You may have recently purchased or are considering installation of a MAGNUM® Moment Frame for support of your home in a hurricane prone region. You may be wondering what is so great about this system and how will it protect my home in the next hurricane. This control document provides some basic information for the homeowner to help increase awareness about the engineering behind the Magnum® Moment Frame.

Description and History
Steel moment frames have been in use for more than one hundred years, practically since structural steel started being used in building construction. The invention of the steel moment frame brought about the advent of the modern skyscraper because this technology allowed buildings to be constructed over 8 stories tall. By inventing a pre-engineered, interchangeable system that is easy to erect, Magnum Piering, Inc. has made this advanced technology affordable to the homeowner.

Code Performance
Every MAGNUM® Moment Frame is designed in accordance with FEMA P55, ASCE24, New York State Building Code, New York City Building Code, Florida Building Code, New Jersey Edition of the International Building Code, 2009 IBC, and 2010 ASCE7 codes for hurricane wind loading. These are the same codes used to design the modern skyscraper.

Performance in Hurricane Winds
The maximum story drift (lateral sway motion) allowed under building codes is 1% of the frame height during the worst load conditions. This means a 9 ft (108") tall moment frame has been designed for maximum story drift of 108" x 1% = 1". The worst load conditions prescribed by code for your home is a hurricane event which may produce 130 to 150 mph, 3 second gusts in open coastal exposure. For a typical 60-foot wide, 2 story home (5 moment frame bents) this equates to a lateral force of over 40,000 lbs on the side of your home. This force is about the thrust of a 747 jet engine or the pulling power of a CAT336E, 40 ton excavator. The top of your MAGNUM® Moment Frame will only move a maximum of 1" under these severe lateral loading conditions. This movement is completely elastic and is well below the yielding strength of your frame so it will return to neutral/plumb conditions after the hurricane gale force wind dissipates.