Garage roof

[rich22]

Hi
Just a few questions on doing my garage roof
its a flat roof. The garage is between us and next doors,sandwiched between to bungallows with a solid brick wall at the back a wall down the centre witch splits the two garages. If your looking from the front the garage door frame is attached to the bungallow then 2.2m door with 300mm of brick work,then next doors doors is the same in reverse 300mm brick work and so on,the garage is 4.8m front to back.
1. If i put a 50mmx 100mm timber on the bungallow wall using coach screws or something simler with a fall from front to back, then build a brick pillar half way along the centre wall,then put a length of 50mm x100mm from the front pillar to the back wall and it will sit on the new pillar, then using joist hangers put the joist at 600mm centres using 50mmx100mm.The reson for going across and not front to back is head room.Does this sound ok i will be doing next doors at the same time.
2.Witch bording is best i am going to be using EPDM rubber.
Thanks for reading all of this i hope someone can help.

 

[rich22]

Is there something wrong with what i am asking?

 

[SASroofer]

Its a bit hard to picture all of the above in my mind mate, get a few pics uploaded, and you will see a lot more interest

 

[^woody^]

I can't see the relevance of the new brick pier, or the timber going from front to back on the centre wall

4x2 at 600 centres seem a bit flimsy

You want a minimum 18mm board in either WBP ply or OSB grade 3

Why aren't you just putting the joists level across to two properties and using furrings to form the fall?

 

[rich22]

Thanks woody so will it help if i go to 400 centres on the 4x2 or will i have to go for 6x2.The reason for not doing the timbers level across the two properties is because the back wall is lower so the fall is there and next doors property is lower so at the front corner there is only about 6 inches from the top of the flat roof to the underneath of th soffit,so no room to increass the hight.The brick piers are there to divide it into 2.4m sections because the width from one property to the othere is 5.2m,so minuss the 100mm each side for the timber on the each propery i am left with 5.0m, isnt the max timber length 4.8m.