Wide windows on the south side of the building
The windows in the energy efficient house should never reach from floor to ceiling, because it causes heat loss. The windows of this type tend to be planned only on the south side, where the plentiful sunshine makes the heat losses are not large.
However, in energy- efficient houses very important is not only heat but also the energy consumption. Because of this all windows in such buildings are large but they are usually wide and not long. The exception could be windows of the southern side of the house, where it is permitted if they do not represent the whole of the building walls.