Due to this source of wasted water and the significant potential in energy and resource savings in preventing it, a growing number of building codes are requiring hot water recirculation or pipe heating (such as electrical tape) to conserve water.
We were talking about early heating systems, Ara and I. I had questions and he had answers. When you want to know stuff about how things began, it pays to ask someone who has been dead for a while. Guys like that were there at the start and saw most of it for themselves.