Rhoddys really respond well to a strong prunning. After the plant is done blooming, you are safe to prune it, and can remove up to 1/3 of the plant with good results. It will bloom more for you as well. Good luck.

Thank you Laurie. I've seen so many tall beautiful Rhoddys and couldn't figure out why ours was so small.

There are hundreds, if not thousands, of Rhododendrons: species, hybrids and cultivars. Unless you know your neighbours have exactly the same plant comparisons are not meaningful. Apart from which yours might just be younger.