Disable/enable ladder interaction?

[Damascus]

It seems that players can still climb a ladder area that's been set "inactive," so is there any other way to keep a player from interacting with a ladder area until something triggers it?

I have a ladder area that's set up behind a breakable cell wall, and want the player to destroy the wall before climbing down the ladder, but it seems like all they have to do is look through the hole and click the ladder to proceed. I've tried putting a large block_box in the way, but I can still reach through it to click the ladder.