The height of the lamp is not as important as where the light shines. In a bedroom, the light must be functional and should also be beautiful.
A bit of thought and planning to determine what lamps are necessary will lead directly to measuring with confidence, resulting in the correct height of the lamp.
Lamps on bedside tables should be tall enough that the bottom of the lampshade is level with the shoulders of someone sitting up in the bed, resting against the headboard. This provides optimum light for reading.
The height of the bed and the height of the bedside table affect the height of the bedside lamp. Wall lamps used as bedside lights should follow this guideline as well.
Lamps Beside Chairs
If the primary function of the chair is reading or handcrafts, a down-directional floor lamp should be tall enough that the bottom of the shade is level with the shoulder of someone sitting in the chair. A lamp on a table beside a reading chair should follow the same guidelines.
Wall sconces, used as mood or ambient lighting, should be placed on the wall so that the light bulb is not visible to the tallest member of the household. Down-directional sconces should be positioned with the top of the sconce at about 60 inches -- more on tall walls, less on short walls.
Freestanding table lamps for tall-boy dressers and chests of drawers should be of a height that is in proportion to the piece of furniture. If there are mirrors above the pieces used for dressing, the lights should be tall enough that the bottom of the shade is above eye level.
Down-directional table lights on vanities should be tall enough that the bottom of the shade is above the eye level of a seated person. For the best, balanced lighting, vanities should have track lights above that are down-directional and lights at each side.
Wall sconces for vanities should be placed above eye level.
After planning the lighting requirements of a bedroom, it is useful to take the plan, along with a sketch of the floor plan of the room, to a lighting store. Ask the resident designer for assistance in choosing the wattage of lights to place at each position.