Gaps can appear around any type of window frame, on a house of any age. They may be caused by natural settling of the house cracking existing mortar or just by bad workmanship when the window was fitted.
Not many houses still have old steel-framed windows nowadays, but some do and unless you plan to replace them with wooden or UPVC frames, you should know how to maintain them properly.
Although this might seem like a simple job, painting window frames should always be completed in a certain way.
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