2. Should it be lit from within, or from above?
If you just want the luminaire to be a beautiful illuminated sculpture, it can be lit by spotlights from above. This can be the most beautiful effect because there are no lamps in the luminaire itself, and so there are no sources of glare.
If, on the other hand, it is there also to provide essential ambient light, so that people can see their way up and down the stairs, lighting from within may be necessary, particularly if the there are several flights of stairs, making the feature light longer.
A large single piece is normally lit from within. Multiple pendants can either be lit from within or from above.
3. If I go for multiple pendants, how should they be arranged?
Though some makers have standard arrangements, others will expect you to decide the quantity, lengths of drop, and combinations of luminaire (colours, sizes, etc.) yourself, so that you can create something site-specific. The most expensive option is usually to have the pendants arranged equally all the way down but you often don't need to do this. Instead, work out where the pendants will be seen from on each floor, and create coherent designs along each of these site-lines. You can then have between the floors just a few pendants connecting each of these groups, or none at all.
The cable has to be rated to carry the weight of the pendant. If the pendant does not contain a lamp, and the luminaire is light, the finest, almost-invisible wire can sometimes be used. A thicker cable is required for a pendant with a light in it, because it needs to be able to carry the electric current.
4. How tall should it be?
The arrangement of pendants, or the single piece, does not need to start right up against the top plate; instead, they can often begin quite a lot lower (which is cheaper, because you will need fewer pendants). Only you can decide where it should start, by taking into account the various sight-lines.
5. How near the floor should it go?
If people are going to be walking underneath it, normally allow 230cm from the floor. Note, however, that these tend to be major feature pieces, designed to add a wow factor. You may want to create the wow when visitors enter the hall through the front door, so check what it looks like from there. If the bottom of the piece is too high up, it may lack impact - or be completely invisible.
If people are not going to be walking under it, again, think of the sight-lines and create a good composition, bearing in mind what else is in the space. You can bring it all the way down to the ground, of course, but do check first for the presence of cats, dogs and children that may want to pull on the piece if they can reach it.
6. How near the bannisters can it go?
Children and drunks may want to reach over and pull at the piece. If they are determined enough, design alone can't prevent this, but if the presence of either is likely on a frequent basis, keep the luminaire more towards the centre and so further out of reach.
Note that in older houses, the space between the bannisters is not always the same on each floor. You have to be guided by the smallest of the measurements in each direction (which may not be on the same floor).
7. Is there anything else that I should be aware of?
Yes! - anything hanging down through a stairwell will be seen from all angles, as people walk up and down
- pendants may move a little in draughts. If this is likely, ensure that they will not bang into the stairs or each other
- please also see Practical Considerations when Hanging Chandeliers.