A ‘check reveal’ is a detail that is particularly common in Scotland and Central Europe and involves an opening being formed in the external masonry skin where the external structural opening is smaller than the window frame and consequently the external face of the window frame when installed butts up against the back of the external skin.

In this scenario the primary weather seal is formed between the front face of the window and the opening rather than the outer perimeter of the window and a conventional ‘flush’ reveal. The check reveal undoubtedly therefore produces a more protected joint and impregnated foam tapes are ideal for providing an external weather seal in such details.

It is important however not to overlook the potential for thermal bridging between the window frame and the structure and appropriate insulation should be incorporated in this joint which again can be provided by impregnated foam tapes.