In buildings energy is needed for operating the building, particularly for  Cloze (1): JXUwMDJiJXUwMDAzJXUwMDExJXUwMDAyJXUwMDA2JXUwMDQ1JXUwMDQ4JXUwMDBkJXUwMDA0JXUw MDE1JXUwMDFkJXUwMDA3JXUwMDA5 ,  Cloze (2): JXUwMDMwJXUwMDA3JXUwMDFiJXUwMDU0JXUwMDU3JXUwMDE2JXUwMDE1JXUwMDExJXUwMDE3 and  Cloze (3): JXUwMDM0JXUwMDA1JXUwMDBlJXUwMDBmJXUwMDFjJXUwMDFkJXUwMDA3JXUwMDA5 . But not only these services need energy; the actual process of construction, any reconstruction or renovation, the demolition of a building, and the production of building materials all consume energy (this is called "grey energy", because how much energy a material or product contains is not visible to the naked eye).

There are various different ways of reducing the resource and energy consumption of buildings.

A high level of  Cloze (1): JXUwMDJjJXUwMDFjJXUwMDBkJXUwMDE3JXUwMDFmJXUwMDBjJXUwMDBkJXUwMDRjJXUwMDQ5JXUw MDA3JXUwMDFkJXUwMDA2JXUwMDE5JXUwMDBkJXUwMDE1JXUwMDFkJXUwMDA2JXUwMDAx of the building envelope is an effective measure. As part of this, installing Cloze (2): JXUwMDNkJXUwMDBiJXUwMDBiJXUwMDE3JXUwMDE1JXUwMDFlJXUwMDU0JXUwMDQ4JXUwMDAzJXUw MDAwJXUwMDBmJXUwMDBhJXUwMDBhJXUwMDBjJXUwMDBiJXUwMDFhJXUwMDU0JXUwMDU3JXUwMDFl JXUwMDA3JXUwMDBhJXUwMDBiJXUwMDE4JXUwMDA0 is important. An additional measure for reducing heat losses by airing is to install a  Cloze (3): JXUwMDNiJXUwMDBjJXUwMDAxJXUwMDE4JXUwMDEzJXUwMDBiJXUwMDA3JXUwMDBjJXUwMDBiJXUw MDBkJXUwMDA2JXUwMDQ1JXUwMDU2JXUwMDEzJXUwMDBiJXUwMDFhJXUwMDFkJXUwMDA1JXUwMDBk JXUwMDE1JXUwMDFkJXUwMDA2JXUwMDAxJXUwMDRlJXUwMDUzJXUwMDBhJXUwMDBhJXUwMDA3JXUw MDExJXUwMDA4JXUwMDRkJXUwMDU3JXUwMDFlJXUwMDFkJXUwMDFjJXUwMDQ4JXUwMDQ4JXUwMDBk JXUwMDA0JXUwMDE1JXUwMDU0JXUwMDUyJXUwMDE3JXUwMDA2JXUwMDBjJXUwMDE5JXUwMDEzJXUw MDE3JXUwMDBi . The consumption of electricity can be reduced by using  Cloze (4): JXUwMDNkJXUwMDBiJXUwMDBiJXUwMDE3JXUwMDE1JXUwMDFlJXUwMDU0JXUwMDVlJXUwMDEyJXUw MDE3JXUwMDFmJXUwMDA3JXUwMDA5JXUwMDQ3JXUwMDQ0JXUwMDAxJXUwMDEzJXUwMDFmJXUwMDBh JXUwMDA2JXUwMDE2 ; the input of grey energy can be influenced by choosing appropriate  Cloze (5): JXUwMDNhJXUwMDE3JXUwMDFjJXUwMDA1JXUwMDA4JXUwMDBkJXUwMDA3JXUwMDA5JXUwMDQ3JXUw MDRkJXUwMDBjJXUwMDE1JXUwMDExJXUwMDE3JXUwMDFiJXUwMDA4JXUwMDBkJXUwMDFm .