Abstract: A steel building having a frame with at least one roof beam on respective top sides of the frame wherein the top ends of the roof beams defines an apex, at least one side wall post and an eave strut member along the outer edge of the roof at the side wall posts being generally square and tubular in construction, having a hollow interior, an open face in which flanges on respective sides are directed inwardly, being insulated by inserting an insertion means into the hollow interior and a barrier wrap around the strut member between each of the side posts. A kit of parts for the building comprising an insertion means at the inner portion and a barrier wrap surround the strut member between each of the side posts.