flat roof drain

We are having a rear extension built professionally, it is a two storey rear extension but as we are semi-detached it is single storey on the side that connect to our neighbours property. This area has gone in as a flat roof, with appropriate slope for water drainage. The slope (designed by an...

Hi all Currently renovating our bedroom. We have a bay window which has leaked on and off. We thought we fixed the leak by painting some of that liquid roof stuff on and repointing the stone. But there's been heavy rain and I think the internal drain is failing now. I noticed the damp again...