Hi hope someone can help.
I am after a small (box bedroom) secondary glazed window.
the room has a double glazed window but now requires a secondary glazed window for noise pollutions reasons.

Would also like the secondary glazed window to slide open giving access to the main window to occasionally air the room.

It's proving rather tricky to find anyone that does it bar one company i tried and they wanted £750 which i thinks silly.

Does anyone know of a company that does this please?

Inherited it in my present house as all the old windows were leaded and falling apart. Dont know who did it though. Have you considered an opening or sliding UPVC or aluminium window/"door" inside if the window board is wide enough.Would have thought a box room upvc window would be no more than £350
Ebay has new secondary glazing options

you meen like a second double glazed window after the first one?
i did kind of think of that but thought i'd be laughed at lol.