Rain passes through ladders just fine, but it doesn't render in the actual 1m^3 occupied by the ladder. In a 1x1 ladder shaft, rain reaches the bottom, but no rain renders in the shaft.
Comments 5
@Joël That Is Not True, Rain Is Not A Solid Block, It Is A Form Particles, Which Are Mainly Used As Special Effects And Can Be Rendered Anywhere, Confirmed, The Game Checks If There Is A Block Below The Rain, But It Does Not Check The Blocks Boundaries And Solidity, Meaning That Any Block Would Block Rain Unless It's Hard-Coded To Go Through A Certain Block.
Ok, good to know, sorry for the mistake. I saw rain can go through transparent blocks like flowers torches and ladders.
What I know is rain/snow don't render in the block the player is in.
Rain doesn't drop where you are standing (so if you look up, it never rains in your face). Rain does fall through ladder-blocks though.
Relates to MC-2484
This is normal, rain is a block, ladder is a block, both can not occupy the same space, just like water and ladders. I don't expect this to be fixed easily or at all.