Joist Top Elevation Tag

[lily567699]

I have run into a problem with tagging joist elevations using the beam annotation tool. It appears that the "top elevation" tag does not work for joists.

I have a sloped roof system with wide flange beams and LH joists. I have created beams on the column lines, joists between. The beams are offset down to create the slope, and then the beams supporting joists are dropped an additional 5" for the joist seat using the "z-direction offset" tool. This allows connection betweent the joist and the girder to be maintained in the analytical model while the geometry is right for the joist seat. I then went through and tagged all the beams using the beam annotation tool. I set the beam elevation to display "top elevation", to not show when the elevation is zero, and to show elevation tags at each end of sloped beams. The beam type tag appears everywhere, but the elevations only appear on the wide flange beams.

When I switch the elevation display to "actual (selected) elevation" the joist elevations appear. The problem with this is that the beam elevations appear at the level offset, rather than the top of geometry. So the beams that are dropped the additional 5" for the joist seat are tagged at whatever the elevation offset, 5" above where they should be. Currently I'm tagging my project in two steps, selecting all the beams and tagging elevations with the actual elevation tool, then selecting all the beams and tagging with the top elevation tool.

I would like to know why revit is doing this. I'm currently working in 2013, and the last project I did with sloped joists did not have this problem. It seems like the top elevation tool does not work at all for joists in coarse view. In fine view I can select the top of the chord, but when I cycle to fine view the elevation disapears. This seems like an error in the way the joist family acts, but I'm not sure how to fix it. Has anyone else run into this problem? Any thoughts would be appreciated. It would be good to know if this is a problem for others or if something has been corrupted in our file.

Thanks.

[kmarsh]

Hi Lily,
Change the "display elevation" from "Actual(selected)elevation" to "Top" as shown here:
95085

The next part is really odd to me. I worked on this beam annotations project and don't remember putting in any exceptions. However, it appears that joists and anything other than steel beams will not get end elevations. Concrete does not seem to work, joists do not seem to work, precast beams do not seem to get tags. I'm checking on this but it appears that only steel members will get end elevations with the beam annotations tool. (you can, as you have seen, put them on manually).

I might actually suggest not tagging the elevation of the joists at all. They are fixed by the beam on which they sit. You can simply omit them and let the detail show that they sit on the beam (for which you have provided end elevations). I have done many joist on steel beam projects and never put an elevation on the end of a joist which sits on a beam and have never had a fabricator, or erector ask a question about it. So, unless the code of standard practice has changed on this issue, I would recommend only elevating the supporting beams.

Hope that helps,
-Ken

[lily567699]

If you switch the display elevation to actual (selected) elevation in the annotation type box you have screen captured, you will get the tag for the end elevation on the joist. I don't know if it will work for other non-steel beams, but it seems likely that it would. The problem is that the tag reports the end level offset, rather than the top of geometry, which means that any beam that has been offset using the z-direction offset tool shows the wrong elevation. However, for a concrete project or the like that might not matter.

It seems like there's something weird with the top definition for non-steel beams - you can tag individually the top elevation for a medium or fine view joist, and the tag selects the chord, but when you switch to a coarse view the tag stops displaying an elevation (the leader still shows up). So there must be something different in the way the top elevation is defined in the different beam families. I wonder what would happen if you took a steel beam family and edited it to be a concrete rectangle...

[kmarsh]

The "top" setting will have the tag show the top of the geometry so regardless of whether you used z-direction offset or not, it will show the correct elevation. If you use "actual (selected) elevation" it will tag the top of the location line.

The reason the standalone tool works in medium and fine is that, in coarse mode, there is no "there" there. In the view, there must be some geometry for the tag to "find" and tag. in coarse, only the location line is available.

are you working in 2014?

[lily567699]

It shows up in both 2013 and 2014. The project was in 2013, but we created a similar situation in 2014 to see if we could duplicate the problem.

So I guess the real question, is *why* is there no there there for joists (and other non-steel) beams? Is there a way to add a top definition to the joist family? In the project we have some joist girders that do need to be tagged to show the slope, so it would be good if we could tag the top elevation of the chord, showing it dropped for the slope. I guess we'll have to stick with text for now.

[kmarsh]

you can definitely show it in medium and tag manually. It's the situation where the geometry isn't "visible" that the tag cannot find the place to tag it. I've sent a note off to one of the QA guys but haven't heard back yet about the functionality discrepancy. My guess about other non-steel beams is that they are filtered out of the list to be tagged as it was intended to apply to steel only. I'm a bit baffled as to why joists aren't tagging at all. (could be a number of internal reasons but really not sure)