In my last house, (in U.K.), I took out a stramit block wall from a bedroom, and replaced it with thermalite blocks. Since the bedroom was dark-ish, I built a narrow double-glazed strip (something like 18" x 6') into the top of the wall. It could have been frosted glass - but even my bathroom windows were clear. That was into a corridor where there was another window opposite. Yes, very tall people could look in, or use steps, a ladder - but who'd bother? More important, extra light filled the room. And natural light was free!