If you have radiators in the rest of the house then it is no problem to connect underfloor heating to the existing system. There are various ways to solve this depending on the size of the room.
It is not difficult, and is largely about finding an underfloor heating system that is suitable for your floor construction and a mixing unit (referred to as a shunt group below) to connect it to the existing system.
If you need more information then you can read our detailed assembly instructions at "Technical documentation". If you cannot find a suitable construction, or are unsure about your choice, then you are always welcome to contact our customer support for expert advice.