Trickle ventilation for timber windows

[justabigdisco]

I have recently moved into an old stone house with timber windows. I suspect the humidity in the rooms is quite high - my cushions feel damp in the living room. In my last house my uPVC windows bad a mechanism whereby you could open them a tiny crack all the time to allow air circulation but these ones are either open or closed. I’m concerned about leaving the living room window open as it faces the street. Is there anything I can get to allow the window to open a tiny crack?

Are they sash or casement? If sash you could get something like this that's more for safety but would let you open the window a bit while still being secure enough to leave open while you're in another part of the room.

https://www.screwfix.com/p/brighton-sash-fastener-backplate-polished-brass-58-x-22mm/12811?tc=PB6&dskid=92700058173288989&dssrl=1244072&gclid=CjwKCAjwpMOIBhBAEiwAy5M6YJo-0a8WVksHFB0nKNxli91Px95GwFsgM8ZcJMY-z4OShE2MJDnnKxoCMwMQAvDBwE&gclsrc=aw.ds

Not sash. The fitting is like this (please ignore filth, we are having work done!)

You used to be able to buy a lock that you changed for the bit on the bottom which had a lock with key so that you could lock the window open in the position it’s in now. I’ll see if I can find a link.

Otherwise window restrictors could be what you’re looking for.

You maybe able to add a trickle vent to lower window.
Just search for 'trickle vents' and look at the images.