ladder length?

[not very handy]

I need to get onto a 10' roof, what length ladder would be best/safest considering the pitch of the ladder?

[pushkins]

Rule of thumb (and code/OSHA rule) is 4:1 for every 4' up the ladder should be 1' out from the wall plus also 3' past the edge of support.

So technically for a 10' roof you need to have the ladder 2.5' out from the wall, this would make the total (code) length of the ladder to be around 14'.