While there are no true tornado or hurricane "proof" homes, many things can be done to create a tornado or hurricane resistant home. Tests have shown that concrete is one of the best materials available when building tornado and hurricane resistant homes in areas with severe weather and high wind situations such as tornadoes and hurricanes.
The above photos were taken in Florida after a tornado. As you can tell the concrete homes are still standing with only minor damage. The image to the right is a traditional wood frame home in the same subdivision.
The roof design on the concrete homes were constructed using lumber with hurricane straps and survived with little damage. Another option would be to pour a solid concrete roof. With the Precise Ledger System it is easy to create a flat or pitched concrete roof adding additional safety and duribility.
Standard windows can easily shatter in a tornado or hurricane causing glass shards to become deadly projectiles. Tempered glass will provide additional protection by staying in large pieces even if broken. It's the glass used in vehicle windshields for this specific reason.
Metal or wood shutters (hurricane shutters) offer additional protection for your windows and your home. You will, however, have to shut them in a timely manner should a storm approach.