i have a biasi activa 35c boiler and need a flue. my question is will I need a flue kit to match my boiler model or could I use a standard biasi flue kit for example like the one here http://www.diy.com/rooms/biasi-condensing-standard-flue-kit/34759_BQ.prd
Thee is no such thing as a standard flue, each boiler has its own specific flue although some companies the likes of Worcester, Vaillant only make one flue for their entire range. You will need to check either your manufacturers instructions or with Biasi for the specific flue kit for that particular model. I'm sure that your gas safe installer will be more than happy to chase it up for you, be aware that flues are classed as gas carrying parts and should only be installed by a qualified person.