How Can A Steel Metal Building Help During Natural Disasters?

How can a steel metal building help during natural disasters? Steel metal buildings don't have screws, so when hurricane winds are strong, they don't loosen up panels. The difference between our panels and...

The difference between our panels and the panels of other steel manufacturers is they are using a cladding to the outside, which is fastened by screws. So if you look at the structure, and you start to push it, if you were a hurricane wind pushing against that structure, all the force that you are putting against that structure is going to be transmitted to the frame by some little tiny screws which aren't even a square inch in diameter. Tremendous force is being put on the fasteners during an event, a hurricane, or earthquake, or flood event. First, we apply the reinforcing mesh, which is a carbon steel. Carbon steel is extra strong steel. We apply the mesh and once we plaster the cement, the entire face of all the studs and the plates engage the cement skin, because cement sticks to steel. That's why we reinforce concrete with steel. They bond together and it's this bond that allows the structure to act as a unit. I mentioned the word monocoque, which means single, single structure, or single shell. It acts as a unit rather than trying to transfer all the loads to tiny little fasteners. We use the fasteners to put it up, but once we plaster the cement on the outside, the forces are relieved directly to the steel structure. So there is a tremendous difference in the structural ability. If you took each stud an inch and a half wide, every one foot, or four, or however you space them, that's a lot more area over the wall and roof and floor.

Let's say a 70 mile an hour wind or 170 mile an hour wind hits the side of the building. It is going to create a force against the side of the building, and it's going to try to push the frame over. If it's going to push the frame over the frame, the frame has to slide against the skin. You can picture that. Two things moving, one has to slide against the other if they start to tilt. And the only thing holding the skin on is "steel building", the screws. The thing holding our skin onto the building is actually glued to the entire frame. That's the difference. So we are not relying on the fasteners in the final hour to hold the building together. And the problem with fasteners is, you have seen this in Florida, the first hurricane that comes along, no problem. But guess what? Each time the wind forces that frame, a little bit moves. It actually loosens all the fasteners. Because the steel screw goes into a steel member, it makes its own thread on the way in. But steel is not like wood. Steel doesn't close back around. Steel is deformed and that's it. So if that screw starts to wiggle, it's now wiggling inside its thread.

The grooves around the screw have made a place for themselves in the steel, which is very thin. If that starts to wiggle or be forced once, it actually forms a little more space around itself, because steel cannot break. You can only bend it. So the steel bends a little tiny bit each time the hurricane hits the building. Maybe the fourth or fifth storm, it starts to get some motion, and by the tenth storm this building is wiggling enough that the roof tiles are coming off or the shingles are coming off or you're getting cracks in the surface between your panels. If you look through the literature of construction today, there is a lot of talk about water penetrating the surface of buildings. Well, everyone is blaming the surface or the shingle guy or the tile guy. Now, those have all been tested in wind tunnels. They're not the problem. The substrate or the frame itself is moving. And when the frame itself moves, all the fasteners are going to be stressed. And if they start to come loose, it's not going to be the first storm or the second storm but after a while this building is... is going to start to deform substantially. And when I say substantially in structure, a quarter of an inch or half an inch deformation is a substantial deformation. It is enough to rip out a bunch of screws if you can picture that. If a screw hold is a quarter of an inch off where the screw was, then you have a major problem.

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