[lrae]

Sash windows are just not as common. Seems like they are in the UK somewhat, though numbers I found vary, but overall in Europe they're pretty uncommon.

And yes, there are options for tubes/ducts for the more common window types. Like tilt-and-turn windows, horizontally sliding or all the other kinds of inward or outward opening windows - but most of them are the ducted portable units the original comment was speaking of, which aren't great. There are also some better portable split units, but those are pricier and the install is not as easy. (They're great though.)

[mc32]

one issue with tilt and turn is getting window screens for them. It's possible but mostly they get installed on the inside if you have the proper wall spacing that allows window to function without interfering with the screen. mini splits are great but it's much more money than a simple window unit or portable unit.