roof

Not sure if I'm using the right stuff or if im using it just incorrect but doesnt look like its going stay. Any tips or tricks to secure these conduit mounts. I'm guessing i just need to clean the surface better and use more? I reckon im better off using that black double side industrial tape.

Has anyone had experience using a roof ridge ladder hook, like this one? There's a rather steep section of my roof that I need to access and I am trying to avoid renting some kind of lift/boom. Thanks!