Hello,
There is a ladder that you cannot climb after 1.6 patch in Survival.
It is located southeast of the map.
Ladder and loots on the roof can be seen in yellowish color and players would see as interact-able object,
so obviously the ladder has an issue. I used to use this ladder to obtain loots on the roof but now it is inaccessible.
I am attaching both after/before patch videos.
I didn't find the right solution from the internet.
References:
http://forums.ubi.com/showthread.php/1617455-Unclimbable-ladder-in-Survival
Energy Efficiency Video Examples
