Sunlite contains a UV stabiliser that slows down the effects of the sun's punishing treatment on the sheet. However, as with most PVC translucent sheets, this stabiliser will not protect the sheet altogether. PSP therefore suggests that this product should not be used for skylights in your home.
Instead, we recommend the use of Suntuf (Link) Polycarbonate Sheets for this purpose, as SUNTUF is more durable in this situation. The use of Sunlite should also be avoided in the main envelope of a building such as the roof.