Construction element , in particular for domestic use, which extends along a longitudinal extension direction (L), comprising a body , a lid and a cooling section , wherein the body extends in the longitudinal extension direction (L) and together with the lid encloses an interior space at least in part, the lid being designed such that the combustion gases of a fireplace are guided directly or indirectly through it, the cooling section being arranged on a first outer surface of a first wall of the body wherein the inner region of the cooling section is to be formed by the intermediate space between a structural wall (B) and the said first outer surface , wherein the cooling section comprises a partition wall , an inlet opening and an outlet opening , wherein the inlet opening is designed to allow air from the environment (U) to pass indirectly or directly through it into the cooling section , wherein the at least one outlet opening is designed to connect the environment (U) indirectly or directly to the inner region of the cooling section , wherein the inlet opening is arranged below the outlet opening , the element enclosing the fireplace at least in certain regions, wherein the fireplace can be introduced into the interior space through a feed opening , the inlet opening connecting the cooling section to the interior space in a fluid-conducting manner, and the feed opening connecting the interior space to the environment (U) in a fluid-conducting manner, characterised in that the partition wall has a contact surface which is adapted to be arranged on a structural wall (B) in order to delimit the inner region of the cooling section from the environment (U), and in that the ratio of the minimum distance of the inlet opening to the outlet opening to the total length of the element in the longitudinal extension direction (L) lies in a range of 0.4 - 0.9, wherein the construction element is designed for a fireplace independent of room air. comprising a body , a lid and a cooling section , wherein the body extends in the longitudinal extension direction (L) and together with the lid encloses an interior space at least in part, the lid being designed such that the combustion gases of a fireplace are guided directly or indirectly through it, the cooling section being arranged on a first outer surface of a first wall of the body wherein the inner region of the cooling section is to be formed by the intermediate space between a structural wall (B) and the said first outer surface , wherein the cooling section comprises a partition wall , an inlet opening and an outlet opening , wherein the inlet opening is designed to allow air from the environment (U) to pass indirectly or directly through it into the cooling section , wherein the at least one outlet opening is designed to connect the environment (U) indirectly or directly to the inner region of the cooling section , wherein the inlet opening is arranged below the outlet opening , the element enclosing the fireplace at least in certain regions, wherein the fireplace can be introduced into the interior space through a feed opening , the inlet opening connecting the cooling section to the interior space in a fluid-conducting manner, and the feed opening connecting the interior space to the environment (U) in a fluid-conducting manner, characterised in that the partition wall has a contact surface which is adapted to be arranged on a structural wall (B) in order to delimit the inner region of the cooling section from the environment (U), and in that the ratio of the minimum distance of the inlet opening to the outlet opening to the total length of the element in the longitudinal extension direction (L) lies in a range of 0.4 - 0.9, wherein the construction element is designed for a fireplace independent of room air. <EOS>