The aluminum sun screen is installed at the balcony railing location. You could still use the balcony. There is also another one that I happen to come across where the blades could be adjusted. Not sure if it could be rolled up.

BTW, I think there are also the timber kind that works quite the same like the aluminum sun screen. Try google...

Install turbine ventilators, aluminum insulation sheets, install rockwool in the ceiling, paint your roof with Nippon Solaroof paint 

hahaha. Cannot install on the wall la... That's not how the turbine ventilator works 

To give you an idea, you could look them up in the net or read  HERE

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