How to lock window head heights in with parameter

[johnw]

is there any way to create a parameter that allows a window to always come in at a certain head height by possibly creating a "head height" distance to the parameters dialog, and then subtracting the window height from this head height number to then set the "sill height" parameter automatically?

That would always keep your window head height the same if you change window sizes...

Is this possible?

Thanks,

John

[FGPerraudin]

Of course it is very possible.

You can either lock by entering a value inside the formula column

Or enter a formula to calculate the sill height according to the top height!

Revit is amazing in that way!

[johnw]

Where would I put this "formula"? Next to the "sill height" parameter? I've tried to do this in the past and it kept saying there was circular reference error or something like that... I could never figure it out.