Hello,
My flat roof (over the car port) has started leaking so I thought it might be better to replace the flat roof with sloping plastic sheeting like this:
I assumed that I would run some rafters parallel with the sheets but the instructions say that actually I should use purlins perpendicular to the sheets. I am puzzled by this. My way seems easier because I have a wall at each end to attach the timber to. What am I supposed to fix the purlins to?
The instructions are vague about the pitch. It seems you can use anything from 5 degrees upwards. is there an optimum angle?
Do you have any other tips or advice?
Thanks, Stephen.