Hello all,
Advice from professional roofers would be appreciated. I have read as many previous posts as possible but thought I would ask for some really up to date opinions.
I have permission to build a studio/workshop/office as a lean to inside a walled garden. the garden walls are double block, cavity (500 mm thick), 2.5 m high and rendered. The building would utilize three existing walls - the front (lower wall) being added. I cannot raise the height of the existing walls and the roof must not be visible from the road (back of the rear wall).
The building will measure 10.5 m x 5.75 m. Given that I need 2 m headroom at the front of the building, we have to put up with a very low pitch; less than 10 degrees. The intention is to put supporting purlins (225 mm x 75 mm) down the centre (length) atop internal walls or pillars, 100 mm x 50 mm rafters fully boarded outside with wbp ply, 100 mm insulation and foil backed plasterboard beneath. Roofing material is the main issue. Planning wanted tiles but clearly this is not possible with the pitch and they have accepted this. My current thoughts are for EPDM but (1) I have not used it before and (2) it seems too good to be true in some ways.
The property is in SW France, the roof will face due south and be in full sun all day; we regularly get 40C plus and the rain, when we get it, can be very heavy and prolonged. Winters are quite short but we can get very cold periods of down to -15C. 

Within reason
cost is not an issue - I am in my late sixties and do not want to do this again in ten years time! Appearance is not really vital as the roof will only be seen from within the garden but we would like to to be as pleasant as possible.
Sorry for the long post but it seems that replies usually have to ask for details and I am trying to avoid this.
Many thanks in advance,
Stan
Advice from professional roofers would be appreciated. I have read as many previous posts as possible but thought I would ask for some really up to date opinions.
I have permission to build a studio/workshop/office as a lean to inside a walled garden. the garden walls are double block, cavity (500 mm thick), 2.5 m high and rendered. The building would utilize three existing walls - the front (lower wall) being added. I cannot raise the height of the existing walls and the roof must not be visible from the road (back of the rear wall).
The building will measure 10.5 m x 5.75 m. Given that I need 2 m headroom at the front of the building, we have to put up with a very low pitch; less than 10 degrees. The intention is to put supporting purlins (225 mm x 75 mm) down the centre (length) atop internal walls or pillars, 100 mm x 50 mm rafters fully boarded outside with wbp ply, 100 mm insulation and foil backed plasterboard beneath. Roofing material is the main issue. Planning wanted tiles but clearly this is not possible with the pitch and they have accepted this. My current thoughts are for EPDM but (1) I have not used it before and (2) it seems too good to be true in some ways.
The property is in SW France, the roof will face due south and be in full sun all day; we regularly get 40C plus and the rain, when we get it, can be very heavy and prolonged. Winters are quite short but we can get very cold periods of down to -15C. 

Within reason
cost is not an issue - I am in my late sixties and do not want to do this again in ten years time! Appearance is not really vital as the roof will only be seen from within the garden but we would like to to be as pleasant as possible.Sorry for the long post but it seems that replies usually have to ask for details and I am trying to avoid this.
Many thanks in advance,
Stan
