You don`t caulk cast rainwater pipes they just fit together loose - the big pipe nails hold them firm enough , even for cat burgulars. Either way you`ll have to take the pipe away from the wall to insert a diverter - you can use screws and washers instead of pipe nails when replacingthnaks for your reply. Does the cast iron diverter kit have to be joined by the traditional way though as I have not caulked etc before and not sure how to?
If I did use the normal one, as you say it may look s**t, even if I did "try it", after cutting the 30mm of pipe from the down pipe, would it be possible to slide the diverter on without removing the bottom part of the downpipe from the wall?
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