Harold Kestenholz
Another method of zoning so each and every room is a separate circuit is to use a one-pipe circuit.
http://64.226.150.132/hydronic/onepipe/index.htm
As an alternative, it is possible to use one supply pipe and one return pipe with one supply riser from the supply and one return drop to the return pipe to each piece of radiation. This is usually done as a reverse return system for commercial buildings.
