Red Herring Pipes?

Ever wonder why some pipes are called "tap and die?"

Today in Contracts class we learned about a case where a contractor didn't get paid because he used the wrong brand of pipes while building the house. He went through all the hard work and didn't get paid eventually because he didn't use the particular brand of pipe that he agreed to the owner in the beginning. And to demolish the whole place just to replace the pipes would take a whole lot of money too.

What do you think the result of the case should be? If you're the owner, wouldn't you want to make sure that the pipes you specifically requested was used? And if it wasn't, then its not your responsibility to pay right?

But for the contractor, yes he made a mistake, but he also used his labor, time and other materials to build everything. Just because the brand of pipe was wrong doesn't mean he can't get paid at all.

Hahah..

Ok. I'm totally not answering my initial question at all. I don't know the answer. =P