article_snippet.sent: A small scale trial is also underway to test how the heat can warm up different types of stone floors in the buildings.
article_snippet.sent: the Romans came up with underfloor heating called a hypocaust, which heated houses and public spaces with hot air.
article_snippet.sent: The word comes from the Ancient Greek, where hypo means under and caust means burnt.
article_snippet.sent: the Romans used underfloor heating, or hypocausts to heat rooms at Bath's intricate bathing complex.
article_snippet.sent: Here, you can see the pilae stacks though which hot air would have circulated to heat a tile floor on top .
article_snippet.sent: a tile floor was raised above the ground by pillars called pilae stacks and made of a layers of tiles sandwiched together with concrete.
article_snippet.sent: The air under a tile floor was heated by a furnace.
article_snippet.sent: Walls were also made of hollow bricks so hot air could circulate through Walls, as well as below the tiles.
article_snippet.sent: Rooms requiring the most heat were placed closest to a furnace, the heat of which could be adjusted by adding more wood to the fire.
article_snippet.sent: It was labour intensive to sun a hypocaust as the fire needed a lot of fuel and constant attention, meaning underfloor heating was used in large public buildings, luxurious villas and bath complexes.