ub.Elevations is an Autodesk Revit add-in from underbim, a Portugal-based BIM consultancy that has worked in BIM, Revit training, consulting, and software development since 2001. It is one of eight independent add-ins in ub.Suite Edition 1, which launched in late October 2026. Despite its name, it doesn't create elevation views. It's a vertical data tool. Its tagline, "Know where every element starts and ends," sums up the approach. It calculates each element's upper and lower elevations from its extents in the Revit model and writes them to usable instance parameters, using either Project or Survey coordinates as the reference.
Note on sources: This summary is based mainly on underbim's full Elevations product page, which covers the workflow, feature explorer, coordinate references, parameter output, and licensing. Background on Revit's elevation parameters and coordinate system comes from Autodesk documentation and community forums. An independent review or hands-on test wasn't found.
The Problem Area: Vertical Data in Revit
Knowing the absolute top and bottom elevation of elements matters for coordination, clearance checks, scheduling, tagging, and handing data to contractors or other software. Revit shows this information graphically, but it isn't consistently available as data that can be scheduled. Autodesk documentation and user forums describe several gaps:
- Built-in elevation parameters only exist for some categories: Ducts, pipes, cable trays, and conduit have detailed top, bottom, and centerline elevation parameters, and structural framing has Elevation at Top and Elevation at Bottom. Many other categories have no equivalent absolute elevation values.
- Level-relative values, not absolute ones: Parameters such as Elevation from Level give an offset from a level, not an absolute height. They're also unavailable in multi-category schedules.
- No level elevation in schedules: For elements such as columns, a schedule can show the base and top level names and offsets, but not the level's elevation as a number. That means you can't calculate the actual top or bottom elevation in a schedule or tag. This is a long-standing request on the Revit Ideas board.
- Annotation isn't data: Spot elevations can show heights relative to the Project Base Point or the Survey Point, but they're annotations in a view, not parameter values you can filter, schedule, or export.
- Dynamo workarounds go stale: A common fix is to add shared parameters and fill them with a Dynamo script. Forum users point out that values become outdated as heights and offsets change, unless someone remembers to rerun the script.
- Coordinate references cause confusion: Revit has an Internal Origin, a Project Base Point (the project's local zero), and a Survey Point (the real-world reference, often sea level). The same element can have very different elevation values depending on which reference is used.
Elevations addresses this gap. It works the same way across whichever categories you choose: it calculates top and bottom values and writes them to parameters you control, with the coordinate reference stated explicitly.
Key Facts
- Purpose: Calculate each element's top and bottom elevations and write them to instance parameters.
- Product family: One of eight independent add-ins in ub.Suite Edition 1.
- Reference: Project or Survey coordinates.
- Data source: Entire Project, Current View, or Selection.
- Calculation: Based on the extents of each element's bounding box, for fast, consistent results.
- Output: Separate instance Length parameters for Top and Bottom. If no suitable parameter exists, the tool can create and bind a shared parameter.
- Reversibility: Both preparing parameters and writing values are committed through Revit transactions and can be undone.
- Licensing: Perpetual license by Edition. Updates within the Edition are included, and major Edition upgrades are optional. Single-activation and two-activation options are offered.
- Documentation: The product page links to setup and documentation. underbim also has a Downloads area, a Customer Portal, and a public GitHub repository for signed releases and update manifests.
The Product Idea
The tool is built on one idea: turn each element's vertical extent into usable project data. You select the model categories, choose the Top and Bottom target parameters, and pick the elevation reference. The add-in then prepares the parameters and writes the values consistently. The process moves through four stages: Model (selected categories), Target (Top and Bottom parameters), Reference (Project or Survey), and Result (usable elevation values).
Workflow: Set the Reference, Write the Result
- Categories: Select the model categories that should receive elevation data.
- Targets: Choose or define compatible instance Length parameters for Top and Bottom.
- Reference: Choose Project or Survey elevation coordinates.
- Source: Process the Entire Project, the Current View, or the current Selection.
- Calculate: Work out Top and Bottom from each element's bounding box.
- Write: Prepare the parameters and write the values. The operation can be undone.
Model Categories and Data Source
The operation is limited to the categories you select, not the whole project as one undifferentiated set. The category list can be filtered to show only used categories (those actually in the model), which helps on large projects. The active category selection also determines which categories the parameters are bound to and which elements are processed, so values are written only to the chosen set. Within those categories, the data source sets which elements are processed:
- Entire Project: Processes all matching element instances (not types) across the document.
- Current View: Limits processing to elements available in the active Revit view.
- Selection: Uses the current selection, or the Select Elements option, to set exactly which elements are processed.
Reference and Targets
underbim stresses that Project and Survey aren't just display options. They set the coordinate reference used for the values written to the model:
- Top: A compatible instance Length parameter that receives the element's upper elevation.
- Bottom: A separate compatible instance Length parameter that receives the lower elevation.
- Project: Writes elevations in the project's coordinate system, measured from the Project Base Point.
- Survey: Converts the measured height (Z value) using the active Project Location, giving elevations relative to the survey reference.
Example from the product page: An element reads Top 12.40 and Bottom 0.00 in Project coordinates. With the Survey reference, the same zero point reads +48.20.
Parameter Output
Setting up the parameters is part of the same operation. The tool can use existing compatible parameters, or it can create missing definitions and bind them to the selected categories:
- Top and Bottom: Separate instance Length parameters receive the top and bottom of each element's bounding box.
- Shared parameter when needed: If no usable target exists, the tool creates and binds a shared Length parameter.
- Usable afterward: Because the values are stored as ordinary instance parameters, they can be used in schedules, tags, view filters, and exports like any other parameter data.
- Undo: Preparing the parameters and writing the values are both committed through Revit transactions and can be undone.
A note on bounding boxes: A bounding box gives an element's overall vertical extent, meaning its highest and lowest points. For sloped or irregular elements such as sloped beams, ramps, or roofs, Top and Bottom are those extremes, not the elevation at a particular point along the element. Revit bounding boxes are also aligned to the model's axes, which doesn't affect vertical values but is worth knowing when reviewing the results.
Place Within ub.Suite 1
ub.Suite 1 includes FilterToSchedule, ModelData, InterferenceInvestigator, ProjectManager, ConstraintScanner, ScopeViews, Elevations, and BackupMover. The launch announcement grouped Elevations with the "views" tools, but the product page shows it's really a model data tool. It fits best alongside these:
- ModelData and FilterToSchedule: These are the suite's model data and schedule tools. Elevations creates new parameter data (Top and Bottom), which these tools could then review, filter, or schedule. underbim hasn't described a direct integration.
- InterferenceInvestigator: Absolute top and bottom values are useful for checking vertical clearances and conflicts. That makes Elevations a natural partner for coordination work, though no link between the two is described.
- ScopeViews: Despite the similar "views" grouping, ScopeViews creates plan, section, and 3D views from Scope Boxes, while Elevations creates no views at all.
Elevations follows the suite's shared design approach. Choices are made up front in one place instead of across a long series of dialogs, the scope is set deliberately, and every change to the model can be undone.
Compared with Native Revit Tools
Open Questions
- Are values updated automatically when elements move or levels change, or does the tool need to be rerun?
- How are nested families, element groups, and elements with symbolic or invisible geometry handled in the bounding box calculation?
- Are there default names for the shared parameters it creates?
- Is there a result report, like ScopeViews' Status area, listing skipped or failed elements?
Bottom Line
Elevations fills a long-standing Revit data gap. It gives elements in any selected category absolute top and bottom elevations as real instance parameters, referenced to Project or Survey coordinates. You choose the categories, target parameters, reference, and scope up front, and the tool can create and bind shared parameters when needed. Every change can be undone. For BIM coordinators who need vertical data for clearance checks, coordination, schedules, tags, or contractor handover, it replaces fragile Dynamo workarounds with one controlled operation. Keep in mind that values come from bounding boxes and may need to be refreshed after design changes.
Sources
- ub.Elevations product page
- ub.Suite 1 overview
- ub.Suite 1 launch announcement
- underbim signed releases repository
- Autodesk Help: Elevation Properties for MEP Elements
- Autodesk Support: Structural framing Elevation at Top/Bottom
- Autodesk Community: Scheduling Elevation from Level
- Revit Ideas: Column top and bottom level as length value
- Autodesk Help: Project Base Point and Survey Point
- BIM Pure: Revit Base Points and Coordinate System
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