Manual built (not automatic), Ladders are built into slab buildings from ground, not from the first point of contact

[Yosmo78]

Summary:
Ladders are built into slab buildings from ground, not from the first point of contact
Steps to reproduce:

1. Build a slab wall with one block sticking out at the bottom
2. build ladder against wall on the block
   3)bug is produced

Expected Results:
ladder being on top of block
Actual Results:
ladder goes through the block
Notes:
Link for template Dropbox - wooden wall.json - Simplify your life
world file: Dropbox - 1455384802798.zip - Simplify your life
Attachments:

Version Number and Mods in use:
Dev 523
System Information:

[BrunoSupremo]

I have seen this happen with automatic ladders too, not on this version though.