Canopy roof timbers

[gaz_moose]

I want to build a canopy roof like attached.

Ive only ever done flat roofs and this will be tiled with marley double roman concrete.

width will be 9.5m 

 

How do i calculate what size timbers to use? 

Does my paintshop plan look like how they are built?

I intend to put gallow brackets at either end and in the centre. ( the house is like you would draw as a kid with 4 windows and the door in the centre) so i was going to put 2 gallows either side of the door so 4 gallow brackets in total.

 

MY brain says to use 2x4 c16 for everything except the facia board which would be 1". But i dont want the facia boards to be massive so can i use smaller timber?

 

 

[Russell griffiths]

Sort of but not entirely right. 
your terminology is a bit wrong. 
the joist in red is a rafter.

horizontal in blue is a joist 

so red one rafter needs a seat cut at the bottom to either sit on top of the blue one (joist) or fix it to the side of the blue one. 
this will lower your facia height. 
i would also look for a different tile, the double romans are a pain to get the ends looking neat, they also look too big on a small roof. 
go for a small concrete tile.