Hello - I have 2 longish hairline cracks on the lead roof of my bay window. Does the lead need replacing or is there a sealant I can apply to keep it water proof?
There is nothing you can do to repair a lead sheet, that will last as long as a properly laid new lead sheet. You can take it off and solder it and that will last for a long time. Any glues, fillers, mastic won't last and are not worth trying.
