Boiler flue distances

Robbo29777

Hello everyone! I have a question I have a recently built a pergola at the back or my property. I have now however been instructed by my wife to put a roof on it so she can be protected from the elements whilst in the lazy spa underneath. 

However I have a horizontal boiler flue that sticks out directly underneath the pergola and therefore I am after some advice about distances in which the flue can and cannot be covered. 

The flue itself is far enough away from the rafters as to not be effected by temperature or moisture. However how far away must the roof section which is fire protected polycarbonate be from the flue? Can it be covered after a certain height? Or can I run a 90 bend sideways to avoid the structure all together and then put in an additional 90 degree to face the flue upwards? 

Any help would be greatly appreciated! 

southcoastrgi

Boiler make & model ?

DevilDamo

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/468872/ADJ_LOCKED.pdf

(Pages 49-50)

I’m assuming “F” relates to your situation?