The materials your builder/contractor will need to build your shelter should be available from building material suppliers in your community. These materials have been carefully selected for their strength, durability, and/or ability to be readily combined in ways that enable them to withstand the forces of extreme winds and the impact of windborne missiles. Your builder/contractor should not substitute any other material for those specified in the designs.

One of the most vulnerable parts of your shelter is the door. The materials specified for doors in the shelter designs in this booklet were tested by the Wind Engineering Research Center at Texas Tech University for their ability to carry wind loads and prevent penetration by missiles. The installation of the door is as important as the materials used in its construction. Please confirm with your builder/contractor that the door to your shelter can be installed the way it is shown in the designs included with this booklet.

A complete list of the shelter construction materials, with their expected strengths or properties, is included in the shelter designs provided in this booklet. Your builder/contractor should use it when buying the materials for your shelter.