We had an EPDM flat roof fitted to an extension a year ago. Recently we had a few roof tiles come down off the main roof - they are large concrete Hardrow ones. They didn't come down on the flat roof but my question is, if they had done, which might be possible in future, could they have pierced the membrane, and if so, is the EPDM roof repairable/patchable? I assume you don't have to replace the whole thing - shudders - it cost over £4000! Thanks.