You have no legal obligation to insure your residence. However, if your residence is financed by a financial institution, the institution will require that you insure it to protect the financed property. Even a property that is mortgage-free should be insured. After all, it costs only a few hundred dollars a year to protect your most precious asset—which often has cost you hundreds of thousands of dollars.
Your home represents an important investment for you. Whether you are an owner or a co-owner, you should take the measures required to properly protect this investment.