Installation of underfloor heating in the upper floor hallway area

Hello everyone,

as you can see from the attachment, we are currently installing the underfloor heating. We are not entirely sure about the next steps for the hallway on the upper floor, so here is the following explanation: The HKV is located in the master bedroom behind the door. From there, the supply and return lines each lead into the children's room. If I do not lay the underfloor heating from the bathroom through the wall into the HKV (which was still possible), a third supply and return line would run through the hallway. Having a separate heating circuit for the hallway would be correspondingly small, as the pipes to the adjacent rooms already take up quite a bit of space. In addition, the hallway on the ground floor is of course also heated. Therefore, I am wondering how the hallway on the upper floor can be controlled at all, since it is actually an open space from the ground floor to the upper floor. I have planned KNX with appropriate control via temperature sensors.

Should I simply omit the separate circuit for the hallway, since it is warmed from below anyway and the supply and return lines also heat the hallway somewhat, or should I install a separate circuit? Or will the floor become too cold in areas where there are no supply and return lines? If I do install a small heating circuit, how does the control work? In theory, the two hallways would then "work against each other."

Thanks for your answers and best regards!

Therefore, I wonder how the hallway on the upper floor can be controlled at all, since it is actually an open space from the ground floor to the upper floor. I have planned with appropriate control via temperature sensors.

A underfloor heating is not "controlled". It is calculated, installed, and set. Save your KNX money and rather invest in professional underfloor heating planning.

Should I simply omit the separate circuit for the hallway since it will be warm from below anyway and the supply and return pipes also slightly heat the hallway, or should I install a separate circuit?

The planning will tell you that.

Or will the floor get too cold where no supply and return pipes run?

Cold is relative. A floor with today's underfloor heating systems and low supply temperatures won't get warm anyway.

A floor heating system is not "controlled." It is calculated, installed, and adjusted. Save your KNX coins and rather invest in professional floor heating planning.

It is now planned this way and will remain so; it is controlled via the temperature sensor. I have a plan that provides for a single circuit. However, I cannot implement it this way because of the supply and return lines, as I no longer have the space.
Therefore, I now have to decide what to do.

It is now planned this way and will remain so, it is controlled by the temperature sensor.

OK - it’s your money and no further discussion that the sensors will get bored.

That’s why I have to decide now what I’ll do.

All circles through the hallway, if necessary with a swirly, so that you cover the area evenly.

All circles through the hallway, possibly with a flourish, so that you cover the area evenly.

Ok, is it disadvantageous here to route the bathroom loop with flourishes through the hallway? After all, the bathroom is the warmest room, and if I already lose some from the supply line in the hallway, it might not be favorable?

Ok, is it disadvantageous here to lay the bathroom circuit with loops through the hallway? After all, the bathroom is the warmest room, and if I already lose some heat in the hallway from the supply line, maybe that's not ideal?

First of all, you lose a meter or two. That is negligible. Otherwise, you have a calculation that can be adjusted if a lot of heat is to be emitted in the bathroom. What is the exact design? Just post the data and the actual laying plan. Then more can be said.