I have a home made conservatory on the house I\\\'ve just moved into, and it has a downpipe against the house wall going through the conservatory roof. The roofing is polycarbonate sheets, nailed to wooden joists. The flashing is knackered, it looks like kitchen foil type stuff. I want to replace, to make the room watertight, as it currently isn\\\'t. I\\\'ve seen a roll of flashing tape in the ScrewFix catalogue but am beginning to make some enquiries to do it properly - any advice from you learned folks would be most welcome and appreciated?