About the Tool

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Revit Geometry Kernel Deviation Assessment helps explain why some Revit models feel slow, unstable, or difficult to work with—even when there are few or no warnings.

Autodesk Revit is designed to work most efficiently with native solid geometry that is compact, shallowly nested, and created directly inside Revit. These geometry types allow Revit to evaluate, regenerate, and reuse shapes quickly as a model changes.

Performance issues arise when geometry deviates from these assumptions. This can happen when:

  • Geometry is represented as meshes, which require Revit to process long lists of vertices and faces
  • Solids are imported from other formats (such as SAT), reducing editability and increasing processing cost
  • Families are deeply nested, adding complexity to how Revit resolves geometry and parameters

Each of these choices increases the amount of work Revit must do at runtime, especially as models scale.

This tool looks at how geometry is represented inside a Revit model and measures how closely it aligns with what Revit's geometry engine was designed to handle. It does not judge design intent, visual quality, or modeling style. Instead, it focuses on representation—how geometry is encoded, sourced, and structured—and how those choices affect Revit's runtime behavior.

By making these characteristics visible early, the assessment helps prevent performance issues from appearing later as slowdowns, crashes, or downstream coordination problems.

In short, the tool doesn't tell you what should be built. It explains how Revit actually processes what is built.

How Grading Works

Each family is evaluated using five factors that affect how efficiently Revit can process geometry during regeneration. Each factor contributes a percentage to the overall grade.

The goal is not to label assets as good or bad, but to describe how far their geometry representation departs from Revit's native geometry design and how much additional runtime effort that departure introduces.

1. Solid Edge Segments (30%)
What it measures

Solid Edge Segments counts the total number of tessellated edge segments from solid geometry. This represents how many line segments Revit must process when rendering edges.

Why it matters

During regeneration, Revit tessellates solid geometry into edges for display. More edge segments means more data to calculate, store, and render—especially when families are repeated many times in a model.

How it's graded
A: <500 segments B: 500–2,000 segments C: 2,000–5,000 segments D: 5,000–20,000 segments F: >20,000 segments

High edge counts directly correlate with regeneration time.

2. Mesh Edge Segments (30%)
What it measures

Mesh Edge Segments counts the triangle edges from mesh geometry (triangles × 3). This captures the complexity of imported or mesh-based geometry.

Why it matters

Mesh geometry is inherently more verbose than solid geometry. High mesh edge counts indicate complex imported geometry that Revit must process on every regeneration.

How it's graded
A: <1,000 segments B: 1,000–5,000 segments C: 5,000–10,000 segments D: 10,000–50,000 segments F: >50,000 segments

Families with zero mesh geometry receive an A grade for this criterion.

3. Face Count (20%)
What it measures

Face Count is the total number of individual surfaces that make up a family's geometry.

Why it matters

Every face must be read, tracked, and updated by Revit. As face counts increase, Revit has more work to do during regeneration—especially when families are repeated many times in a model.

How it's graded
A: <100 faces B: 100–500 faces C: 500–1,000 faces D: 1,000–5,000 faces F: >5,000 faces

Very high face counts increase processing cost and are graded lower as a result.

4. Geometry Type (10%)
What it measures

Geometry Type looks at whether a family is built from solids, meshes, or a mix of both.

Why it matters

Revit is optimized for solid geometry, which is compact and efficient to process. Mesh geometry is more verbose and requires Revit to handle much larger sets of data.

How it's graded
A: 100% solid C: Mixed solids/meshes D: Mesh-only F: No geometry

For example, a family containing 4 solids and 0 meshes scores higher than one built entirely from meshes.

5. Import Source (10%)
What it measures

Import Source identifies whether geometry was created natively in Revit or imported from another format.

Why it matters

Native Revit geometry is easier to regenerate, edit, and maintain. Imported solids and mesh-based geometry often carry additional complexity that Revit must resolve at runtime, and they are typically harder to modify or simplify.

How it's graded
A: Native Revit B: Native + some SAT C: SAT-only D/F: Mesh imports

Lower grades reflect increased runtime cost and reduced flexibility.

Nesting (Informational Only)
What it shows

Nesting indicates whether a family contains nested family instances (sub-components). Displayed as Depth and Sub-Families count.

Why it's informational

Nesting itself has minimal impact on the Revit geometry kernel. What matters is the geometry type of the nested families. A nested family with clean native solids performs well; a nested family with imported meshes does not.

How it's displayed
Nested — Shown when family contains nested instances

Nesting is flagged for awareness but does not affect the overall grade.

What This Means for Your Model

Each grade reflects how closely an asset aligns with the way Revit's geometry engine was designed to work.

Higher grades indicate geometry that stays within Revit's native assumptions: compact solids and native construction.

Lower grades indicate geometry that relies on more verbose representations, imported solids, or mesh-heavy definitions—choices that push Revit further from its optimal execution model.

As deviation increases, Revit must spend more time interpreting, regenerating, and managing geometry, and those costs compound across large models.

The grade is not a judgment of design quality; it is a measure of how far an asset's representation departs from Revit's geometry kernel design and how much additional runtime effort that departure introduces.