Hello Daniel, the enclosure is highest quality and depending on region we give warranty up to 15 years (aluminium profiles and filling). The filling can be two types of polycarbonate sheets (clear compact or twin-walled, chambered polycarbonate) or security glass. The enclosure can normally be used spring to fall. The greenhouse effect really depends on the amout of sun your terrace gets, type of tiles, color, etc. If you want to be able to visualize the temperature difference, imagine a greenhouse it not only keeps heat in, but also keeps the wind out. Please contact me if you have further questions, I can hook you up with one of our official dealer for your area. kubes@enclosure.guru - George