Assuming this is regarding Zinsser Allcoat Exterior for brush, roller or airless spray application, the ambient temperature would determine wether solvent or water based should be used.

For cooler temperatures but above 5°C minimum we would recommend the sovlent based, for warmer temperatures during the summer water based would be better suited.

Assuming the upvc is clean, dry, sound and prepared as detailed in the technical data sheet any of the water based or the satin solvent based can be applied directly.

If you wish to use Zinsser AllCoat Exterior Gloss (Solvent Based), the upvc must be primed first with Zinsser Bulls Eye 1-2-3.