It is time to add some recesses. We have got a model from the ventilation company which we are going to use as a reference for adding the recesses. 

Find the ventilation model here.

From the 3D view, go to Insert - Link - Link Revit and find the ventilation model. Click 'Open' to link the model. 

Figure 1. Link the ventilation model.

The model contains two ventilation pipes that are cutting through one of the solid walls. We need to add recesses for this wall. 

Figure 2. Ventilation pipes are cutting through the wall.

To easily place the recesses we need to prepare a working section that we can place in front of the wall. 

From the 'Level 1', go to View - Create - Section and place a section like in Figure 3 below. 

Figure 3. Add a working section.

The section will be available in the project browser after being added to the model. Go to the section.

Figure 4. Section view in the project browser.

The section will look messy the first time we open it due to scale and so on. 

Figure 5. New section views will look messy.

To clean it up, we need to switch the scale to 1:20, adjust the size of the section view, change the visual style to 'Shaded', and change the level of detail to 'Fine'. See Figure 6 below.

Figure 6. Clean up the section view.

The section is prepared and we are ready to add the recesses. 

Go to IMPACT - Components - Draw Recess to start the command. 

There are two types of recesses to use: standard (1) and user-defined (2). 

The standard recess can be added as rectangular or circular. The size can be selected from the drop-down list (3), or entered manually (4).

The shape of the user-defined recess is controlled by model lines that the user draws on the surface of the host. This will be used later in the course. 

Figure 7. Draw recess dialog.

Since the ventilation pipes are circular, we are going to use the circular standard recess option. The left pipe is Ø300mm and the right pipe is Ø170mm, so we make the recesses Ø320mm and Ø190mm so that there are some tolerances.

There are no circular recesses with these dimensions, so we key in the size. Select 'Cut out' as recess depth to make sure that the recess goes through the wall. 

Figure 8. Draw recess Ø320mm.

When placing the recess, it's not that easy to pick the exact center point from the linked Revit model. Instead, place the recess next to the pipe and use the align tool (Modify - Modify - Align) to place it properly. See Figure 9 below. 

When using the align tool, select the point where you want the recess to be moved and then select the center point of the recess. 

Figure 9. Place the recess with the align tool.

Repeat the process for the right recess.

We don't need the linked ventilation model anymore. In the bottom of the project browser, you can find 'Revit Links'. Expand that node, right-click on 'MEP project' and click 'Unload'. The model will disappear, but you can load it back later if you need it. 

Figure 10. Unload linked Revit model.

Next: Add Reinforcement