What did i break :(

[dutchuss2016]

Summary:
no clue
Steps to reproduce:

1. create a building (do not start building it just design it
2. move the safety flag into its area
   3)profit (i think)

Expected Results:
No error
Actual Results:

Notes:

Attachments:

Version Number and Mods in use:
alpha 14 no mods
System Information: