In modern architecture cantilevered stairs set new standards. The tread steps of cantilevered stairs seem to jut out freely from the wall which results in a highly impressive effect. There is also a supporting structure needed for cantilevered stairs: a stair stringer with welded-on steel treads embedded in the wall. The bearing steel steps are encased by the tread steps. This kind of construction can be completed with wooden, marble or granite steps. The bearing steel treads, constructed as box-type treads, are filled with a footfall sound insulation.