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Tom Weir
2005-02-10, 08:47 PM
I am using the spot elevation function to tag structural footing elevations. Trouble is it will only tag the "top" of footing elevation. What we really need in many or most cases is to identify the "bottom" of footing elevation.

The function does not seem configurable in any way. Does anyone know if there might be a way to adjust the function or make a new family for the bottom of footing elevation?

If not this should definately be a wishlist item for us structural users.

Thanks and have a great day...

Tom Weir
Los Angeles

cosmickingpin
2005-02-10, 10:53 PM
You could create a reflected ceiling plan and adjust your view range so that you are cutting below the footing looking upward at it, tag your bottom of footing elevations, turn off model objects, or leave them on if you do it right, turn off site or topo so you don;t get fill, overlay it on your current foundation plan, and Boom Boom, you have both top and bottom of footing on the same sheet.
I think it would work, I didn't try it myself, but if you give it a try and it works let me know.
Cosmic

Mr Spot
2005-02-10, 10:58 PM
That wouldn't work, the spot elevation tool is not available in a RCP.

Scott D Davis
2005-02-10, 11:00 PM
Top and bottom of footing called out in section instead? You could spot elevation tag them both there.

Mr Spot
2005-02-10, 11:01 PM
One way would be to draw a line on the edge in plan place the spot elevation on this, then change the elevation to where the bottom of the footing would be... You could also set the work plane to the bottom of the footing so the line would adjust height with the footing... Then when placing you spot elevation tab until it selects the line...

HTH.

cosmickingpin
2005-02-10, 11:11 PM
Yes they do. I went to my RCP clicked on spot elevation placed it on a sheet and there it was! I use them all the time. Are you running an old build? Remember I did say to cut below the footing, and look up at it, then you are spot elevationing(if you will) the bottom surface of the footing...

P.S.I just did it on the project I am working on and it worked just fine

Tom Weir
2005-02-10, 11:16 PM
We have to show the elevations on the foundation plan so spotting the elevation on a section would not help.

The Spot Dimension is a great tool, but it should be a little more flexible. Sometimes our engineers want all the bottoms of footings at the same elevation because of building pad considerations. Sometimes they want tops of footings in order to better know where bottoms of steel columns are. I bet the architects here on the forum could also provide examples of both as well.

So we need a tool that can read either the top or bottom of an element. Then we need to be able to add a TOF or BOF prefix.

Thanks....

Tom Weir
Los Angeles

LRaiz
2005-02-11, 12:14 AM
I suspect this may not be a problem of spot elevations but rather a discrepancy with understanding of the structural view nature. In general Revit follows the philosophy of selecting only things that are visible. Thus while placing a spot elevation in plan view you are selecting the top of footing (bottom is invisible and not pickable). Revit thinks that since spot elevation is pointing to an edge and then it should be measuring coordinates of this edge. What is really the underlying conceptual morel of structural views? Are they looking down and somehow seeing elements under the floor. Or are they like RCP (but not called this way) and thus expose bearing structure under the floor? In RCP Revit would select a bottom edge.

Tom Weir
2005-02-11, 04:24 PM
Leonid,
<What is really the underlying conceptual morel of structural views? Are they looking down and somehow seeing elements under the floor.>

At least here in Los Angeles where I have done structural work for 23 years we would never use the RCP approach to look up at footings. We produce "floor and foundation plans". We typically cut about 1'-0" above the floor line, and look down. So we usually see the foundation as hidden line below the slab-on-grade.

I see now where you are coming from though in terms of it being a view based function that is tagging what it can see, i.e. the top of the footing.

But this is not a view based decision:
1. Our engineers want to establish that the bottom of footing rests in the proper soil condition as described by the soils engineer.
2. We also need to assure that adjacent footings do not undermine each other. A line drawn from the bottom edge of one footing to the bottom edge of the next footing cannot exceed 45 degrees.
3. You would not believe the convaluted foundation conditions I have encountered over the years. Many times you need both TOF and BOF. It's a fact of life.

So in order to make Revit really flexible it would be very helpful to add that bottom of footing tag capability.

Thanks and have a great day......

Mr Spot
2005-02-13, 11:14 PM
Yes they do. I went to my RCP clicked on spot elevation placed it on a sheet and there it was! I use them all the time. Are you running an old build? Remember I did say to cut below the footing, and look up at it, then you are spot elevationing(if you will) the bottom surface of the footing...

P.S.I just did it on the project I am working on and it worked just fine
Ahh, I guess it's just another one of those fixes they had in the latest build they didn't tell us about. You definitely weren't able to use spot elevations in rcp's previously... We posted it to Martin Taurer as a wish, guess it was granted!!

Should come in handy.

mmodernc
2005-02-14, 08:09 AM
Use 3D View-Top?

mmodernc
2005-02-14, 08:47 PM
hmm if you look at previous post in 3D north or south view and just look it is OK but if you look at it in East or West 3D view and try to mainuplate leader line on the spot elevation it crashes the program.

Michael Coviello
2005-05-04, 10:56 PM
I too would like to see spot elevations working in plan to tag tops of foundations relative to some datum. In my experience and in residential construction, The foundation contractor ONLY has the foundation plan sheet to work with, not the whole set of drawings.
Can revit select the top "plane" of the foundation wall similar to how it selects a wall plane in elevation???

Many times there are so many drops in the top of wall, it would be really useful if this spot elevation was available.