Why is the Type 1-A Model 17 listed as 15 feet in the extension position?
This is how OSHA classifies all extension ladders, and is common among all brands of ladders. They take a measurement of all the ladder sections laid end to end and classify the ladder as that height of extension ladder. Therefore a typical 24 foot extension ladder really isn’t 24 measured feet high, but rather the length of the combined ladder sections. When you take into account the necessary overlap of each adjacent ladder section you lose some of the ladder height.
