What about weather resistance of polycarbonate?

All polycarbonate sheets destined for building applications are UV-protected. This is achieved by a thin layer of UV-absorbing material that is inextricably bound to the sheet surface. This layer absorbs and neutralises all harmful UV-rays present in sunlight. Such sheets typically have a 10-year warranty on weathering behaviour. Next to that, you can also find sheets without this supplementary protection for industrial applications such as machine glazing. Such sheets do not carry a warranty on weathering behaviour.