Installation - Fixings
All sheet edges and edges in openings should be sealed before sheets are fixed. All joints must be made on a stud or fixing batten. Care must be taken with edge detailing.
Simple butt joints that rely on flexible mastic for sealing may break down prematurely. This means they will allow water into the edge of the sheet or the frame of the structure. A more reliable butt joint can be made using a cover batten over the sheet joints with the interspace filled with mastic. An alternative method is to use a pre-formed metal or plastic joint cover section with a mastic sealant.
Horizontal joints between sheets should be flashed or rebated.
Fixings should be in accordance with manufacturers' recommendations and to best industry practice.