Is a UV filtering glass best for pictures hung in a conservatory?
The only glazing material to use in a conservatory or similar environment is a thick piece of plywood or hardboard. In other words, advise clients never to hang valued artwork in such conditions. Regular high levels of visible light (sunlight in particular) will still cause permanent damage to artwork – as will the wide range of temperature/humidity conditions also typically found there. If artwork is worth conservation framing, it should be hung out of the way of direct sunlight or even clear blue skylight and also away from radiators, heaters and damp conditions.