Line Meets Curve

Revit Quick Tip: Toposurfaces Part 3

Welcome back everyone! Today, we will use the surface we created in Toposurfaces Part 2 and add material subregions.

From the Revit Help section:

“Toposurface subregions are regions you sketch inside existing toposurfaces to show different materials and different site objects. They can be used to create conceptual colored site plans. For example, you might use subregions to draw parking lots on a graded surface. You could then apply an asphalt material to the subregion.”

Let’s start by opening the toposurface we created in the previous tip. Open the site plan view so that you can see both the surface and the imported site plan sketch. Select the toposurface and set the material to Site - Grass. We will now begin using the Subregion plan to create regions of different materials. When you click Subregion, you are now in sketch mode. Trace the sidewalk that follows the red property line. In properties, set the material to Concrete.

Now finish the sketch. When you look at your surface in a 3D view, you should see this:

Using the same method, create an asphalt subregion based on the freeform shape on the left side of the site plan. When finished, you should have something like this:

Now we will add a round pond surrounded by sand to the lower right corner of the site. Note that you can have nested subregions but not intersecting subregions. Your site should now look like this:

Hurray! You have now successfully created material subregions. As necessary, you can select an individual subregion to change materials or edit the sketch perimeter. If you delete a subregion, the area will revert back to the material of the dominant toposurface (in this case, grass).

Finally, you may have noticed the building footprint on the site plan. Well, just like DVDs, this Quick Tip comes with bonus features! Let’s learn how to create a building pad. If you have not already done so, you will need to adjust the elevation of your floor plan levels. Since our site plan tells us that we have an entry level at FFE 950′ - 0″ and a main level at FFE 953′ - 0″, we will adjust the default “Level 1″ and “Level 2″ to reflect this. (Remember, you change floor level heights in an elevation view.)

Now that the levels are correctly set to match the FFE of the building, click on Pad to create a pad. The Pad command works similar to the floor command. You will be in sketch mode where you can draw lines or select walls. In Pad Properties, you can set the pad to a particular level and give it an offset. You can also adjust the materials/construction/thickness of the pad just like with a floor. When you create your two pads at FFE 950, and 953′ your site should now look like this:

If you look closely at the pads, you will see that they have depressed the topography within the perimeter of the sketch while the topography outside of the pad remains unchanged.

You have now created material subregions and building pads in your toposurface. Be sure to save your work. It is time to start designing!

If you have any tips you’d like to see or questions you’d like
answered, please submit them here in the comments section or write to
us at lmc@tangentworks.com.

Toposurfaces Part 2

In the Toposurfaces Part 1 Quick Tip, we learned how to create topography in Revit using an imported 3D CAD file. Today’s tip will demonstrate how to create topography by manually entering spot elevations.

So let’s say that you are given a sketch of a site plan and you need to model it in Revit. First, we will import the site plan sketch as a jpg. Since images are imported into a particular view, you will probably want to import this into a site plan view.

I have now imported my image. As with the CAD plan we used previously, I need to verify that my image is scaled correctly. Fortunately, my site plan sketch has a graphic scale on it, so I can select the image and use the resize tool to scale the image correctly–you have the option of using a graphical or numeric scale factor. The resize tool is located next to the Mirror command in the toolbar.

Now that the image is scaled correctly, we will begin our toposurface. From the Site design bar, select toposurface. This time, we will select the Point option. When you select point, you will see a box to enter the elevation of the spot elevation. In this box, enter the elevation from the topo line in the sketch and add a few points along the topo line. The more complex the topography line, the more points you will want to add. When you are ready to add a different topo line, simply change the elevation value in the tool bar. After you enter a point, you can select it and move it or change its spot elevation value as needed.

If you are entering points but you cannot see the points, you may need to adjust your view range. View Range is found in the view’s View Properties window. Set the Top and Cut Plane so that they are above the highest topography line and the Bottom and View Depth below the lowest topography line. You may also need to set the view to Wireframe so that you can see through the topography to the image.

When you finish entering the spot elevations, click Finish Surface to complete the toposurface. Now you can check your surface to make sure it looks correct.

Here is my toposurface in 3D:

Here is my toposurface in section:

You have now created your first Toposurface from spot elevations! Be sure to save your work because soon we will learn how to add material subregions to our toposurface.

If you have any tips you’d like to see or questions you’d like
answered, please submit them here in the comments section or write to
us at lmc@tangentworks.com.

Toposurfaces Part 1

One of Revit’s benefits for us (and by extension, our clients) is the ability for us to model site topography to study its impact on our buildings. To create topography in Revit, we use the Toposurface feature in the Site design bar.

There are two ways to create a toposurface. Today’s tip will focus on using imported CAD data. A future tip will demonstrate how to manually enter spot elevations.

First you will need to import your CAD file. The ideal situation is to start with a CAD file from the client or civil engineer with topography drawn in 3D. Import this file as you would any other CAD file.

*NOTE: As is sometimes common when importing CAD files, you may need to adjust your scale factor.

With the file imported, you can switch to a 3D view to verify that the file imported correctly and that the topography is in 3D. The next step is to create your toposurface. Under the design bar Site select the Toposurface tool.

You will now be in toposurface mode. Select Use Imported - Import Instance and then select your 3D CAD file.

OH CRAP! Revit is asking me to select which layers to use to generate the spot elevations. And I don’t know what layer the topography is on. What do I do now?

If you know which layer(s) the topo is on, select it/them and click OK. If not, we need to backtrack for a second. Cancel this window and cancel your toposurface.

When you select an imported CAD file, several option buttons appear in the toolbar: Delete Layers; Full Explode; Partial Explode; Visibility; and Query. We will Query a topography line to find out various properties, including layer. Click on Query and then select a topo line in the CAD file. The query tells us the topography is on layer 3. (Note that topography lines may occur on more than one layer, i.e. Major Contour, Minor Contour, etc.)

Now we will repeat the steps above to create the toposurface. When prompted, we will instruct Revit to add points from Layer 3. Depending on the complexity of the CAD file, Revit may need a few minutes to process. Remember, patience is a virtue.

When Revit finishes thinking, you will see many spot elevations which Revit has interpreted from the CAD file. If you select one of the spots, you will see the spot elevation value in the toolbar.

(Before we finish our surface, two quick points: the Properties button allows you to select basic properties such as material and phasing. Simplify Surface will clean up the spot elevations to the accuracy you enter. I would be wary of using this function too much as it may oversimplify some particularly complex topography.)

Now we finish the surface. You can now inspect your toposurface in any 2D or 3D view as desired. You will probably want to turn off the imported CAD file in the particular view using Visibility/Graphics control. If needed, you can select the surface to change the material or edit the surface and adjust any spot elevations.

Here is my surface in 3D:

And here is a section thru my surface.

You have now created your first Toposurface from an imported CAD file! Now get Reviting!

If you have any tips you’d like to see or questions you’d like
answered, please submit them here in the comments section or write to
us at lmc@tangentworks.com.