Phasing in Revit: Managing Demolition, New Construction, and Project Timelines

Construction projects rarely happen all at once. A hospital might be built over five phases to maintain operations throughout. A housing development might be consented and financed in tranches. An office refurbishment might need to be sequenced around a live tenant fit-out. Even a relatively simple residential extension involves at least two states: what’s there now and what will be built. Revit’s phasing system provides a structured way to represent all of these temporal states within a single model, producing phase-specific drawings and schedules without duplicating geometry.

This guide goes beyond the basics of existing versus new construction to explore the full capabilities of Revit’s phasing system: creating multiple project phases, managing phase filters and graphic overrides, handling complex demolition sequences, and using phases for construction programming information.

Autodesk Revit is available from GetRenewedTech for £39.99.

The Core Concept: Phase Created and Phase Demolished

Every element in a Revit model carries two phase parameters: Phase Created (the phase in which the element came into being) and Phase Demolished (the phase in which it was removed, if applicable). These two parameters, combined with the phase setting of each view, determine what is shown and how it’s displayed.

This is a fundamentally different approach to time management than maintaining separate model files for each phase. In a file-based approach, coordinating changes across multiple files is manual and error-prone — any update to a structural grid, for example, needs to be replicated across every phase file. In Revit’s single-model approach, structural grids exist once, and every phase view reflects them automatically.

Setting Up Your Phase Structure

Phase management begins in Manage > Phases, which opens the Phasing dialogue. Here you’ll see the Project Phases tab, which lists all defined phases in chronological order. By default, Revit provides two phases: Existing and New Construction.

Adding Custom Phases

To add phases, click in the Phase list and use the Insert Before or Insert After buttons. Name each phase clearly and descriptively. For a phased residential development, you might have:

• Existing
• Phase 1 — Enabling Works
• Phase 2 — Residential Block A
• Phase 3 — Residential Blocks B and C
• Phase 4 — Community Facilities
• Phase 5 — Landscaping and External Works

Phase order matters. Revit treats phases as sequential, and the system assumes that later phases build on earlier ones. You cannot assign a Phase Demolished value that precedes the Phase Created value — an element can’t be demolished before it was built.

Phase Filters

The second tab in the Phasing dialogue is Phase Filters. Phase filters define how elements in different states appear in a view set to a particular phase. Each filter specifies what to do with elements in each of four states:

• New: Elements created in the view’s phase
• Existing: Elements created before the view’s phase and not yet demolished
• Demolished: Elements created before the view’s phase and demolished in the view’s phase
• Temporary: Elements created and demolished within the same phase

For each state, the filter specifies one of three display options: Show (display normally), Overridden (display with custom graphic overrides), or Not Displayed (hide entirely).

Default filters include:

• Show All: Displays all element states
• Show Complete: Shows only New and Existing; hides Demolished and Temporary
• Show Previous + Demo + New: Typically used for demolition plans
• Show New: Shows only newly created elements
• Show Previous + New: Shows retained existing elements and new work, without highlighting demolitions

Graphic Overrides

The third tab, Graphic Overrides, controls the visual style of each element state. For each of the four states, you can define:

• Projection line weight and colour
• Cut line weight and colour
• Surface pattern and colour
• Whether to use the element’s own material (the default for New and Existing) or a specific override

Standard conventions in UK practice typically show existing elements in grey (reduced contrast) and demolished elements in a red dashed line style or with a red halftone pattern. New elements appear in the standard black line style. These conventions should be set up consistently across your office standard template and applied to all project views through view templates.

Applying Phases to Elements

When you create an element in a Revit view, its Phase Created is automatically set to the phase of that view. This is the most important habit to establish: always work in a view set to the correct phase for the work you’re doing.

To mark elements for demolition, either:

• Select the element and change Phase Demolished in the Properties panel, or
• Use the Demolish tool on the Modify tab and click elements to mark them

The Demolish tool is more efficient when you’re marking many elements, but it applies the current view’s phase as the demolition phase — so ensure you’re in the correct phase view before using it.

Handling Partial Demolitions

One of the more nuanced situations in renovation work is partial demolition — where only part of an element is being removed. For example, breaking through an existing external wall to create a new opening. Revit handles this by:

1. Demolishing the original wall element (Phase Demolished = relevant phase)
2. Creating two new wall elements representing the portions that remain (Phase Created = same phase)
3. Placing the door or opening family in the gap

This approach accurately represents the construction sequence: the original wall is removed, the opening is formed, and two shorter walls remain on either side. On a demolition plan, the original wall shows as demolished; on a proposed plan, the two shortened walls show as existing (retained) and the new door shows as new.

Multi-Phase Projects: A Practical Example

Consider a hospital expansion project with four phases: Enabling Works (demolishing an existing outbuilding and diverting services), Phase 1 New Build (a new ward block), Phase 2 Refurbishment (upgrading an existing ward block), and Phase 3 Landscaping.

The Revit model would be structured as follows:

• Existing buildings modelled with Phase Created = Existing
• The outbuilding marked with Phase Demolished = Enabling Works
• New ward block created with Phase Created = Phase 1 New Build
• Partitions and finishes in the existing ward marked with Phase Demolished = Phase 2 Refurbishment
• New finishes and partitions in the refurbished ward created with Phase Created = Phase 2 Refurbishment
• Landscaping elements created with Phase Created = Phase 3 Landscaping

From this single model, you can generate floor plan drawings for each phase by creating views set to each phase with appropriate phase filters. A Phase 1 Proposed floor plan shows the completed enabling works, the new ward block fully built, and the existing ward as existing (unchanged at this stage). A Phase 2 Proposed floor plan shows the same new ward block (now existing) plus the refurbished ward as new work.

Phase-Specific Schedules

Schedules can be filtered by phase parameter, which is enormously useful for cost planning and programming:

• A wall area schedule filtered by Phase Created = Phase 1 New Build gives you all new walls being constructed in that phase
• A floor area schedule filtered by Phase Demolished = Phase 2 Refurbishment gives you the extent of floor finishes being stripped in that phase
• A room schedule filtered by phase creates a room data sheet that reflects only the rooms relevant to each phase package

This phase-filtered schedule data can be used to populate a cost plan template — matching the phased breakdown of the construction programme — directly from the model, without manual data entry.

Communicating Phasing to Stakeholders

One of the most effective ways to communicate a complex phasing programme to clients and planning authorities is through a series of phased floor plan drawings, each showing the cumulative state of the building at the end of each phase. Revit makes this straightforward: create a floor plan view for each phase, apply the Show Complete filter, and place them on a single sheet in sequence. The result is an intuitive visual narrative of how the project will develop over time.

For construction teams, demolition drawings are often more important than proposed drawings in the early stages of a project. A well-configured demolition plan — showing what’s retained, what’s demolished, and what’s new — prevents misunderstandings on site and reduces the risk of accidental demolition of structural elements. The standard UK convention of red for demolition and black for new work is immediately legible to experienced contractors.

Common Phasing Mistakes

• Creating elements in the wrong phase view: If you model a new wall while in an Existing phase view, that wall will be assigned Phase Created = Existing and appear as an existing element in all subsequent phase views. Always check your view phase before creating elements.
• Not using phase filters consistently: If different views use different phase filters without a clear rationale, the drawings become confusing. Define view templates that lock phase filter assignments for each drawing type.
• Overcomplicated phase structures: More phases mean more complexity. If a project genuinely has multiple construction phases, structure them carefully. But resist the temptation to add phases for every minor scope change — two phases (Existing and New Construction) are sufficient for most refurbishment projects.
• Forgetting to set Phase Demolished for Temporary elements: Temporary construction elements (scaffolding, temporary propping, construction hoarding) should have both Phase Created and Phase Demolished set, so they only appear in the relevant phase views.

Integrating Phasing with the Programme

Revit’s phase structure doesn’t directly link to a construction programme — it doesn’t know that Phase 1 runs from January to June, for example. However, the phase naming convention can be used to align with programme milestones, and the phase-filtered schedules can be exported and matched against the master programme in a separate planning tool such as Microsoft Project or Asta Powerproject.

More sophisticated 4D BIM workflows link Revit elements directly to programme tasks using tools like Navisworks TimeLiner or specialised 4D simulation software. These tools can animate the construction sequence, showing elements appearing and disappearing according to their programmed installation dates — a powerful visualisation tool for complex sequencing problems.

If you need access to Navisworks alongside Revit for 4D coordination, the Autodesk AEC Collection at £149.99 includes both applications in a single package.

Start working with Revit’s phasing tools today — Autodesk Revit is available from GetRenewedTech for £39.99.

Phase Filters in Detail

Phase filters control the graphic appearance of elements in each phase state on a per-view basis. They are configured in the Phasing dialogue under Manage, and each filter specifies how elements in each phase state appear:

• New: How elements created in the current phase appear (typically solid lines, normal weight)
• Existing: How elements that existed before the current phase appear (typically shown with a half-tone or specific line weight)
• Demolished: How elements being demolished in the current phase appear (typically a dashed line pattern with a specific override colour)
• Temporary: How elements that exist in the current phase but will be demolished in a future phase appear

Revit ships with several pre-configured phase filters. The Show All filter displays all phases simultaneously, which is useful for internal coordination reviews. The Show Previous + New filter shows only the elements that existed before the current phase and the new elements being added — the standard setup for a “proposed works” drawing. The Show Demolition filter is used specifically for demolition drawings.

Using Phasing for RIBA Stages

On large refurbishment or phased new construction projects, Revit’s phasing model can be aligned with RIBA work stages. Rather than just “Existing” and “New Construction”, you might define phases for each RIBA stage deliverable — RIBA 2 concept proposals, RIBA 3 developed design, RIBA 4 technical design — with each stage building on the previous. This is admittedly an advanced use of phasing, but for projects that involve significant design development and change over time, it provides a structured way to understand what was decided at each stage and to produce retrospective documentation if needed.

Coordination with the CDM Regulations

The CDM 2015 Regulations require construction projects to maintain health and safety records throughout the project lifecycle, including information about the structure as built. A phased Revit model, if maintained correctly, provides an auditable record of which elements were demolished, which were retained, and which were added at each stage — information that feeds directly into the Health and Safety file that the principal designer is required to deliver at project completion.

Embedded parameters on retained elements (noting their age, material composition, known hazardous materials such as asbestos or lead paint) alongside the phasing information create a BIM model that genuinely supports CDM compliance rather than being purely a drawing production tool.

Summary

Revit’s phasing tools provide the infrastructure needed to manage the full complexity of construction projects where existing conditions, demolition, and new work must be tracked, documented, and communicated clearly. By assigning phases to elements, configuring phase filters for different drawing types, and using phased views to produce the right representation for each deliverable, you can produce a complete suite of project drawings from a single coordinated model — eliminating the duplication and inconsistency that comes from maintaining separate existing and proposed drawing sets.

Whether you’re working on a straightforward extension or a complex multi-phase urban regeneration project, Revit’s phasing tools scale to the task. Autodesk Revit is available from GetRenewedTech at £39.99. For teams working across architecture, structure, and infrastructure, the Autodesk AEC Collection at £149.99 offers the complete AEC toolset.