Stiffer Building Codes

 This morning's tornado hit has killed 70-80-100 we don't have a full count yet.  TV of the worst hit buildings show a lot of damage, some deaths, but the roofs look like they almost stayed on.  When things settle down, they might have the building code people look at the damage and make recommendations for stiffening the building codes for new construction to make the area a little more tornado proof.  More hurriquake nails?  more steel angles holding the roof on?  Something else?  Anything?