When I was green in the HVAC world in the 80's I got sent out to a property with a 40 foot aluminum extension ladder for a co worker,I get there and he has his cube van backed to the wall and he is on the roof of the cube van with his own ladder."bring that thing over here and help me set it up." Guy set up a 40 footer [37 usable feet] on the slippery wimpy roof of the cube van with like 1 rung over the parapit wall I asked him isn't there a scuttle/hatch? Yeah thats all the way on the other end too far away-I do this all the time.I wasn't goin up there so I hung out below"holding the ladder"-yeah right with the 2 way ready to call base if he came tumbling down [he didn't].Way hairier ones than I have!! Later Steve!!