A balcony for attachment to a building wall having: - a balcony floor construction having a balcony floor top side and a balcony floor underside, - a carrier profile frame made of carrier profiles (12, 14, 16, 18), forming a balcony floor covering for sections of the balcony floor underside, and - a holding system fixing the carrier profile frame, for attaching the balcony to a building wall wherein the balcony floor construction has a balcony floor structure constructed of at least two cassette elements extending along a common extension direction, wherein each cassette element seen in the cross-section perpendicular to the extension direction is shaped in such a manner, - that it has a basis which forms a part of the balcony floor underside and - that at least one coupling leg having a coupling area spaced apart from the base, for connecting neighboring cassette elements and/or for applying a balcony floor cloth on the balcony floor structure extends starting from the base, wherein each coupling area has a positive fit section extending along the extension direction, by which neighboring cassette elements are connected to each other by positive fit, wherein the cassette elements, the carrier profile (12, 14, 16, 18) or both are made of beveled thin sheet, and between base and coupling leg of the cassette elements a coupling leg angle A of 60 to 70 degrees is formed, respectively, wherein the positive fit section of each coupling leg has a first positive fit section (701, 711) extending parallel to the base of the cassette element and wherein subsequent to the first positive fit section (701, 711) a second positive fit section (702, 712) extending in angled or curved manner away from the first positive fit section (701, 711) is formed. - a balcony floor construction having a balcony floor top side and a balcony floor underside, - a carrier profile frame made of carrier profiles (12, 14, 16, 18), forming a balcony floor covering for sections of the balcony floor underside, and - a holding system fixing the carrier profile frame, for attaching the balcony to a building wall wherein the balcony floor construction has a balcony floor structure constructed of at least two cassette elements extending along a common extension direction, wherein each cassette element seen in the cross-section perpendicular to the extension direction is shaped in such a manner, - that it has a basis which forms a part of the balcony floor underside and - that at least one coupling leg having a coupling area spaced apart from the base, for connecting neighboring cassette elements and/or for applying a balcony floor cloth on the balcony floor structure extends starting from the base, wherein each coupling area has a positive fit section extending along the extension direction, by which neighboring cassette elements are connected to each other by positive fit, wherein the cassette elements, the carrier profile (12, 14, 16, 18) or both are made of beveled thin sheet, and between base and coupling leg of the cassette elements a coupling leg angle A of 60 to 70 degrees is formed, respectively, wherein the positive fit section of each coupling leg has a first positive fit section (701, 711) extending parallel to the base of the cassette element and wherein subsequent to the first positive fit section (701, 711) a second positive fit section (702, 712) extending in angled or curved manner away from the first positive fit section (701, 711) is formed.