That window design looks like it would never seal properly.
Here in Germany any window from the last 30 years or more will not let any air in when its fully closed.
Double hung windows don’t seal quite as well as casement windows, but honestly, unless you’re going to the absolute best energy efficiency possible, like a net-zero house, then it’s really not a big difference. Any halfway decent quality, properly installed window won’t have any noticeable drafts. Plus, as others have mentioned, double hung windows are far cheaper than casement.
That window design looks like it would never seal properly. Here in Germany any window from the last 30 years or more will not let any air in when its fully closed.
Why wouldn’t it seal?
Because its not possible to pull the window into the seal when the window also needs to move up and down.
We actually have the opposite issue. Windows here seal so well that indoor air quality slowly drops if you don’t run the central fan all day.
Double hung windows don’t seal quite as well as casement windows, but honestly, unless you’re going to the absolute best energy efficiency possible, like a net-zero house, then it’s really not a big difference. Any halfway decent quality, properly installed window won’t have any noticeable drafts. Plus, as others have mentioned, double hung windows are far cheaper than casement.