How to Create Toposolids in Revit

A Toposolid is a 3D component that represents the shape and elevation of the site model in Revit with integrated features such as structural layers, hosted elements, cut geometry, and grading regions.

You can create a toposolid by sketching a boundary and adding elevation points, or by importing data from external sources. You can also convert existing toposurfaces to toposolids.

Go to step 4 after starting with one of the first three methods.

As many Revit users have discovered, this tool can be confusing if you are used to the old one.

In this blog post, you’ll learn how to use this versatile tool, and then you can check out the rest of the tips for site plan modeling in Revit 2024.

Method 1 – From Sketch

Details

Create a toposolid in Revit.

This approach provides maximum control and flexibility when designing a new site model.

Steps

1. Go to the Massing & Site tab > Model Site panel.
2. Drop-down the Toposolid menu > click Create from Sketch.
3. In the Draw panel, select a sketch tool.
4. Sketch a closed boundary for the toposolid.
5. Click Finish Edit Mode.

✨ Tip: There are 7 types of toposolids in the Type Selector that you can choose from.

6. Select the toposolid.
7. Go to the Modify | Toposolid tab > Shape Editing panel > click Add Point.
8. In the Options bar, change the value of the elevation.
9. Left-click to add points.

✨ Tip: In the Add Point panel, toggle the Absolute switch. This will keep all new points on a single elevation value.

By default, you don’t see the height points unless you are in Edit mode. To see the points at all times, click the Shape Editing panel drop-down arrow > check Preview Points.

Method 2 – From Imported Data

Details

Import contours from an external source such as a CAD or CSV file.

Steps

1. Go to the Insert tab > Link panel > click Link CAD.
2. Select the file > click Open

Learn more about importing CAD files

3. Go to the Massing & Site tab > Model Site panel.
4. Drop-down the Toposolid menu > click Create from Import.
5. In the Toposolid panel, click Create from CAD.
6. Left-click the toposolid.

7. Check the “Contours” layer to add points from > click OK.

To delete the imported contour and topography layers and keep other site elements:

1. Select the imported object
2. In the Import Instance panel, click Delete Layers.
3. Check the Contours and Topography layers.
4. Click OK.

Method 3 – From Toposurface

Details

Convert an existing toposurface to a toposolid.

Steps

1. Open the Revit file that contains a toposurface.
2. Select the toposurface.
3. Go to the Modify | Topography tab > Surface panel > click Generate Toposolid.
4. Select the base level at which you want to insert the toposolid.
5. Click OK.

After conversion, the toposurface is saved as a “topography” family. You can keep it hidden in your project file to check for inaccuracies in the future.

4- Control The Contour Lines

Contour lines are the lines that show changes in elevation on the surface of the terrain. They can help you visualize the shape and slope of your terrain and also affect how other elements interact with it.

To control the contour lines:

1. Select the toposolid.
2. In the Properties palette, click Edit Type.
3. Under Graphics, click the Edit button of Contour Display.
4. Change the values and subcategories.
5. Click OK.

To change the material and line style of the contours:

1. Go to the Manage tab > Settings panel > click Object Styles.
2. On the Model Objects tab, click the plus sign next to Toposolid to expand the menu.
3. Change the line weight, style, and object material.
4. Click OK.

This changes the visibility settings for all views. To change how the lines appear in a view, use the Visibility Graphic Overrides settings (shortcut: VV).

5- Split The TopoSolid

The Split feature allows you to edit or delete smaller sections or regions of terrain. This allows you to have different layers for different areas of the same topography object.

To split your toposolid:

1. Go to the Modify tab > Modify panel > click Split Element.
2. In the Draw panel, select a tool to draw a split area.
3. Draw the lines that will divide the topography.
4. Click Finish Edit Mode.

Learn more about the split tool

6- Make Subdivisions To Divide Surface

Subdivisions are a positive offset from the original terrain. They are useful for creating landscapes and features on the site.

Sketch lines, arcs, and shapes can be used to add a separate face to a toposolid, making it easier to create curbs, streets, and islands.

To make subdivisions:

1. Go to the Modify | Toposolid tab > Toposolid Shaping panel.
2. Click Sub-Divide.
3. Select the toposolid.
4. In the Draw panel, select a drawing tool.
5. Draw the enclosed shape that you want to split from the main toposolid.
6. Click Finish Edit Mode.

And then it’s possible to change the material or height of the subdivision:

1. Select the subdivision.
2. In the Properties palette, click the prompt box of Material.
3. Change the value of the Sub-divide Height.
4. Click Apply.

✨ Tip: Check “Inherit Contour Lines” to keep the contour lines visible after you apply changes.

7- Add Layers

Add layers of soil, rock, sand, gravel, etc. to your toposolid.

Structured layers represent the composition of your terrain and can help you create more realistic and accurate site models and affect how other elements interact with it.

The process of changing the layers of a toposolid is the same as for floors:

1. Select the toposolid.
2. In the Properties palette, click Edit Type.
3. Click “Duplicate” to make a new toposolid family.
4. Under the Construction section, click the Edit button next to Structure.

✨ Tip: Duplicating a component’s family prevents the changes from being applied to the entire project.

✨ Tip: Use a section box to see the layers of topography as you apply them.

8- Make Voids

Voids are empty spaces that are subtracted from your terrain. The cuttability of toposolids is the replacement of building pads and an improvement to how the topography component is affected by other elements such as Floors, Ceilings, Slab Edges, Wall Sweeps, Mass, Void forms, and more.

Toposolids increase the speed and workflow efficiency of modelling embedded and underground structures.

To make voids in your toposolid:

1. Go to the Architecture tab > Build panel.
2. Drop-down the Component menu > click Model In-Place.
3. Select “Toposolid” as a family category.
4. Name the new family > click OK.

5. Go to the Create tab > Model panel.
6. Drop-down the Void Forms menu > click Void Extrusion.
7. In the Work Plane panel, click Set Work Plane.
8. Select the plane parallel to your desired void surface.

9. Move the view cube to the side parallel to your desired surface.
10. In the Draw panel, select your preferred drawing tools.
11. Draw the enclosed profile of the void(s).
12. Switch the view cube to a 3D View mode.
13. Click Finish Edit Mode.
14. Grab and drag the shape handles to complete the void form.

15. In the Geometry panel, click Cut.
16. Select the Void form, and then select the toposolid.

Learn more about cutting geometry

✨ Tip: To select a hidden void element, move the cursor near the applied void and press TAB several times to toggle between visible and invisible elements. Select the void when it’s highlighted in blue.

9- Host Elements

Hosted elements are elements that are attached to the surface of your terrain, following its shape and elevation.

To make it easier to see elements as you add them to the host, change the visual style to “Consistent Colors” from the View Control bar.

You can add trees, plants, rocks, furniture, etc. to your Toposolid. Here’s how to load more families:

1. Go to the Insert tab > Load from Library panel > click Load Autodesk Family.
2. Browse your desired category.
3. Check each family to be loaded.
4. Click Load.

Learn more about loading families

5. Go to the Architecture tab > Build panel > click Component.
6. In the Type Selector, select the family.
7. Left-click to place the family on top of the toposolid.

Hosted elements can help you create more realistic and detailed models of your terrain and also affect how other elements interact with it.

The previous steps result in an improved workflow for designing both artificial and natural 3D landscapes. They allow you to create realistic and detailed models of hills, valleys, lakes, roads, bridges, and more.

The next steps are to manage the topography and its volume.

10- Grade Regions for Phasing

You can use the Graded Region feature to suggest a variety of site designs with different elevations of the points.

It is mainly used to grade some areas for temporary or permanent purposes, for drainage or erosion control, for accessibility or aesthetics, etc.

To grade regions:

1. Select the toposolid.
2. In the Properties palette, change the Phasing properties to Phase Created: Existing, and Phase Demolished: None.
3. Go to the Massing & Site tab > Analysis panel > click Graded Region.
4. Click “Create a new topography exactly like the existing one”.
5. Add or adjust voids and points for the grading.

Learn more about phasing

In the example above, you can see how the voids were filled. Next, you’ll learn how to track and report cut and fill volumes with a Toposolid schedule.

11- Cut and Fill

A feature that allows you to calculate the amount of earthwork required for a site project. You can use it to compare the existing and proposed topography of your site and generate a report of cut and fill values.

To perform cut and fill calculations:

1. Go to the View tab > Sheet Composition panel.
2. Drop-down Schedules menu > click Schedule/Quantities.
3. Select “Toposolid” in the Category field.
4. Click OK.

Looking for more information on schedules? Our guide to calculating areas will take you through the process step by step, and then we have another tutorial to show you how to export your Revit schedules to Excel!

✨Tip: The graded region copies the current topography into the current phase, which in this case is “New Construction”, so in order for the cut and fill to work, you must set the Toposolid into a previous phase, such as “Existing”, before starting the calculations.

That’s it! We hope this blog post has helped you learn how to create Toposolids in Revit using different methods and tools.

Mohamed Fakhry

Mohamed Fakhry has helped thousands of architects and designers find their next project with step-by-step guidance on his blog, mashyo.com. About Mohamed

His journey began during his university years when he recognized the need for information-rich 3D models to accelerate learning and improve production processes. Now, Mohamed shares his expertise through Revit tutorials that are accessible to all.