Following are a number of back-translations as well as a sample translation for translators of Job 27:18:

• Kupsabiny: “(They) are building a house like that of a spider,
  or like a shelter of/for people who guard the fields.” (Source: Kupsabiny Back Translation)
• Newari: “The house that he builds will be as weak as a spider web,
  or will be like a shelter built by one who stays [there as a] watchman.” (Source: Newari Back Translation)
• Hiligaynon: “The house he builds is as fragile as the web of a spider or a hut of a watchman in the field.” (Source: Hiligaynon Back Translation)
• English: “The houses that they build are as frail/fragile as spider webs,
  or they are like flimsy huts that watchmen live in while they guard people’s fields.” (Source: Translation for Translators)