Understanding of HVAC Efficiency Ratings
May 8, 2025
Revit Phasing
Revit Phasing is a powerful feature that allows users to manage a project’s timeline by organizing building elements into distinct stages, making it an essential tool for projects involving renovations, additions, or multi-stage construction. At its core, phasing enables you to define when elements exist within the lifecycle of a building—whether they’re part of the existing structure, slated for demolition, or newly constructed. This temporal organization is paired with phase filters, which control how these elements are displayed across different views, ensuring clarity and precision in design documentation. Together, phases and phase filters provide a structured way to visualize and communicate a project’s evolution, from concept to completion.
Understanding Revit Phases:
In Revit, phases are created and managed through the “Phases” dialog box, accessible under the “Manage” tab. By default, a new Revit project starts with two phases: “Existing” and “New Construction.”
However, you can add as many custom phases as needed—such as “Phase 1 Demolition,” “Phase 2 Renovation,” or “Future Expansion”—to reflect the specific timeline of your project.
Each phase has two key properties:
- a “Phase Created” value, which defines when an element is introduced, and
- a “Phase Demolished” value, which marks when it’s removed.
For instance, a wall modeled in the “Existing” phase with no demolition assigned persists throughout the project, while a wall demolished in “Phase 1” disappears in later stages. This system allows you to assign every object in your model—walls, doors, furniture, even annotations—to a specific phase, creating a chronological framework for the design.
The beauty of phasing lies in its flexibility. Imagine a renovation project: you can model the original building in the “Existing” phase, tag walls or windows for demolition in “Phase 1,” and add new elements like modern partitions or HVAC systems in “Phase 2.” Revit automatically tracks these assignments, so when you switch between phases in a view, the model updates to reflect only the elements relevant to that stage. This is especially useful for generating phase-specific drawings—like an “Existing Conditions” plan or a “Demolition Plan”—without needing separate models. It’s a time-saver for coordinating with contractors and stakeholders, ensuring everyone understands what stays, what goes, and what’s coming next.
Diving into Phase Filters
Phase filters work hand-in-hand with phases to control how elements are displayed based on their phase status relative to the view’s active phase. Each view in Revit has a “Phase” setting (e.g., “New Construction”) and a “Phase Filter” setting (e.g., “Show Previous + New”), which together determine what you see.
Revit provides several default phase filters, but you can customize them to suit your needs. These filters evaluate three categories of elements:
- By Category – elements shown as they’re typically styled
- Overridden – elements with modified graphics
- Not Displayed – elements hidden entirely
The filter’s behavior depends on whether an element is “Previous,” “Current,” or “Demolished” relative to the view’s phase.
Let’s break down the default filters:
- Show All: Displays all elements from all phases, with existing elements in gray, demolished elements in red dashed lines (if overridden), and new elements in solid black. This is great for an overview but can get cluttered.
- Show Previous + Demo: Shows elements from prior phases plus anything demolished in the current phase—perfect for demolition plans.
- Show Previous + New: Highlights existing elements and new construction, hiding demolished items—ideal for progress drawings.
- Show Demo + New: Focuses on what’s being removed and added in the current phase, useful for construction sequencing.
- Show New: Displays only elements created in the current phase, excluding anything existing or demolished—handy for isolating new work.
- Show Complete: Displays all existing and new elements up to the current phase “By Category,” hiding demolished items—great for showing the project’s cumulative state, like final as-built plans.
- Show New: Shows only elements created in the current phase “By Category,” excluding existing and demolished—perfect for isolating new work, like phase-specific construction drawings.
In the end of this document I have explained all this Phase filters with examples for the better understanding.
You can customize these filters in the “Phase Filters” tab of the Phasing dialog. For example, you might create a “Show Existing Only” filter to isolate the original building or tweak the “Overridden” settings to change how demolished elements appear (e.g., blue dashed lines instead of red). Graphic overrides, set in the “Phases” dialog under “Graphic Overrides,” let you further refine this—adjusting line weights, colors, or patterns to differentiate phases visually.
