quote" Guys I am thinking the bill wants decking material to go on top of the rafters thick enough so the roofing nails don't show from underneath thus the open porch ceiling thing with the rafters showing. "quote

I think this is exactly what he's asking for.

When I build cathedral ceiling cabana's and pavilions for my pools I use T111 turned upside down for the price conscious buyers or 116 pattern V-groove cedar or #1 pine then stain/seal it when price isn't really the issue.

Here are some pic's, during construction, of the pavilion by my pool. When they get really large I stop the standard hip/ridge/jacks/common rafters with decking going left to right and use hip/ridge/mini beams from hip to hip across a common and run the decking up and down.
This 116 pattern is a 1x6 tongue and groove. Using a 7/8" roofing nail it doesn't come through. It doesn't come through on 5/8" T111 when using an architectural shingle, with a 3 tab shingle on T111 it slightly pokes the nail tip out.

John you and the other deck guys here do some AWESOME work!!! The members of this forum are very fortunate to have industry pro's like yourselves contributing their insight. I'm thankful for the tips and design ideas I've learned from you guys surfing while this forum.

See ya,
Kelly