these (see pic) awning window winders can indeed be locked. but using the winder, someone can come along (ie. kids, coworkers) and wind it closed. i wish i could find a solution to keep it opened, especially considering the importance of fresh air on a building.

I have just checked my awning window, and correct you can't lock it to a certain point of opening. It can only be locked at closed.

Could you get a metal brace made, with rubber surrounds, to be attached to either the sill or window frame. Attached with brackets so it can be removed if window needs to be closed completely.

Just trying to think outside the norm. You could just use a couple of bits of wood, but a metal brace may look more professional.

thanks for posting. it means alot to me. the metal brace idea sounds good. it does sound somewhat permanent. i still hopeful to find a solution where I can lock it open for a few hours a day. especially in winter when it can be too chilly to keep the window open too long.

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