Face-based family: some components floating despite the same elevation

[adamskaEXHPY]

Hi guys,

I am loosing my mind over a face-based family issue. I have created a tile as a generic family and constrained its base to the surface in the family creator. Some work just fine but some are floating at the ground level despite having elevation set to -10. 

Any idea how to fix it?

Thanks!

[ennujozlagam]

have you check your =base constraint in the properties or post the file so we can check. thanks

[adamskaEXHPY]

Hey, it's floor based and I have constrained it "manually" by aligning and locking the faces - is there any other way?

I have attached the file.