I live in the second floor (one over ground level) in a condo building in Germany. It is rented, so I cannot do major modifications. Minor modifications must be arranged with the owner. The living room has a huge window to the south-east. Now in the summer there is a lot of sunshine through that window, the living room gets quite warm and sticky this way.
This summer some plant that has grown wildly in front of the building has made its way in front of my window:
I quite liked it, it looks like I am living in a tree house. Also this plant absorbed the sunlight and made the living room way more enjoyable over the day.
Sadly the facility management had to take it down as this tree-like plant scraped against the facade. Soon they want to paint the facade as well, the tree would be in their way.
Now we have a clear view on the other buildings and a lot of sun in the living room again:
Only the first floor (ground level) flats have outside roller shutters, the higher ones do not have them. We only have curtains but that absorb the sunlight within the room and do not cause much improvement. Also the tree was nice to look at, closed curtains look somewhat sad.
I have thought about sticking some sort of tint foil onto the lower part of the window or covering it completely. Also there is mirror foil available on the internet which will reflect some of the sunlight directly. However, I fear that on rainy days, the living room will be quite dark, then.
What could I do to reduce the amount of heat in the living room on sunny days without obstructing the view to the outside permanently?