A strange question for elevation at top & bottom

[wang_yilin]

Recently, we find a strange~

usually we create a new revit model and model a slab on Level 1;

for that slab, it has two parameters named " elevtation at top" " elevation at bottom ", shows in the pic. below~

However!! in one model which we get from another company, it changed, and we don't know the reason..

how does the 2nd situation  happen??

[ennujozlagam]

@wang_yilinhello, check the level between the two they are totally different. thanks

[ToanDN]

What is the elevation of FFE level?

[wang_yilin]

I know they r different

because they r not the same model~

first snap shows the general situation in Revit

Second snap shows a different situation whose model created by another company~

[wang_yilin]

forget about that, because they r not the same model~

I just wanna know why would the second situation happen, because it is created by another company, and now I could not ask them for answer~

[ToanDN]

Forget about what? I am asking you a question in order to understand the issue.

[ennujozlagam]

it could be your project base point elevation. thanks

[wang_yilin]

yeah, i agree;

but in which condition may cause this problem~ i don't now, and I wanna know how to modify that correctly

[wang_yilin]

sorry

what I mean is the two snaps upside are two different model~

the second model is wrong~ and I don't know the reason why could that happen....

[ToanDN]

Then what is the elevation of the FFE level?  Go to an elevation and post a screenshot.

[wang_yilin]

u could just consider that FFE. Level as Level 1

[ToanDN]

I sure would if you posted a screenshot of an elevation showing the level.  Is it that difficult to do?

[ennujozlagam]

Check between two files, go to levle1 or site plan > go to VG > model categories > site > tick project base point and compare elevation betwen the two files. thanks

[wang_yilin]

Sir， Elevation View like this, the snaps upsides create in 3D VIEW~

[wang_yilin]

I have already check the Project base point~ but what makes me feel confused is why it would affect the parameter " elevation at top", I don't know the reason~

[ToanDN]

Thank you!  Can you share the file?

[wang_yilin]

thank u~ but I could not have a proper way to share my model~

[chrisplyler]

Because a Slab's Elevation at Top value is based on the Project Base Point.

So your F.F.E level is 149mm above the Project Base Point.

Level type is probably set to be relative to Survey Point so that's why it reads 0 instead.

[Alfredo_Medina]

Hello, @wang_yilin , welcome to the forum. 

The spot elevation tool has a parameter called "Elevation origin". This can be set to read the elevation from the Project Base Point or from the Survey Point, depending on the preference of the office or project managers.

So, you can have 2 types of Spot Elevations, pointing at the same slab, and both of them can show different elevations.  This is normal, it's not an error.

Suppose I have 2 slabs in the same project, where the project base point has an elevation of 149. Then I tag one slab with the Spot Elevation (Project) type and the other slab with the Spot Elevaton (Survey) type. The results will be as shown in these images. This is the elevation or section view:

And this is the plan view:

[wang_yilin]

sir, u could see the elevation snap, it shows the F.F.E Level shows 0, not 149