In Autodesk Revit, when demolished walls or other elements from a linked architectural model are missing in the host model, the issue typically lies in phase inconsistency between the host and linked models. The architectural model may include elements created or demolished in phases that do not exist or are mismatched in the electrical model (the host). To resolve this, Revit allows users to map phases between the host and linked models through the Phase Mapping tool in the link’s Type Properties dialog.
According to the Autodesk Revit MEP Electrical Design Guide (Linked Models Section, pp. 1282–1287), the official procedure is:
“You can manually set up a correspondence between phases in the host model and phases in the linked model. To do this, you set up a phase map in the properties of the linked model, and then apply the phase map in the host model.”
(Revit MEP User’s Guide, Chapter 53 – Linked Models, p. 1282)
The step-by-step process is precisely described in the Revit documentation as follows:
To map phases in the linked model:
In the drawing area of the host model, select the linked Revit model.
Click Modify | RVT Links tab ➤ Properties panel ➤ Type Properties.
In the Type Properties dialog, find the Phase Mapping parameter and click Edit.
In the Phases dialog, select the appropriate mapping options for each phase, and click OK.
Click OK to exit the Type Properties dialog.(Revit MEP User’s Guide, p. 1287)
This procedure ensures that demolished or existing architectural elements display correctly according to the electrical model’s phase structure. Without this mapping, Revit cannot interpret which linked phase corresponds to the host’s “Existing” or “New Construction” phases, causing certain geometry—like demolished walls—to disappear from view.
Supporting Extracts from Revit for Electrical Design Study Documentation:
“To modify the type properties of a linked model, select the linked model in the drawing area, and click
Modify | RVT Links tab ➤ Properties panel ➤ (Type Properties).
The Phase Mapping parameter allows you to set up a correspondence between phases in the host model and phases in the linked model.”
(Revit MEP 2011 User’s Guide, p. 1305)
“When you link a Revit model that has more than one phase, phases in the host model automatically map to phases in the linked model. When this initial mapping occurs, Revit maps phases by matching phase names.
You can manually set up a correspondence between phases in the host model and phases in the linked model using the Phase Mapping function.”
(Revit MEP 2011 User’s Guide, p. 1282)
“If phase-specific elements in a linked model do not reflect correctly, check phase mapping for the linked model. If automatic mapping does not give the desired result, map phases manually between projects.”
(Revit MEP 2011 User’s Guide, p. 710)
Conclusion:
Therefore, to fix the issue where demolished walls are missing in a linked architectural model, the electrical designer must perform manual phase mapping between the architectural model and the host electrical model. This is done by selecting the linked file, opening its Type Properties, and editing the Phase Mapping parameter.