They need to install a new ground wire from the fixture's bonding point to the box. If you HAVE a 3-wire nranch circuit (hot-neutral-ground) the fixture should be grounded by attaching to the grounded box or the ground wire itself. If you have an older circuit that is 2-wire (hot-neutral) it is not really going to make any difference though, you do not have a ground anyway. Note that some wiring methods (AC cable, metal conduit) use the armor or conduit as the ground connection and not a separate wire.

What kind of fixture are you hanging? If it's a bowl fixture, you want it high enough that you won't be looking down into it, seeing the lightbulbs, from the top of the staircase. Whether bowl or something else, you also don't want it so low that it feels like you run into it on the way down. We recently remodeled and added three light fixtures to our staircase. The top one is a recessed can to light the top steps. About halfway down is a pendant, hung 10' above the tread beneath it. Near the bottom is a matching pendant, hung again at 10 feet above the tread below. This set of lights lights the stairs evenly with few shadows -- a safety as well as aesthetic consideration. Can you add two or three lights instead of just one? If you are hanging only one, will it be about halfway down? If so, it should probably hang slightly above the eye height at the top of the stairs.

What did you tie them to? I have two small screws on the side of our posts where the actual lamp attaches. So I use two twisties that I bring around the post and then tie to the screws on either side. It gets very windy here too but that's always held them in place.

Wondering what the correct height is to hang pendants and chandeliers? Our Austin studio's principal designer shares useful tips: