In one bathroom we did a little while ago, we put a horizontal sliding timber window with opaque glass and a mossie screen. Located above head height and painted. Right near the main wet area in the bathroom. Enables the bathroom to dry out each day properly even in winter. So very functional and also appropriate amenity for both us and neighbours ie not see out and not see in when open due to location. Window is 1500w x 500h. Bathroom size is 3600 x 2200 with the window placed on a east facing 2200 wall. More than enough natural light from sunrise to sunset, but that could be partly due to reflection from floor to ceiling 600 x 300 white wall tiles - which makes it much lighter.
Nothing like natural ventilation. However - although it does not need it - we also supplemented with an IXL tastic. Obviously the ventilation flow needs to be considered, and correct placement is required for optimum effect ie. not next to the window and the exhaust away from the window to prevent recirc. Some manufacturers give proper calculations and placement detailing regarding this - "google is your friend".
Would avoid louvres from my experience. When we had a house in inner Sydney had some louvres in an extension. Scared off an "intruder" pulling the louvres out of the frame (....problem is if I "caught" the dude, then I have to appropriately "detain" the thief.........not so easy without excessive force......especially if it is unknown if there is a concealed weapon on the thief - which is becoming more highly likely in Sydney). They also accumulated lots of grime and in a bathroom environment with condensation and dust - I would find it most annoying.... Other options could also be something like an opening roof window or skylight (something like velux or other).
Our other bathroom has a casement hinged at top. In comparison - not nearly as effective. The bottom location of window commences at waist height and as such can not be opened a great deal without impinging privacy. Even if it was located at a higher level, the sliding window is far more effective - desired outcome is natural light and ventilation from a window.
One thing I have found doing 3 bathrooms - the prior planning with the relatively small space is critical to not only good aesthetic qualities, but more importantly correct functionality. It is in our house a high use area. No point doing something to find it looks good but crap to use, as with a bathroom it is a serious amount of work to undo and redo something.......like one bathroom I had to strip out because of a failed waterproofing membrane from the previous owner....but that is a story for another time....
Confused now? I am.....![]()