Metal strap used in the United States needs to adhere to ASTM D3950. The most surprising tolerance is +/-.002″ for thickness. That means that your .029″ steel strapping is likely to run .002″ thicker, or almost .031.” In fact, most manufacturers make only one thickness for 1 1/4″ x .029/.031″. The loose ASTM tolerances for metal strap mean you will likely get the same strap for either thickness you choose. On paper, the 1 1/4″ x .029″ has a 6% cost savings, but our testing indicates that it just isn’t true.
Need more proof? Look at the break strength for 1 1/4″ metal strap in .029″ and .031.” The break strength is the same.