Thermostat linking for automation.

Good morning. I am wondering about a Rule being built into your thermostats. I need a rule that if 1 starts heat it will trigger the other into heat regardless of the temp of the slave thermostat. I need either one to be the master depending on the the temperature of that end of the area.

I have a large area with 2 radiant zones, one on each end. The valve controller is a Taco ZVC-405. It will not allow me to jumper from one zone to the next hence the 2 stats in that area. I understand I could accomplish this with a sensor and several relays but it could also be accomplished with a Rule. Other automated companies have already been doing this kind of thing so I was wondering if you were able to also.
Thank you Scott