I posted a question earlier about installing some underfloor heating, down lights and an extractor fan in a mates bathroom. Again, I know what I am doing but am not a qualified spark and therefore part P regs are a problem. However, I have kept some old colored wiring i.e red & black. If i were to go ahead and do the job without having it certified by a competant spark or notifying the building control people, is there any way that it could come back on me. In other words, how else could the authorities determine that the job had been carried out post part P regs. Hope this make sense.