How reliable / easy to fit are the penetrations for putting flues through a tiled roof? I have the choice between going through a brick wall between two windows (700 mm wide, so just meets the 300 mm clearance criterion, if I read the rules correctly) or going straight up through the roof (concrete double romans).
I think the roof would be slightly neater, but is there much risk of developing leaks round the flashing over time?
Access is no problem as I have a tower up there at the moment.
TIA