Greetings @Stuntcabbage ,
Thank you for reporting this issue to us, but could you please use the given Bug Report Template?
This template has most of the information we need to start investigating and will make the process a lot quicker for everyone 
You can find it here: NEW Bug Report Template
We can see that you mentioned you don’t want to put anything on tiles. In this case we highly suggest you to use foundation pieces since this will assist in your building and decay timers.
Thanks in advance!