Wind Frame Bracing 101: From Basics to the Secrets
How do you protect your steel building against wind, snow, collateral, and seismic forces? In short — wind frame bracing. The main structural elements of any steel building are the main columns, wall girts, and roof purlins. These members make up the “skeleton” of your building by supporting the roof and wall panels, giving structural integrity, and helping to allow for a water tight seal.
Let’s think about the dynamic forces in play that act upon your building. Think of a house of cards, built with sides and a roof, but no interior structural support. Now think of how easy it is for a house of cards to topple over. This is where wind framing comes into play. Without wind framing members, your building would be at the mercy of wind and seismic forces — allowing the building to sway and flex — ultimately causing a catastrophic failure of the structure.
Typical wind framing consists of an “X” pattern of either cable bracing or rod bracing, depending on your geographical location. These braces are placed every 100’ across the length of your building, on average. Alternatively, they are placed every fourth or fifth bay (depending if your bays are spaced at 20’ intervals or 25’ intervals) on the walls and roof evenly.
Your Bracing Options
Cable bracing is the less expensive option, but will require re-tightening every 3 to 5 years. However, almost no one takes this factor into account, which can lead to less overall stability of the structure over time.
Rod bracing, on the other hand, is as you might imagine — more rigid, with zero stretch, and stronger than cable bracing without the need for re-tightening. This makes for a more stable structure over time for only a few hundred dollars more per structure. At Solid Steel Buildings, we rarely implement cable bracing because we believe in giving our clients a maintenance free building that can withstand rigors across multiple environments and building codes.
The final bracing type is called portal bracing. This type of bracing is utilized when an opening — such as a garage door, window, or walk door — must be in a bay where wind bracing is required by engineering standard. Portal bracing is essentially two vertical steel members welded to the vertical columns, with a horizontal header member attached to the vertical members spanning across the top of your framed opening. Portal frames allow for flexibility in placement of framed openings; however, each portal frame costs a few hundred dollars more than regular “X” bracing. Flexibility is the key with your building design, so portal frames are a good choice when control over ingress and egress locations are of absolute importance.
Obviously, the engineering and science behind steel building loading is far more in-depth than we can discuss in this month’s blog. Rest assured that your Solid Steel Building team is proficient in engineering practices to ensure your building is able to withstand the rigors of your geographical location — ensuring a worry-free structure for years and years of service. Contact your Solid Steel Building Representative today and let’s get building together!