Building codes can guarantee that new construction has decent insulation and double paned windows etc. but getting existing structures insulated is hard (esp.

Building codes can guarantee that new construction has decent insulation and double paned windows etc. but getting existing structures insulated is hard (esp. for people who are renting - you can add your own window AC, but you can't replace the windows and insulate the place...) One thing that could help is adding exterior sun shades, keeping the sun from shining in windows would ease the load on the AC (and you can possibly put those up even if you're a renter).