Aligning Vectorworks and Revit Models for BIM (for (almost) beginners)

[Jack2022]

Hi All,

 

after much pain and suffering trying to find out how to do it I thought I would share how I align my VWs models with lead consultant's (Architect's) Revit model. This assumes the following:

• You are not lead consultant so you haven't created the shared project coordinates yourself.
• You are not lead consultant so you are contractually obliged by your client to align your model with the lead not the other way round
• You are not the BIM coordinator and have received a useless Revit centric BEP.
• You understand the difference between User Origin and Internal Origin in VW.
• You understand the importance of modelling close to the Internal Origin to avoid glitches
• You are doing this before you start modelling. While the steps are the same for after you've modelled, changing the Internal Origin is not advised unless you are being held at gun point by the client. All your sheet layer viewports will be messed up and need reworking. 

 

Key message: you need to change the coordinate of your Internal Origin to match the Internal Origin of Revit (which should also be the shared project coordinate). Forget User Origin for now.

 

Steps:

 

1. Ask the lead consultant (or whoever has set the shared project coordinates) for the Northing and Easting coordinate (relative to British National Grid or your local system) for the Revit Internal Origin. Revit does not recognise your VW User Origin so changing the User Origin won't help align models.

2. Firstly make sure your Vectorworks Document is set to your local coordinate system:

• File> Document Settings>Georeferencing>tick 'adjust origin and orientation of georeferenced data to match document coordinates' (not sure if necessary).
• in this window check 'Use an EPSG code or CRS name'
• Click Lookup and find EPSG 27700 / CRS name: OSB 1936 / British National Grid (or your local system). I had to Google this. 
• Close Document Georeferencing window. This makes sure you are in the correct overall system for Northing and Easting coords (if in the UK).

3. If you now go to your Geolocate tools and select 'Geolocate' while looking near your Internal Origin VW will download and display a satellite image of the world at your Internal Origin. For me this was default right next to the Greenwich Observatory in London. You want your project site to appear here instead in exactly the right location to the mm so...

4. De-select the Geolocate tool (this step was just to demonstrate the location of your Internal Origin in VW relative to the real world).

5. Draw a circle anywhere and type into its centre point properties the Northing and Easting of the Revit Internal Origin. 

6. Select the Geolocate tool again and click on the centre of the circle. You get a warning that this changes the Internal Origin of VW but accept it anyway. 

7. Now your Internal Origin is the same as the Revit Internal Origin and should be in the 'real' site location. Assuming the Revit user knows what they are doing.

8. Select the Geolocate tool again and hover over the Internal Origin - it should download the satellite image of the real location which should be your site. This step is just to check everything has worked and is not necessary.

9. Head to Tools>Origin>User Origin> check 'Set User Origin to Match the Georeferencing coordinate system'. This just makes sure your User Origin is reset and providing you real coordinates if you have been moving it in the past. 

10. Celebrate. 

11. if the Revit using lead consultant has also rotated their Internal Origin I am pretty sure you can do so too by heading back into File> Document Settings>Georeferencing and changing the angle to true north here. Edit: the Geolocate tool has a setting option to rotate the Internal Origin.

 

I don't know if it is possible to also change the Z height of the VW Internal Origin but it is less important. Revit seems to struggle with moving IFC models into position manually in the X Y plane but moving it in the Z axis is a relatively simple task and the Revit using lead consultant shouldn't break a sweat over it. I only share my model as IFCs to Revit as you get control over what to export.

 

It is important to make sure your User Origin is set to Northing and Easting 0,0. This ensures you get proper coordinates from your model and you import references in the correct position but also for file sharing across multiple softwares. While Revit only recognises Internal Origin, Autocad and Navisworks seem to use your User Origin when importing.

 

Hope that saves some of you your sanity. 

 

Jack

 

Edited November 11, 2022 by Jack2022

[zoomer]

I do the same.

 

Just that I renounce of your # 9.

 

1 hour ago, Jack2022 said:

check 'Set User Origin to Match the Georeferencing coordinate system'.

 

As I do not care about the "world" coordinates but want my drawing center 0,0,0

at the building grid start.

[Jack2022]

1 hour ago, zoomer said:

I do the same.

 

Just that I renounce of your # 9.

 

 

As I do not care about the "world" coordinates but want my drawing center 0,0,0

at the building grid start.

Good to know. 

 

on point 9 - you must be an architect!

[Christiaan]

On 11/11/2022 at 5:09 PM, Jack2022 said:

You are doing this before you start modelling. While the steps are the same for after you've modelled, changing the Internal Origin is not advised unless you are being held at gun point by the client. All your sheet layer viewports will be messed up and need reworking. 

I've just done this and it's not as bad as I thought it would be.

[Kian]

@Jack2022 Really appreciate the time taken to write this out. Although I am a bit confused on something.

 

When you use the circle method to type in the coordinates for the internal origin, why not just change the coordinates in the georeferencing dialog box to match the Revit ones? The reason I'm asking is because I tried to coordinate a model with Revit using the dialog box and it didn't work before, I just don't understand why?

 

I can't wait for this to click but I've been going over all available info for months and still twisted up!

[Jack2022]

Hi Kian,

 

This was written for VW 2022 - but I see now 2024 allows you to input N/E coords in Geo referencing menu! Saves steps from above. 

 

 

[loic.jourdan]

Hi Jack, 

 

Just wanted to say thanks for taking the time to write this out, your instructions were super clear and very easy to follow. 

 

Have you had any feedback from architects, BIM co-ordinators or other disciplines from using this process? No feedback is probably good news anyway but just wanted to see if you'd had anyone comment on whether or not this works as well as Revit files referencing into each other?

 

I've had a few issues now with Revit users commenting on VW files not automatically taking the coordinates/project north from their model and that they have had to manually move them to fit. I will be using your process on my next big project to see if it rectifies the issues I've been experiencing! 

[Jack2022]

Hi,

 

Ever since following these steps i've not had an issue with Revit users. The VW model imports correctly their end - but you need to set the VW 'User Origin' coord to match the georeferencing system before you do (last option below): you can change back after to suit - user origin is a movable/ flexible thing and doesnt affect the core set-up of the file. 

 

 

You also need to make sure you change angle to true north to match the Revit user's set-up (assuming they are lead and you follow their set-up). This depends on whether they have a false north. This was a bit of trial and error for me as depends which way round the degree arc they've gone but becomes obvious if you have an auto cad Topo survey in correct position. If the Revit model is already orientated to true north then no problem. 

 

Lastly VW (as far as I can tell) doesnt allow you to have a false Z value whereas Revit users often have this. In this case I tell them it's as simple as clicking on our model and giving it a Z value as required. This is easy if the model is otherwise in the correct location. 

 

So in simplest terms you need from the Revit user:

 

• Their Internal Origin Coord location (dont accept alternative terminology about base points etc. often they dont understand what you're asking if not the BIM technician).
• Angle to true north.

 

Regards,

 

Jack

 

[Thomas W]

Hi everyone and thank you very much @Jack2022 for these explanations which worked well after a few tests.

 

When exporting to Ifc the altitude of the project in Z was taken into account in relation to the heights of the floors and the Ifc could be linked correctly in Revit.

 

Thanks again for these instructions!

[Jack2022]

Thanks Thomas - will consider floor /level heights as the Z base value on the next one. 

 

 

[Thomas W]

If this helps anyone:

 

Since the convention required having all the surveyor levels, I created 1 floor per level to find them in an Ifc viewer.

 

Floors in Vectorworks:

 

 

 

Exporting layers by floor during Layer Mapping:

 

 

The requested levels are found by opening the Ifc file in a viewer:

 

 

Have a nice day

 

[Chris J Clarke]

Thanks for posting this. I've been battling all day to get this working on a project. I got the Coordinates for the site from the Lead BIM Manager at the Client Offices.

 

E/W - 529808876.6

N/S - 180310450.2

True North - 328.93

 

Vectorworks wants these in metres due to SPSG 27700 being a Metres Standard. So I enter the numbers with a 4 decimal place adjustment, and it rounds up the last bit on the Northing and Easting to the following:

 

Easting (X) 529808.877m

Northing (Y) 180310.450m

Angle to True North 328.93000000

 

I'm not sure if that matters. It does come up at the right place on the Geoimage Tool. I can also import the Shared Coordinates File, and it lands in the right place with the right location, I think...

 

The problem now is that whenever I import a Revit from the various BIM guys doing the Plant and Ceilings etc, they just land with the wrong rotaion. If I go into Revit 2021 (The one they're all using) and export to a DWG, I get the option in VW export options to enable Georeferencing for the import., You don't get that option with a Revit import. Does someone know if it's possible to import a Revit to land in the right place please? It must be something I'm doing wrong.

[Jack2022]

Hi, 

 

To point 1:  I suggest it doesnt matter. The coords you've received are 0.6 and 0.2 of a mm which is an odd thing to need unless you're working for Space X.

 

Point 2: I've found angle to true north from Revit users is usually the inverse to what we use in VW. So for you it is 360-328.93= 31.07. This might solve the issue of their model not arriving in the right place. I usually import a georeferenced 2D dwg layout which always comes in correct to check.

 

Hope that helps. 

 

 

[Chris J Clarke]

Thanks for your reply. Yeah I agree that it probably doesn't matter most of the time. I wouldnm't usually bother, but on this one I have to sync our model with a system called Revitzo. It detects clashes, so being off by that much might trigger a clash detection. I'll know when I can work out how to actually sync what I have to Revizto. Honestly, this project has gotten beyond what I know, and I'm in over my head now. Until I can get the Revit models we're recieving to land in the right place, I can't risk syncing what I have. If it lands in the wrong place in Revizto, I'm not sure what to do next.

[Thomas W]

Hi, I just saw your message.

 

1. In the BIM convention that I had the coordinates were also with 4 decimal places, they were also rounded to 3 decimal places in vectorworks but this did not create conflicts in the model.

 

2. After an exchange with the Bim manager I provided them with 2 Ifc files, 1 with the angle relative to north which fits without problems with the other models in an Ifc viewer, 1 with an angle at 0° that the Bim manager inserted in Revit.

(I suppose it came from their settings in Revit since in an Ifc viewer it is inserted in the right place)

 

I hope you can resolve your differences. 

 

Have a great day.

 

[Chris J Clarke]

@Jack2022 You were right about inverting the True North Coordinate. Thank you for that one. The models are now coming in to the right place.

 

That's a good shout. I haven't seen anything about that anywhere else, so you might well have saved me a great deal more stress.

 

Thanks again.

[Jack2022]

Also with clash detection the BIM manager usually sets a degree of tolerance according to discipline. For engineers it's a small tolerance, for landscape usually higher - can be as much as 50mm as most items are not critical (obviously some are but it gets rid of most clashes). I wouldn't expect any to be set less than 1mm. 

 

Glad positioning is resolved.