From Longman Dictionary of Contemporary Englishunappealingun‧ap‧peal‧ing /ˌʌnəˈpiːlɪŋ◂/ adjective UNPLEASANTnot pleasant or attractive an unappealing shade of grey
Examples from the Corpus
unappealing• There was an unappealing gloom inside and he could just make out the empty pews enclosed by wood panelling.