35-how to select duct sheet thickness & gage as per SMACNA, duct sheet gauge calculation, eng. nasir 

Please watch this updated video, then write if you have any doubt. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-PeEilQztW2E.htmlfeature=shared

Thanks, it part 4 ,I will up load ESP calculation as part 6, then I will arrange to share some folder with these tables, I have one old video for ESP calculation but I will upload new videos for it that is updated and more clear. Link for old video ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-cStb7V9HuP8.html

Thanks sir

It is general practice as normally GI sheet available in this size.