Can I put my sofa and other large furniture items on a floor with UFH? 

It is perfectly okay to put furniture on a floor with UFH as long as the furniture allows some airflow at floor level (i.e. has castors or feet). Any furniture with a large/flat “footprint” such as a filing cabinet with no feet, or a futon style bed that sits directly on the floor, will cause thermal blocking and should not have UFH below it. Similarly – beanbags placed in a room with UFH will cause a “thermal block” and will compromise the efficiency of the system.