A salesman asked me the same question when I told him that I wanted a ladder added on to my truck conversion. I told him that you have to get on the roof to check it out once in a while, have to caulk around vents, clean the roof, reapairs to a tear in a rubber roof,etc. The salesman told me that their roofs do not ever leak, right. Needless to say I had a ladder installed, they had to take off the endcap to reinforce the area to support the ladder.
