Anyone out there clued up as to how the revisions to Part B of the Building Regs are going to effect people who convert their loft spaces?

I've heard from an Architect that they are talking about the need for a sprinkler system for all 3 storey buildings INCLUDING when people convert their lofts. Have googled it and come back with all sorts of arguments to and for, but really want bullet points as to the way it is going. Can anyone enlighten me?

When are these revisions coming in to effect?