A lot of people decide to build energy- efficient house. Therefore, the expectations of customers come architectural offices which offer projects of such houses. These houses at first glance do not differ from standard proposition, but these projects included the use of such materials and products, which can reduce to the minimum a heat loss. It is possible thanks to the special coatings, sealing materials and doors and windows with high, good parameters. In energy efficient houses are also assembling a special ventilation systems and sometimes it is also contain in the house design.