I am looking for a good German term for a building which has only a ground floor. I found the suggestion Bungalow, but this word seems not very descriptive to me. Is eingeschossig or einstöckig a correct term for such a building?
Compounds with eingeschossig or einstöckig and Haus or Gebäude work well.
A Bungalow is usually used to refer to a residential building or a cottage. If you want to refer to an industrial building, you can also use the word Flachbau.
Bungalow is sometimes used with the intended meaning, but it’s not well understood that way. For instance, a vacation home described as Bungalow used to mean a simple solitary building with just one floor, but nowadays many multi-room, single-storey apartments will also be labeled that way.
Wikipedia mentions Baracke ‘shack, shed’ – English barracks translates to Kaserne – had also a single floor, but that term cannot be used generically for such buildings, because it has a derogatory connotation.
There’s a special kind of older buildings in rural parts of Germany called Kate or Kotten. They usually have just a ground floor, but – unlike many bungalows – they have pointed roofs, so there may be living space in the attic, which may have been converted recently. Anyhow, if you want to stress the fact of a single floor this word (and its many dialectal variants) will not work reliably either.
The adjectives eingeschossig and einstöckig work perfectly well. You’d use Haus (or a compound thereof, e.g. Wohnhaus) ‘house’ or Gebäude ‘building’ with them most of the time. Like English single-stor(e)y and single-floor(ed) they are derived from relevant nouns das Geschoss and der Stock or das Stockwerk. There’s another synonym, gallicism die Etage and hence einetagig /…etaʒik/ is also possible, although it’s not yet listed at dict.cc for instance.
While Stock(werk) and Etage are numbered, e.g. in lifts, Geschoss is the preferred one for compounds: Erdgeschoss (EG) ‘ground-floor’, Untergeschoss (UG) or Kellergeschoss (KG) ‘basement’, Dachgeschoss (DG) ‘attic’ and n-th Obergeschoss (OG) ‘upper floor’. Note that sometimes “1. OG” = “2. Etage” = “2. Stock”, but elsewhere “OG” = “(Etage/Stockwerk) 1” and “EG” = “0” (cardinal, less often ordinal with dot). That means, floor numbering is ambiguous except with “OG” (and “UG”/“KG”). The mentioned Wikipedia article currently even claims that otherwise synonymous Stock and Etage correlate differently with numbering conventions: “1. Stock” = “2. Etage”.
There’s also Parterre, a French loan word for Erdgeschoss, but neither can really be used to form a compound or derive an adjective that would denote a single-storey house: *Nurparterrehaus.