The roof is made out of zintec steel. It was cheaper and more fun to make the roof myself. I folded sheets of steel into the correct shapes, then cut and punched holes so when the roof was fitted it would blot together with M3 bolts.
The roofing system has panels (tray shaped) coming together to form a T-section, which are bolted together. Then a C-shaped length of steel is pushed over the T and crimped together, securing the panels together. The gable flashing join the same way and the wall flashings are crimped onto the bottom of the roof panels.
The Solar panels are bolted to the T section.
I was very lucky as I am a metal worker and therefore I had all the equipment I needed to make the roofing.