I have to heating issues to take care of at the opposite end of my house from my boiler and manifold. I have an open 180 degree space in my main manifold and need to two heat seperate zones at the other end of the house. My thought is to run Pex Al Pex to the other end of the house from a pump in main manifold then mount a manifold with two hot and returns creating a loop off from the main manifold. On the new manifold would place two zone valves to run to either a panel heater or kick space heater in a bath room and the other would be to a panel on second story (basically 11-12 feet above the zone valve). I don't have any Pex Al Pex tools so I decided to call my original plumber. He is pricey but did a great job on original setup which includes radiant and fin tube.
I have those blessed open engineered floor joists that have an "X' pattern to them with lots of space to run pipes. My plumber says he can tuck the new manifold and zone valves up in the basement ceiling. Any one ever do that before? I don't have an pictures of the floor joists. Must be 10 or 12 inches of max space to use there. Any thoughts or problems or issues to watch out for? I'm no sure how he plans to mount every thing yet. I have a Taco relay control with enough open space (I think) or could just get another one if needed so not to worried about controls at this point.