Dormer Cheeks, that are within 1m of a relevant boundary, will need to provide fire resistance from both the internal and the external side of the wall. Promat SUPALUX® is recommended for this application.  Please note that SUPALUX® is suitable for semi-exposed locations, such as soffits, but boards must be protected from direct weathering in this application, by use of an external grade cladding board/system. SUPALUX® can not be directly rendered, so a suitable carrier board would be needed if a render finish is required. 

Please download the appropriate document below for the full specification. 

TDS054 - 30 minute SUPALUX® Dormer Cheek
 

TDS086 - 60 minute SUPALUX® Dormer Cheek

Please be aware that we do not have any tests or certification on this type of construction and this solution is given as a Promat suggestion based on our experience, in house knowledge and extensive testing of our products. Approval to proceed on this basis must be obtained from a third party such as the project fire engineer or building control officer responsible for the project. All parties will need to take this into consideration prior to the commencement of construction.