There are two types of underfloor heating. the pipes one is run like central heating and uses a boiler. These tend to be thicker and installation costs are higher than electric. Electric underfloor heating is a doddle to lay down, they're available in different sized mats, but you need an electrician to hook it up. Installation costs a lower but slightly higher running costs (I've been told).
We used electric underfloor heating throughout the house and it's great. we have it under engineered floorboards, under carpets and under tiles.