HELP! Large model performance is extremely poor. Need strategies to improve it.

[cristinaroldan]

Hi there,

We are working on a big project, two highrise residential towers. Our architectural model is saved in BIM 360 and it is currently 2.3GB. We have two models linked. We are almost done with the first tower and starting the construction phase of the second tower. 

Our company creates the documentation on a architectural design level, plus general constructor level and also shopdrawigs for import orders, so we have many many views and sheets in the model.

I am looking for ideas, tips or strategies on the direction we should take to make our work more efficient. Currently the model is extremely slow even for the simpliest task like drafting. Strategies used already: remove all the working views, purge the model, audit, close unused worksets, rename the model and upload it to BIM 360...While all of these helps a bit, the performance is still very poor. Anybody else in the same situation? What did your firm do to make your large model work efficiently?

Thanks in advance, any ideas are trully appreciated!

[RSomppi]

We are nearing the end of a large project that I have gone through all of those with similar results. They help but didn't quite get us there. The last thing I tried was splitting up the model into two. In hindsight, I would have split it into four in the beginning and did as much documentation in a separate model but I feel that utilizing separate models was the best fix.

[cristinaroldan]

Thanks for your response 🙂 We are also considering to split the model but we are not sure what will happen will all the views and sheets related to the componets of the linked portions. Where you able to keep all the sheets and views? Are there any things you did that were specially helpfull during the splitting process for you? Thanks again! 

[RSomppi]

It was a simple "Save As" and then delete elements, our sheets stayed intact. I say "simple" but I took extreme care to make sure I didn't delete the same elements from both models. A little extra care is necessary to keep the sheets coordinated. We also do prefab and the assembly sheets workflow required altering some to prevent duplicate sheets numbers. Manual vs. automatic.

[cristinaroldan]

Oh I see. I was thinking on doing the split of the model by grouping elements and then linking. I can see how your method could be of use as well. Thanks for sharing the tips. Glad it worked for you 🙂

[barthbradley]

https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/Revit-Slow-Perform...

https://www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/Revit-file-mainten...

[Niko_Davydov]

Hi @cristinaroldan ,

you can divide the model into facade, furniture, building, and landscape. Additionally, the building model can be split into different worksets – for example, into structural shell, drywall, etc., or assign each floor to its own workset.
Warnings in Revit also have a significant impact on performance. It’s important to always try to reduce them. We had a project where these errors severely slowed down work in Revit until we fixed them.

Best regards,

Nikolai Davydov

[cristinaroldan]

Hi there! thanks for your response. We already have the model separate into facade, structure, and architecture..the arch model is the one we might need to keep spliting. As for the warnings, thanks for the reminders. We actually have way too many of those, we will work on reducing them.

[Niko_Davydov]

Also, as an idea, you could have a separate file for details. You can link all your models into that file and create 2D details only in this specific file.

[TripleM-Dev.net]

Hi @cristinaroldan,

The 2.3GB is that the Model itself or if downloaded from BIM360 including all links in it?

Might be worth to check what's making the model that big.

In my experience is that views don't increase it a lot, a lot of 2D annotation (detail items, lines etc) may make the views heavy. Keep in mind that a Group placed x-times also makes the model x-times larger it's just easier modifying.

If there's a lot of 2D items / detail groups, making/using families may make the model smaller.

Also having a lot of families with 1 type in increases the file more than 1 (parametric) family with more types.

Other items to look for:

- Purge, can items (groups, unused families) be purged?

- Model inplace families (very inefficient elements, if used a lot consider making them parametric families)

- Same for inplace massing

- Check the warnings, may also indicate some issue.

- Audit and/or compact the model (no save-as needed)

- High detailled families (specially downloaded manufacture families can be over-modelled) and make the model large and slow.

- Maybe export all families from the model (File > Save-as > Library > Family) and see how large the families are.

   (I once recieved a model with a Rail emplacement family, which was 2Gb, it had tons of nested families, in which all families also were nested x-10, and all unshared. After purging every nested family I ended up with a family of 3Mb)

As reference, any family above 2Mb will need review. I Use several larger ones but they are made up from shared nested families.

- Edit in place may also be a likely candidate, or complex floor/roofs with a lot of modified subelements

- Topo?

- A lot of worksets?

- Large linked Dwg's or even imported ones?

etc...

But first thing I would do to investigate is; make a copy off BIM360 and run a eTransmit (under Add-Ins) on it, and turn options on like Delete all views/sheets, purge etc. and see how large it is then. Before splitting up a model (you lose a lot of references to elements, lilke tags/dimensions)

I hope it may be of some help, large slow models are no fun to work with.

- Michel

[casandraarmeanu]

Hi @cristinaroldan, here are some additional steps you can take to improve the model's performance:

1. Upgrade to newer Revit versions: from our tests made on different projects saved in Revit 2021 or 2022, after upgrading to Revit 2025, the model open time was reduced with almost 50% in some cases. 
2. Use the option “Compact Central Model” when sync with central at least once a month.
3. RVT Links management: from our internal tests, we discovered that the total model open time is approx. the sum of opening time of each link. Some suggestions you can try:

• place the links on separate worksets (maybe a group of links on a separate workset) and choose which worksets to open when opening the model, then open the other worksets only when needed. 
• limit the number of nested links and circular links (link references itself), to prevent additional loading time.
• when using live linking, if a link is changed, a new version has to be downloaded every time the host model is opened. This can increase the open time significantly if a lot of links need to be downloaded each time. What you can do:
  •  install the latest version of PAC (v24.4.14.0). The latest version increases the number of cloud models PAC manages by default to 200 and includes several performance improvements (download and install it from https://manage.autodesk.com/products/updates, search for Revit Personal Accelerator). Revit Personal Accelerator FAQ
  • adopt Shared/Consumed workflows for cloud workshared models

4. Linked non-RVT files (.dwg, .jpg, .pdf):

• pre-process the DWG file in AutoCAD to import a simplified file. You can try deleting unnecessary parts and layers like hatching or AutoCAD-specific linework such as construction lines.
• rather than using large pictures, choose a more compact, reduced version for importing.

5. Review and remove Plan Regions: check for plan regions, as they can cause performance issues. Delete unnecessary plan regions or remove the sketch geometry, especially if they appear in review warnings.
6. Address overlapping rooms: check for overlapping rooms and remove any unnecessary or duplicate/redundant rooms, areas, or spaces to optimize performance.
7. Many views opened: opening many views can fill up memory, the memory is not cleared when closing the view, only when closing Revit.
8. Missing external references: check for missing files, such as keynotes, images, PDFs, links. For each attachment, Revit checks if the file is available and retries the process several times. If a file is on an unreachable network location or linked from a local user folder, it can significantly impact model open time.

Please let us know if you find these suggestions helpful. Thanks 😊