There are several different options for glazing balconies.
1) You want to protect the balcony from street dirt, rain and wind.
In this case, the simplest glazing from an inexpensive profile and a single -chamber double -glazed window is suitable. For even greater savings, you can use cold glazing. Plus such glazing — low cost, sliding windows open in the direction of the balcony, excellent protection of the balcony from bad weather. Despite the fact that such glazing is called cold, you should not think that in winter it will be as cold there as on the street. The temperature with such glazing never drops below zero.