Best way is to build a frame first here's an example how I started my workshop use small ladders to get up higher craft a few ontop of each other then destroy.
There is lots of different methods but always try for a frame first then add the correct roofing and you wont have any deteriation.
https://steamcommunity.com/sharedfiles/filedetails/?id=2417628896
finished results
https://steamcommunity.com/sharedfiles/filedetails/?id=2609239264