Fixing CGI (Corrugated galvanized Iron) sheet roofing : 

1. The length and gauge thickness of the sheet should be checked as per the specification before spreading the CGI sheet.
2. The overlapping side length should be at least 150 mm or 2.5 corrugation.
3. When tying the CGI sheet with purlin, at least 3 J-hooks should be pressed to the width of one sheet.
4. When drilling holes for J-hooks, only the upper part of the corrugation should be drilled.
5. The length of the hook portion should be equal to the outer diameter of the precision measured purlin.
6. Each J-hooks should have two bitumen washers and 1 cup washer.
7. The truss should be painted anti corrosion paint.
8. When the J-hook is tightened, the tip of the hook should be turned towards the axis to hold the purlin and the long section of the threaded J-hook should be shifted towards the lower slope to prevent the CGI sheet falling down.

Please click the link below for information about Corrugated roofing sheets  :

https://www.roofingmegastore.co.uk/roofing-categories/pitched-roofing/corugated-roof-sheets.html.

Please click the link below for demo video :

https://www.youtube.com/watch?v=xrhhgzqL_z4

Click the link below for the assignment.

https://docs.google.com/forms/d/17UWL5q9nFF58O80_ru1JriDKrfn6COdmPAy7dVRjcvw/edit