Tornados vs pole barns

[jmc]

Tornados thru here yesterday, about 30 miles SSW of Indianapolis. Sure looks like the roof in the attached pic was by far, the weak link. Building's walls unscathed, despite being giant sails with little support, once the roof left the building. Several years ago, after hurricanes in the South, postmortems on some of the damaged houses indicated a little extra hardware holding their roofs down might have saved them. Maybe our pole-barns could use some too?

 

[teejk]

Hurricanes are not the same as tornados. Not much hardware is going to save any structure in the path of the latter.

 

[ruffdog]

If a tornado goes over that sealed building and drops the barometric pressure a few PSI, the roof will be coming off. (or so some say....)

 

[RNeumann]

That building doesn’t look like it had a holddown failure. Looks like broken trusses etc.

The Simpson H1 holddowns kept the entire roof from separating from the walls- trusses, sheathing and roofing as one unit.

Anyway thx for posting. It helps put some things in perspective.

 

[kenmac]

Pole barns, (along with many other things) don't hold up very well here when the tornado hits here either

 

[MossRoad]

If a tornado goes over that sealed building and drops the barometric pressure a few PSI, the roof will be coming off. (or so some say....)

That used to be the common perception, however, it's not what happens. Usually, the tornado rips the roof off, then there is little lateral support for the walls, and they collapse with wind load.

I know every time there were tornados when I was a kid, my mom would run around the house like a nut making us open all the windows so the house wouldn't explode. Believe me, it wouldn't do squat to open the windows, and might actually be of more harm, because it would let massive winds into the structure.

 

[buckeyefarmer]

I have the hurricane clips on my trusses. I doubt they will hold in a tornado.

 

[ovrszd]

That pic is unique. I see no reason the roof should have came off. But, maybe the overheads were open?