Dimensioning to grid intersections

[Mike Sealander]

This is a "why" question:
Why can't one dimension to a grid intersection? There seems to be a lot of places where I can snap to a location, like a grid intersection, in order to draw a line. But those same places aren't snap points for dimensioning.

[jeff.95551]

Interesting question, but I'm having a hard time imagining where I would want to do this. The point of grids is to keep dimensioning perpendicular from the grid line. If I'm dimensioning to a point that's 27 degrees off of a grid line, I'm going to dimension the actual distance it is in each direction perpendicular to the grid lines (even if the grid lines aren't orthagonal). That's how they will lay it out in the field (or prepare it for gps layout).

The issue is probably with the dimensions and has nothing to do with the grids - since a dimension is attached to an object (and an intersection point is not an object), Revit won't let you go there. It is very common when I need to dimension 2 things that aren't quite parallel to draw a very short line that is parallel and that is in the right location and dimension to that. I'm sure that would work.

[Mike Sealander]

I do a lot of field layout. So, I pull a lot of diagonals to check square. That's why I want to dimension to intersections of grid lines.
The other reason is I use arcs a lot, and occasionally need to dimension from a grid intersection to a location on a curve.
Suffice it to say I find the need. I think you're perception that dimensions are tied to objects, and not intersections of objects might be part of the issue. However, one can dimension to the intersection of many types of objects, but for some reason if both objects are grids, one cannot.

[Dimitri Harvalias]

Dimensioning to the intersection of objects is in fact dimensioning to the intersection of ref planes for that object.
Try creating a column family that consists of two symbolic lines that end at the intersection of the vertical and horizontal ref planes. You can then place that at your grid intersections and because it's a column it will move with the grids when they move.
The one caveat is that this won't work with angled or arc grids since the columns don't move with the grid intersections. You will still be able to dimension to them but you'll have to keep an eye on those locations if the grids move.