Heating device

The present invention relates to a heating device for heating an annular joint area between a tubular tower segment with a circumferential segment wall and a tower foundation of a wind energy installation during assembly of the wind energy installation. The heating device comprises one or more covering tarpaulins for covering the joint area and one or more annular support frames for supporting the or one of the covering tarpaulins, wherein between the joint area and the covering tarpaulin there is sufficient space for at least one adult person. Furthermore, the invention relates to a method for erecting a tower of a wind energy installation.