb holder
- The larger the room, the larger the lamps need to be
- Typically 140 - 160cm high - some are up to 240cm tall, but these are harder to fit in many rooms. Lower ceilings require lower lamps
- Taller lamps light a wider area
- To avoid glare, the base of the lampshade must be at or below eye level (Standing or seated, depending on location)
Intended to give light for activities like reading
- Typical height of top of side table 72cm
- Guideline total lamp height 60 - 85cm
- Bottom of the lampshade should be at about eye level when seated, to give good illumination without exposing eyes to too much glare directly from the bulb.
Aim is to give enough light for reading, without disturbing your partner on the other side of the bed
- Typical bedside table top height 68cm - should be close to the height of the top of the mattress
- Guidelines for total lamp height are table top height plus 5 - 8cm, or simply 60 - 70cm
- Bottom of the lampshade should be about shoulder to chin height when sitting up in bed
- Maximum diameter of the lamp/lampshade should be about 1/3 of the width of the bedside table
- Lamp switch wants to be easily reached from the bed, e.g. on the cord close to the lamp base (if the cord is on the bed side of the table), or on the base lamp, and not too high, i.e. a maximum of 53 - 71cm above the table height
Aim is to give a good light for reading, writing and computer use. Use taller lamps to illuminate a wider area, and lower lamps for more focussed lighting.
- Typical office desk height 80cm
Here I mean any lamp that is suspended from or attached to the ceiling. Ceiling lamps are attached to the ceiling. Pendant lamps hang from a cable or chain, and may be a single bulb and shade, or possibly more than one as visually discrete units (but all connected to a single ceiling rose), whereas a chandelier is a single lamp with multiple bulbs (and not necessarily any cut glass!). I'll refer to them all as pendants from now on, unless there's a need to differentiate.
To enhance the ambient light in a room, you may use an uplight pendant - the light bounces off the ceiling and then round the room, with some going through the shade if translucent. Or a pendant without any shade round the bulb(s), such as a pendant with a designer statement bulb, or a chandelier.
To improve task lighting, a downlight pendant is best, directing the light down over the task. The shape of the shade and height above the worktop will determine the level of task lighting.
Another option is a lamp with a cylindrical shade. Some of the light will go downwards, giving a low intensity task light, whereas the rest will go up and bounce off the ceiling, or pass through the shade if translucent, to give more ambient light.
It may be worth considering a retractable cord system, especially with a downlight pendant. It can be lowered to give brighter task lighting, or raised to give more ambient light, and to increase the headroom for those walking underneath.
For ambient lighting, the ideal diameter (in cm) is found by adding the width and length of the room (in m), and multiplying by 8.3. The depth of the lamp (in cm) wants to be around 20 - 25 times the ceiling height (in m). The bottom of the pendant wants to be 30 - 50cm below a 2.4m ceiling, adding 2.5cm to the drop for every additional 0.1m of ceiling height, and maintaining clearance below the lamp if people will walk below it. Plus, the lamp doesn't want to be any lower than the door frame.
Where people may walk underneath the lamp, you want a clearance of no less than 2.1m. With the standard ceiling height in modern British homes being 2.4m, this give 30cm depth for any ceiling light - though this isn't a problem if it is over a table or worktop.
If the light is going over a table or worktop, a clearance under the light of 75 - 90cm is a good start for a large lamp like a chandelier, and a 2.4m high ceiling. To keep things in proportion, add 2.5cm clearance for every additional 0.1m of ceiling height. Diameter wants to be between 2/3 and 3/4 of the table width, or 1/3 of the table length if it is a long table with two lights over it. Pendants, generally being a bit less dominant visually, can be 10cm lower. Their diameter doesn't want to be more than the smaller of the table width less 30cm or 1/3 the table width, and if hung in a row the spacing (cord to cord) doesn't want to be less than the greater of twice the lamp diameter or 60cm.
Note that some pendant lights can be heavy. It is important to ensure that the ceiling hook or rose is strong enough, as well as its attachment to the ceiling, and the cable or chain supporting the lamp.
Height typically around eye level (1.5 - 1.8m above floor level) (lower in bedrooms), but look at the lamp design to think about glare. Spacing 2.5 - 3m, depending on the fitting size.
Think if they will get in the way of people, especially if protruding more than 10cm and at or below shoulder height.
For wall washing/grazing lights, mount the lights near the ceiling or floor. The closer the light is to the wall, the more it will show irregularities.
May be switched at the light, or remotely with the other room light switches. If there's a switch on the light, it can still be switched remotely if the light is left on. If there isn't a switch on the light, a wall switch can be installed below or beside it. Think about the best switch type - push button, toggle, rocker, pull cord?
Power can come from cables in the wall, or from a power cord going down to a plug. But you can design so either can be used.
The following table is a guide to the diameter of the bottom of the lampshade for different lamp types:
|Lampshade Width (cm)||Lamp Type|
|7.5 - 15||Chandeliers and very small wall sconces|
|15 - 20||Thin, small based table lamps|
|20 - 25||Very small bedroom lamps and small wall sconces|
|25 - 30||Candlestick lamps and medium size wall lamps|
|33 - 36||Small - medium floor and table lamps, and swing-arm lamps|
|38 - 41||Most average size floor and table lamps|
|43 - 48||Full size table and floor lamps|
|50 - 60||Larger and wider body lamps|