Now it’s official- Autodesk retired the old Toposurface and replaced it with a new category: the Toposolid. In this post, we will go through everything you need to know about this new feature.
So What Exactly Is The Toposolid?
If you know Revit well enough, imagine a Floor and a Toposurface fell in love and had a baby- this would be the Toposolid! We are basically talking about a solid element with Types and parameters where you can add structure layers- very similar to a Floor but with additional Topography capabilities such as contour lines and contour labels.
The Old Site Ribbon:
The New Site Ribbon:
Here Are 10 Things You Need to Know About the New Toposolid
1- What Happens to Old Toposurfaces When You Upgrade a Revit File?
If you upgrade a Revit file to Revit 2024, any legacy topographies will remain unchanged but will no longer be editable. To edit them, you'll need to convert them into a Toposolid by selecting the Toposurface and using the 'Generate Toposolid' command on the Modify ribbon.
Keep in mind that generating a Toposolid will cause any building pads to be deleted, as there are no Building Pads in Revit 2024. It's also worth noting that the old Toposurface will remain in place after the conversion. However, it’s recommended to keep the old surface in the project to make sure the conversion results are accurate.
It's worth noting that you can still create a Toposolid from a CAD or CSV file like before. A useful improvement in Revit 2024 is that surfaces created from CAD files can now have a concave boundary, which eliminates the need for additional splitting that was required in the previous version.
7- No More ‘Split Surface’ - The Familiar ‘Split’ Tool Works on Toposolid (OMG)
One of the best features of the new Toposolid in Revit is that you can now freely cut and split it using the "Split" tool in the "Modify" tab - this is definitely one of my favorite things about the update! However, keep in mind that once you split a Toposolid there is no Merge option like there was with the Toposurface.
9- Turn Off Points When Not in Edit Mode for Better Performance
This is a nice one if you work with complex surfaces which is common in site design projects.
By default, toposolid points won't be visible when you hover over them, unlike how Floors work. However, if you need to see the points all the time, you can easily turn on this option by clicking the small arrow on the Shape Editing panel.
However, in the new Toposolid, this behavior has changed, which may lead to significant discrepancies with the grading that actually happens on the site during construction.
Instead of calculating the volume difference between the top faces of the existing and proposed surfaces, the feature now uses a Boolean operation to calculate the actual difference between the two solids (since now the existing ground is also solid, with its own thickness depending on the used Toposolid type). While the Boolean operation method allows us to calculate the cut volume in cases such as an underground structure, which wasn't possible before, this method was not designed for site grading.
In Revit 2024 earthwork calculation will only work as expected if you use the proper and somewhat tedious graded region workflow, using a Toposolid type with a Variable Material in the Type structure. Any changes made to the proposed Toposolid’s boundary or type throughout the project will result in the wrong calculation.
To wrap up on a positive note, you still can achieve proper grading calculation using third-party applications such as Environment for Revit®.
The Toposolid feature is finally here in Revit, and while it's a great step forward for site design, there's still some functionality missing.