Is Underfloor Heating Unhealthy?

No underfloor heating is not unhealthy: underfloor heating is much healthier to have in your home than radiators as the whole floor acts as an emitter for radiated heat rather than radiators which acts as convectors to heat the air in a cycle which kicks up dust and circulates it around the room.

Safer Than Radiators 

Underfloor heating is also safer than radiators, this is especially true when talking about vulnerable people like children or the elderly. Radiators have to get very hot to be able to heat rooms and this creates very hot surfaces which present a burning hazard. Underfloor heating does not get as hot as radiators and the hot surface is not exposed meaning the risk of burning with underfloor heating is zero.