7 min read Updated May 2026

Thumb Gen Documentation

Complete guide to installing, configuring, and using Thumb Gen to standardise every Revit family thumbnail in your library.

Quick Start

Five steps to refresh your first family thumbnail.

Installation

Single installer for every Revit version

One installer - AUTOM8LABS_ThumbGen_v1.0.0.exe - covers Revit 2022, 2023, 2024, 2025, 2026, and 2027 in a single pass. The wizard detects every Revit version installed on the machine and drops the matching binaries into each version folder. No per-version downloads, no manual targeting.

Install paths

Thumb Gen follows Autodesk's standard ApplicationPlugins layout:

• Revit 2022-2026 → C:\ProgramData\Autodesk\ApplicationPlugins\AUTOM8LABS.ThumbGen.bundle\
• Revit 2027 → C:\Program Files\Autodesk\ApplicationPlugins\AUTOM8LABS.ThumbGen.bundle\ (per Autodesk's 2027 packaging rules)

Each Contents\{year}\ subfolder holds the Revit-version-specific DLL. The add-in manifest is bundled in PackageContents.xml so Revit auto-discovers it on next launch.

Accessing the tool

After installation, launch Revit and open or create a family document (.rfa). Find the button at:

Add-Ins tab → AUTOM8LABS panel → Thumb Gen

The AUTOM8LABS panel is shared with other AUTOM8LABS tools. The Thumb Gen button is enabled only when the active document is a family - it is disabled for project documents.

Supported Revit Versions

Revit Version	Framework	Status
Revit 2022	.NET Framework 4.8	Supported
Revit 2023	.NET Framework 4.8	Supported
Revit 2024	.NET Framework 4.8	Supported
Revit 2025	.NET 8.0 (Windows)	Supported
Revit 2026	.NET 8.0 (Windows)	Supported
Revit 2027	.NET 10 (Windows)	Supported

Home Tab

The Home tab - Generate Family Thumbnails - is where you configure how every family in your library should look. It exposes two grids - a Default Appearance grid and a Default Appearance Override grid.

Default Appearance grid

Two rows that always exist - 3D Default and 2D Default. Every family that doesn't match an override row uses these.

• 3D Default - applies to every 3D-categorised family (Casework, Columns, Doors, Furniture, Mechanical Equipment, Plumbing Fixtures, Lighting Fixtures, Generic Models, etc.)
• 2D Default - applies to every 2D-categorised family (Detail Components, Generic Annotations, Title Blocks)

Each row exposes four cells - VIEW, VISUAL STYLE, DETAIL, SCALE:

Cell	3D row options	2D row options
VIEW	Top, Front, Right · Top, Front, Left · Top, Back, Right · Top, Back, Left	Floor Plan (only valid option for 2D family editors)
VISUAL STYLE	Wireframe · Hidden Line · Shaded · Shaded with Edges · Consistent Colors · Realistic · Realistic with Edges · Ray Trace	Same set
DETAIL	Coarse · Medium · Fine	Same set
SCALE	35 scale denominators - Metric (1:1 to 1:5000) followed by Imperial (12"=1'-0" to 1"=100'-0")	Same set

The View dropdown is context-aware per row - 2D rows never offer 3D isometric options because a 2D family editor has no isometric or elevation view to render.

Default Appearance Override grid

Per-category overrides. Each row targets a list of Revit categories - whenever a family belonging to one of those categories is processed, the override's View / Visual Style / Detail / Scale wins over the matching default row.

• Click the + button to add a row
• Click the CATEGORIES cell to open the category picker
• The row's View dropdown automatically reclassifies based on what you pick - all selected categories classify as 2D → row flips to 2D mode (Floor Plan only); any 3D, Truss, Rebar, or unrecognised category → row stays in 3D mode (four isometric options)
• The − button removes the selected row

Settings Tab

The Settings tab holds five cards - Appearance, Hide Elements, Output, View Name, and Shared Settings. Every option persists to disk on change.

Appearance

• Enable gradient backgrounds - applies a gradient sky background to 3D views
• Enable 'Preview Visibility' option - toggles Revit's preview-family-visibility flag on the generated view, so geometry hidden in the family is still rendered in the preview
• Smooth lines with anti-aliasing - enables View3D.SmoothEdges on isometric thumbnails

Hide Elements

Thirteen visibility toggles. Each one hides the corresponding category in the generated thumbnail view only - the family geometry itself is never modified.

Left column	Right column
Hide dimensions	Hide flip controls
Hide reference planes	Hide room calculation points
Hide reference lines	Hide host elements
Hide reference points	Hide connector elements
Hide text notes	Hide void elements
Hide invisible lines	Hide light sources
	Hide imported elements (.dwg, etc.)

Output

• Export thumbnail as PNG next to the family file - writes <FamilyName> - <View>.png alongside the .rfa
• Use square aspect ratio for exported PNG - post-processes the export onto a square white canvas at the configured resolution. Useful for content-library systems that expect square thumbnails
• Resolution (px) - 256 · 512 · 1024 · 2048. Long-edge pixel count drives Revit's ImageExportOptions.PixelSize and the square-canvas dimension

View Name

The name given to the dedicated thumbnail view stored inside each family document. Default: Thumbnail.

If a view with the chosen name already exists in the family and is compatible with the family's category (a View3D for 3D families, a non-3D view for 2D / annotation / truss families), Thumb Gen reuses it in place. Orientation, display style, detail level, scale, and visibility flags are all reapplied to that existing view. No _1 / _2 suffix sprawl. If the existing same-named view is the wrong type for the category, Thumb Gen deletes it (when permitted) and creates a fresh view - if delete is refused, it falls back to a suffixed name as a last resort.

Shared Settings

Point Thumb Gen at a network folder (UNC or mapped drive) holding a firm-wide thumbgen-settings.json. The first time you browse to an empty folder, your current local settings are pushed up to seed the firm file. The next user who browses to the same folder pulls the firm settings down. Every subsequent change writes to both the local cache and the shared folder.

• Local cache always wins offline - if the network share is unreachable, the on-save thumbnail refresh and dialog continue to work with the last-known settings
• Last-write-wins concurrency - suitable for small / medium AEC firms. If two users save settings within the same second, the later write replaces the earlier one

Batch Folder

Click Batch Folder in the footer to open a separate dialog that processes every .rfa file in a folder. This is a licensed feature - see the Licensing section.

Configuration

• Source - folder of family files to process. Optionally include subfolders.
• Output - overwrite the original .rfa files, or save the updated families into a separate output folder (originals untouched).
• Log - per-file status (success / skipped / failed) with the message returned by the updater.

Progress dialog

When the batch starts, a separate progress dialog pops out with a live cyan progress bar (X of N), the current file name, and three buttons:

• Pause / Resume - flips a ManualResetEventSlim gate the batch loop waits on between files. The WPF dispatcher is pumped on a 50 ms tick while paused so the buttons stay clickable. Pause and Resume take effect at the next file boundary (current file always finishes cleanly).
• Cancel - flips the CancellationToken. Like Pause, takes effect at the next file boundary.

Each family is opened in a background document, classified, processed through the full pipeline, and saved. Families saved in older Revit versions trigger an upgrade-confirmation dialog before processing - uncheck any you don't want upgraded and they will be skipped.

Family Categories

Thumb Gen classifies every family into one of five buckets and runs the matching view pipeline.

Category bucket	Examples	View pipeline
3D	Casework, Columns, Doors, Furniture, Generic Models, Lighting Fixtures, Mechanical Equipment, Parking, Planting, Plumbing Fixtures, Structural Columns, Windows, etc.	View3D.CreateIsometric
2D / Annotation	Detail Components, Generic Annotations, Title Blocks	Duplicate FloorPlan view + hide annotation categories
Truss	Structural Truss	Isometric with truss-specific display-style guard
Rebar	Rebar, Rebar Shapes, Area Reinforcement, Path Reinforcement	Reuses an existing valid preview view
Unknown / model fallback	Third-party model categories	Treated as 3D

Categories not explicitly enumerated fall through to CategoryType.Model → 3D, or CategoryType.Annotation → 2D. 14 family-category buckets are supported in total.

Licensing

Thumb Gen follows a freemium three-tier model. The title bar always shows the current state - Free Version when unlicensed, Licence valid until DD/MM/YYYY when a key with an expiry is cached, or Licence active for a key with no expiry.

Free (no licence required)

Everything an individual Revit user needs to standardise the thumbnails on the families they are actively working on:

• Apply on the active family - refresh the embedded preview in one click
• Both default appearance rows (3D + 2D) with full Visual Style / Detail Level / Scale / View choices
• Per-category overrides - unlimited override rows for Doors, Trusses, Title Blocks, etc.
• All 13 hide-element toggles (dimensions, reference planes, text notes, etc.)
• All 14 supported family-category buckets
• Local settings persistence (including default and override rows)

Individual - £49/year per machine activation

Built for solo Revit users and small studios who want library-wide automation on their own workstation. Self-serve checkout - buy 1-5 licences directly on the site, each licence activates one machine:

• Everything in Free
• Batch Folder - process every .rfa in a folder unattended, with Pause / Resume / Cancel
• PNG export alongside the .rfa for content-library systems (Output card)
• Appearance overrides - gradient backgrounds, preview-visibility toggle, smooth edges
• Standard email support

Pro - £99/year, unlimited machines

For firms with 6+ Revit users where managing individual machine activations becomes unwieldy. Required for any organisation activating on more than 5 machines.

• Everything in Individual
• Unlimited machine activations under one licence
• Firm-wide shared settings - point at a network folder, every user pulls the same thumbgen-settings.json (local cache wins offline)
• Priority support

Buy at autom8labs.io/products/thumbgen.

Frequently Asked Questions

Changelog

Troubleshooting

Thumb Gen button is greyed out

The button is enabled only when the active document is a family (.rfa). It stays disabled for project documents (.rvt). Open or create a family in the Family Editor first.

Apply doesn't seem to do anything

The family must be saved to disk before Apply can write the .rfa preview back. New families with no path are skipped silently. Save the family once (anywhere on disk), then click Apply.

Licence won't activate

Licence keys validate against api.autom8labs.io. If activation fails:

1. Check that your firewall or VPN is not blocking outbound HTTPS to api.autom8labs.io
2. Verify the licence key in the activation dialog character-for-character (keys are case-sensitive)
3. If you are moving the licence between machines, deactivate it on the old machine first - each Individual licence is one machine activation
4. Still stuck? Email info@autom8labs.io with the key and the machine name

Pause / Resume buttons unresponsive

Pause, Resume, and Cancel only take effect at the next file boundary - the current family always finishes cleanly. If you click Pause and the progress bar advances one more file before pausing, that is by design (interrupting mid-transaction would corrupt the .rfa).

Don't run alongside another preview-management add-in

Two tools that both set SaveAsOptions.PreviewViewId on family save will fight each other and produce undefined results. Disable other preview-management add-ins before running Thumb Gen.