offset parameter in formular

[Anonymous]

Guys, how do I write a formula to use the default offset of a device, inside that family? 

For example, I wanted to say that if a box family is 10' high, I want to subtract from that offset 4 feet.

Can I create an offset parameter..but how does it know that this offset is the actual offset when we place it inside a project..?  Thanks!

[barthbradley]

Make the offset a reporting parameter.

...actually that may not work. If you want to post the family, I'll fix 'er up

[Anonymous]

Here is the family and images to help explain.  I'm surprised you cannot use a system parameter {Offset} to call the actual offset that's seen in the property inside a family/formula.  Thank you!

[barthbradley]

I'm not following your thinking here. This is a level hosted family. It will insert at whatever offset from level you choose. There is no built-in intelligence. You can set a default offset (similar to a default sill height) directly in the family  -- and you can constrain everthing in the family from that offset distance. 

[Anonymous]

I guess my goal was to create hanger that would automatically extend to the bottom of the slab, based on its offset.  The slab number could be changed as an instance, and the offset number I need is the actual offset of the family, when inserted.  Knowing that number, within the family, I wanted to create a formula to control the length of the hanger (allthreads) so that if the ceiling height is 15 feet, the slab is 6", the fixture is placed at 10 feet offset, that the length of the offset would be the ceiling height minus the slab, minus the offset: 4'-6".  If I can somehow control the offset number within the family, then I can use that number to control the length of the allthread - minus the slab thickness.  I will try to create an offset or height parameter within the family and do it that way.  I didn't want to create another parameter, if the default offset is already provided.  This way I don't have to update the height also. Hope that clarifies it a bit.  Thanks.

[Sahay_R]

@barthbradley - this is a duplicate thread - I have already given OP a ceiling hosted family which would not need manual entry of heights at all.

[Anonymous]

Yes, I was surprised why it's showing up in 2 places.