Being that it is early spring, it may be a good time to think about taking steps to protect your family in the event of a tornado. The 4th Edition of FEMA P-320, introduced below, contains a “treasure” of design information for constructing a residential safe room, either in the home or as a detached structure. The FEMA document and structural drawings are free to download. Visit https://www.fema.gov/fema-p-320-taking-shelter-storm-building-safe-room-your-home-or-small-business.
I wonder out loud if MPC wood trusses could be used to design and construct a “prefabricated truss-frame” storage shed/safe room building that would safely resist the FEMA recommended wind speeds? With the requisite hold-down-hardware embedded into the truss-frame, the building could be delivered to the site ready for the concrete foundation work needed to secure the shed/safe room.
Some readers might remember the efforts of the US Forest Products Laboratory in the late 1970s to develop and test a “truss frame house.” One obstacle to implementing the idea stemmed from the lack of architectural flexibility as the system utilized identical truss frames for the roof, walls, and floor framing. Visit https://www.fpl.fs.fed.us/documnts/pdf1982/ander82a.pdf for more on the truss frame house. However, for the case of a small storage shed, a simple rectangular shape may not be viewed as an obstacle, but as the norm for a storage shed.
From the FEMA P-320 homepage
FEMA P-320 – Taking Shelter from the Storm: Building a Safe Room for Your Home or Small Business
Having a safe room in your home or small business can help provide near-absolute protection for you and your family or employees from injury or death caused by the dangerous forces of extreme winds. Near-absolute protection means that, based on our current knowledge of tornadoes and hurricanes, the occupants of a safe room built according to the guidance in this publication will have a high probability of being protected from injury or death. Our knowledge of tornadoes and hurricanes is based on numerous meteorological records as well as extensive investigations of damage to structures from extreme winds. Having a safe room can also relieve some of the anxiety created by the threat of an oncoming tornado or hurricane.
Should you consider building a safe room in your home or small business to provide protection for you, your family, or employees during a tornado or hurricane? This publication will help you answer this and other questions so you can decide how best to provide that protection. It includes the results of research that has been underway for more than 30 years by Texas Tech University's National Wind Institute and other wind engineering research facilities on the effects of extreme winds on buildings. Download the entire FEMA P-320 document.