Boarding up Bathroom window from the inside

Hi Yes you can make your bathroom window smaller. In able to have privacy As well as fixing your shower handle at the standard high. Best practice is the remove the existing window, buy another smaller window off the shelf, from one of thr leading diy store and brick up the wall at the position where you want the window to be. If you haven't got an extractor fan allready fitted in your bathroom, you then must fit a bathroom extractor fan So you have a good Vantilation in your bathroom. This will help to keep your bathroom free from mould. Just normal practice, I assume that this is a double brick wall, if so brick up, plasteringredients and tiling from the inside. Matching brick or rendering from the outside of the wall.if it is a stud wall Then you can follow the same way built the stud wall around new small window. Use water proof tile backing from inside then tile. And match the wall from the outside. Some times It is hard to give an advise without seeing the actual job. However I hope I have been helpfull Thanks

I'm afraid the plyboard won't work and went won't help. If your are keen on doing that and tiling it I would recommend using hardibacker board. That is full cement board and it won't mold or absorb moisture.

No problem putting a sturdy frame in place, cls studwork good, but rather than ply I would use a 12mm cement board ( Hardy backer board). As for a vent, if the window still opens that would probably be fine, but if you would like a means to get rid of excess steam a ceiling fan into the attic then vented to outside would be ideal, an in line fan would be recommended

You need good ventilation in a bathroom especially with a shower. Dont use plywood for tiling on , use a cement board like hardiebacker