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No earlier than 1832 and no later than about 1855, I'd say.
The house on the end of that terrace (11) has been unmolested and carries its original four pane sash windows. The reason it has 4 panes is that that was the largest size of glass that could be cheaply made at that time. Note that round the back they have much smaller panes because the expensive stuff was reserved for the front. Sheet glass was invented in 1832 and was widely used by 1837. as the century rumbled on the sizes that could be produced got bigger, and the single pane sash became commonplace. You'll see that many of the houses in that terrace have single pane sashes but they will be conversions or replacements, "keeping up with the Joneses", because the decreased rigidity caused by losing the central fenestration necessitated the use of 'horns' to strengthen the sashes, as at no.23. It would have been unusual for a sash window frame to be produced without horns after the middle of the century, but 11 and 13 do not have them.
They don't need to know exactly, just roughly. Show us a picture.