Tarion Warranty Corporation

Tarion is a builders warranty. It's mandatory to pay for it but you will be sorry you ever got involved with them.
Their mission is to give Ontario home buyers consumer protection and confidence that their new homes are properly built. That is so far from the truth. They only act in support of the builder.
You will be much better off to fix any defects on your own or hire a lawyer if it's a major issue and the builder won't help you.