KA-CT

It's absolutely imperative when installing a green or blue roof system, to properly consider the waterproofing layer. Typically, a seamless system is recommended, as these are less prone to failures. Single ply (epdm) unless installed in a single piece, can be prone to welding defects on the laps, as well as root penetration. A liquid applied system works well, something like the Proteus system, which is specifically designed to sit beneath a living roof build up. My best advice would be to approach your chosen system manufacturer for design support in the early stages. They'll make all of the necessary recommendations in terms of specification for the system, they will also provide a list of locally trained and approved installers - both crucial aspects when it comes to obtaining a meaningful, single point warranty for the system. If you're planning to undertake the work yourself, then the 'tray systems' make it perfectly viable for you to do so. As above with the waterproofing layer though, be sure to properly consider the draining, and how the water will be managed from roof down to ground level. I love living roofs, I think they're such a fantastic investment. Absolute disaster when you need to uplift one to find a defect the size of a pin prick in some epdm though! Kevin

An architect or planning consultant is what you need. From a roofing point of view.. If flat, have you considered something sustainable like a green or blue roof covering - Solar perhaps. These can be great living spaces too, in the summer of course! I would generally always opt for a pitched roof where possible, they're less problematic and more aesthetically pleasing (in my opinion). You could consider a lightweight flat to pitched conversion - there are some terrific systems available these days.

I'm sorry to say, but this is classic. And, not at all your fault. Horrible situation 😔 The job of the Architect is not simply to design but also to project manage and administer a contract for delivering the project. You could also have obtained this service from a freelance QS or PM, who would have carried the process forward for you, from where the Architect left off. With technical roofing applications, it's imperative to obtain a spec from the manufacturer and not the contractor - If you ask 3 contractors, you'll get 3 opinions and not necessarily something that meets the manufacturers guarantee requirements. You needed an approved contractor and preferably a single point guarantee with the manufacturer. I know these are available with this type of system. A contract, with the roofing contractor, which detailed all of the nitty gritty in terms of spec, delivery, programme, guarantee, costs, variations, liabilities and payments - Did you have one? This sounds laborious and a bit corporate, but unfortunately this is the reality in today's construction industry. This is also where a QS, PM or Architect could've added some value. If you need someone to do a quick review of the paperwork, to see if you have any claim against the original contractor, before you compromise that opportunity by instructing another - then I'd be happy to take a look. Kevin Connect@constructivetalent.co.uk

I would suggest it's as a result of the party wall and gable both sitting slightly higher than the rafters. Gives the illusion that the tiles are running downhill into the dormer. They're probably not.

I'm a UK based quantity surveyor and project manager with an interest in traditional restoration and sustainable new build. I'm here to follow interesting projects, provide input where I can and generally keep up to date with build trends and new ideas.