Besides the advantage of air heating (that gives the illusion of reheating the house [1])there are a lot of differences in the way houses are built. Generally

Besides the advantage of air heating (that gives the illusion of reheating the house [1])there are a lot of differences in the way houses are built. Generally speaking "traditional" houses in Europe (made with brick or stone walls) tend to have rather poor insulation but very high termal mass, as opposed to more modern houses (and to the essentially wood/timber based houses in north America) that have a higher insulation but very low thermal mass. In high thermal mass houses completely changing the air does not lower that much the temperature as as soon as you re-close the windows the air is re-heated by walls, ceilings and floor radiating the heat they accumulated before. [1] whilst in reality it only re-heats the air