пристройка bedeutet auf Englisch

annex [annexes]▼(addition or extension to a building)
noun
[UK: ˈæ.neks] [US: ˈæ.ˌneks]

expansion [expansions]▼(new addition)
noun
[UK: ɪk.ˈspæn.ʃn̩] [US: ɪk.ˈspæn.ʃn̩]

granny flat▼(dwelling detached from a main residence)
noun

outbuilding [outbuildings]▼(separate building associated with a main building)
noun
[UK: ˈaʊt.bɪld.ɪŋ] [US: ˈaʊt.bɪld.ɪŋ]

penthouse [penthouses]▼(an outhouse or other structure attached to the outside wall of a building)
noun
[UK: ˈpent.haʊs] [US: ˈpent.ˌhɑːws]