When replacing their windows, most DIY boat owners use plastic (either acrylic or polycarbonate). Plastic is easy to work with and produces seaworthy results.
Title explains it... got a customer with polycarbonate windows and wants them tinted. Whats the longevity you've experienced with these types of windows.

As we can see from the illustration, Marine Polycarbonate Windows has many fascinating aspects to explore.
Our polycarbonate marine enclosures in Pompano Beach are of the highest quality, providing protection from the sun, waves, and weather.

TUFFAK polycarbonate from Plaskolite is one of the most popular materials for marine enclosure windows.
High Quality Flexible Marine Grade Polycarbonate.Polycarbonate Twinwall | Bronze. Endless applications for architectural design, roofing, glazing, windows and installations.