Many different ways, examples include:
electric furnace
heat pump
gas furnace
kerosene furnace
wood stoves
boiler setups
passive solar
and the list goes on.
It is heated by the the fire
When matter is heated it will expand
Most people like their houses heated to about 68 Fahrenheit, 20 Celsius, but we are being encouraged to lower the temperature by a degree or more to lower our heating bills and reduce carbon emissions.
It means something that is heated by the sun or left out in the sun to dry.
When a solid is heated it expands and if is heated enough it will melt; it may also boil. If you cool it down it will go back to solid form.
Roman houses were heated by central heating
The sweat house were heated with fire.
They are heated using Geothermal Energy.
geothermal energy
Is it Iceland?
maybe
The Roman baths were a cultural custom and their presence evolved over a period of time. It is not known when the baths were developed nor who "invented" them. When we read about the Roman baths, even the very early ones, they are already developed into the form (hot, warm, and cold rooms) with which we are familiar.
Afghan houses are very cold in winter. Wood fires don't provide a lot of heat, and there is little wood.
It is Iceland that has geothermal vents. Iceland's population use it to heat their houses and to make electricity.B.C. The Hairless Guy
Margaret F. Fels has written: 'PRISM: A Conservation Scorekeeping Method Applied to Electrically Heated Houses'
Neolithic houses were made of varying materials depending on the region. For example, houses in the British Isles were often made of mud and woven twigs. The thatched roof had a hole left in it for smoke to escape as they cooked and heated indoors with fire. In other locations, mud bricks or combinations of mud and stones were used.
It can be a problem in any house that uses natural gas, fuel oil, propane, or a fireplace. Basically if anything is heated with a flame you could have carbon monoxide.