90 degree joint for lean-to roof joist

[XTiffy]

The caps came without nails or screws. I chose to use green outdoor screws which are available in various lengths. The caps are in two parts held together with a small plastic extrusion (so caps do not get lost,) this is helpful as sometimes in the summer the cap can pop up with expansion.
I used a regular HSS drill but that idea of a masonary bit must have been meant for concrete sheets, for plastic sheets the wood bits would be ok.

 

[Chris152]

The caps came without nails or screws. I chose to use green outdoor screws which are available in various lengths. The caps are in two parts held together with a small plastic extrusion (so caps do not get lost,) this is helpful as sometimes in the summer the cap can pop up with expansion.
I used a regular HSS drill but that idea of a masonary bit must have been meant for concrete sheets, for plastic sheets the wood bits would be ok.

OK, that's great - thank you!

 

[XTiffy]

Chris 152,
I can't emphasize enough not to wind screws in too far, with plastic or unduline sheets it is easy to flatten or spread the sheet which messes up the meshing of adjacent sheets. As the screws go in at the crest, rain immediately flows down into the valleys, so a small"pinch" is all you need.

 

[Fergie 307]

I use these from seller eighty-twenty on e bay. They take size 8/10 screws. I much prefer using screws rather than nails especially on the clear sheets, they are quite brittle.