Earlier quoted context omitted.
Yeah, here in WA at least, there are signs up in the plumbing section of Bunnings saying “Stop! DIY plumbing is illegal! Only buy this stuff if you’re getting a professional to fit it!” The reasoning is often “people might contaminate the water supply for a whole street!” Which just points to poor provision of one way valves at the property line. But yeah, illegal. I agree there are limits with what you want to do on…
Well there you go. Probably thanks to a plumbing lobby. Lucky we moved out of WA. A lot of laws can be interpreted as reccomendations :)
Total rort.