Adjusting beam elevation based on slab thickness

When using the Beam tool to layout the framing on plan, by default the current Level has already been selected by Revit as the Work Plane. Therefore, if user draws the beams, they will be referenced to the Level itself only (Figure 1).

(Figure 1)

Also, user has to manually adjust the beams Properties Start Level Offset and End Level Offset so that the position of beams will match the thickness of Slab. By consequent, if the thickness of Slab changes, the beams will not follow or auto-adjust with the Slab (Figure 2).

(Figure 2)

Currently, Revit Structure doesn't have a direct feature to "attach" beams to slab. However, there is a solution to quickly draw beams that will associate with the Slab instead of the Level which is to use the 3D Snapping option when drawing the beams on plan (Figure 3). This option allows Revit to select automatically the underside face of the Slab geometry as Work Plane and places the beams underneath it. As a result, if the thickness of Slab changes, the beams will follow and auto-adjust with the Slab (Figure 4)

(Figure 3)

(Figure 4)

P.S. I know that some customers use the method of drawing the Ref. Plane by assigning it as the Work Plane, then aligning and locking it to the bottom of Slab. This method would work fine as long as the Slab is horizontally flat, but if user decides to make it sloped then the constraint will break and the beams will no longer follow the Slab.

Comments

[Mr Spot]

I assign beams to the underside of slabs all the time. Simply set the underside of the slab as the work plane first...

Also if you need it to still associate to the slab but be offset completely rather than using the offset start and finish parameters change the z direction justification to other then set the offset you require. That way you are working with one elevation and not two...

HTH.