Solar panels, how high should they be above the roof

Another way to go is w/ a 1/4" x 1" alum flat bar 3" long, pop riveted to the inside of the panel all 4 corners. Then those get drilled and tapped 1/4-20 for the plastic knobs bought at any good hardware.

Thanks.
I'm bolting some angle to the frame of the panel using the factory mounting location (I've heard drilling the frame will void the warranty?) and another piece of angle to the roof with a bolt between the two.

No shortage of rain up here normally, dry as a popcorn fart this summer though, stage 3 water restrictions, no lawn watering at all, can't even wash vehicles (or rv's).

i'm going to re do some of mine
2" on the front edge 3" in back
yes water run off , helps keep from making dirt puddles, when stationary water dries up

we don't get very many really good rains that wash the panels

get some "nutserts" aka Rivnuts and the tool for setting them to the panel
using a permanent nut on the panel for fastening to the bracket
makes it easy to loosen the bolt and clean under the panel
or add tilt bars

I'm not getting any mounting brackets, that's why I'm making some, (plus I don't like the idea of Z brackets).

The 4 little bracket's that you get with a panel are all you need to mount a panel, you don't need them sloped to let water run off them, unless you are gonna tilt them 1" off the roof is sufficient. Just my thought's.