Insolation Hill

Insolation Hill builds an insolation-hill volume in Revit from a selected site boundary and the BIMO_InsolationTarget instances placed in the project. The command creates an initial site volume, builds one restrictive solar volume for each target, subtracts those volumes, and writes the result as a DirectShape in the Mass category.

Current availability: the command is registered in the BIMO Library under BIMO > Analyze, supports Autodesk Revit 2023 and later, and requires an active paid BIMO license. It is hidden in the default Ribbon scheme and can be enabled through Workspace Ribbon configuration.

When To Use It

Use Insolation Hill when you need to:

• build a volumetric development constraint from defined insolation targets;

• compare several hill variants in one Revit project;

• test different solar time ranges for individual target points;

• create Revit geometry that can be visually compared with masses and proposed building volumes.

The result depends on the selected methodology, solar profile, project True North, and placement of BIMO_InsolationTarget instances. Validate these inputs before using the result for design or regulatory decisions.

Requirements Before Running

• Open a Revit project. Family documents are not supported.

• Use Revit 2023 or later.

• Prepare at least three straight Revit line elements forming one closed site boundary.

• Load and place at least one BIMO_InsolationTarget family instance in the project.

• Check the active Daylight Measurement profile: latitude, day of year, sunrise, and sunset.

• Check True North for the active Project Location.

• If you want a specific hill material, make sure that material already exists in the project.

The command does not create or load BIMO_InsolationTarget automatically. It uses every instance of that family found in the active document.

Site Boundary

The fastest and most convenient workflow is to select all straight lines of the closed site boundary in Revit first, then run Insolation Hill. If compatible straight lines are already in the current selection, BIMO uses them directly and skips the additional manual selection prompt.

If no compatible boundary lines are preselected, Revit asks you to select them after the command starts. Only straight CurveElement objects whose geometry is a Line are supported.

Use at least three lines forming one closed loop. If the boundary is not closed or contains unsupported elements, the command cancels without creating a partial result.

Insolation Targets

The hill uses all BIMO_InsolationTarget family instances in the active project. BIMO creates one restrictive solar volume for each target and subtracts those volumes from the initial site volume.

By default, every target uses sunrise and sunset from the active Daylight Measurement profile.

A target can override only its solar time range through instance parameters:

When the override is enabled, both values must be in the range 1-23, and Sunset Hour must be greater than Sunrise Hour. If the values are missing or invalid, BIMO identifies the problematic target and cancels the command.

Unlike Solar Exposure, Insolation Hill includes the Sunset Hour itself when generating the solar directions.

Solar Settings

Insolation Hill uses the active Daylight Measurement profile for:

• latitude;

• day of year;

• default sunrise and sunset hours;

• project True North orientation.

The hill uses a fixed solar step of 60 minutes. The Solar Exposure Minute Step setting does not affect the hill calculation.

A verified profile uses its fixed catalog values. With Custom, the manual profile values are used.

Insolation Hill Settings

Output Geometry

Auto tries these modes in order:

1. BRep - exact Revit BRep geometry;

2. TessellatedSolid - a closed triangulated Solid;

3. Mesh - tessellated mesh geometry.

You can select any mode explicitly. In an explicit mode there is no fallback to another output type: if conversion fails, the command cancels and suggests using Auto, another mode, or adjusted input geometry.

Hill Material

When Hill Material Name is filled in, BIMO searches the active project for a material with that name and passes its ElementId to the BRep, TessellatedSolid, or Mesh output path.

If the material cannot be found, the command cancels before creating the DirectShape. Leave the field empty when no specific material is required.

Step-By-Step

1. Place the required BIMO_InsolationTarget instances in the project.

2. Check the active Daylight Measurement profile and project True North.

3. If needed, set target-specific Sunrise Hour / Sunset Hour values and enable BIMO Override Solar Time Range on those targets.

4. Prepare a closed site boundary from straight Revit lines.

5. Preselect all boundary lines in Revit. This is the recommended and fastest workflow.

6. Run Insolation Hill.

7. Check Hill Height, Hill Material Name, and Output Geometry in the command settings.

8. If the boundary was not preselected, select the site-boundary lines in the Revit prompt and finish the selection.

9. Inspect the new Mass-category DirectShape in the model.

What Is Created In Revit

Every successful run creates a new DirectShape in the Mass category.

The command does not search for, replace, or update an existing Insolation Hill. This allows several calculation variants to remain in the same project for comparison and manual cleanup.

If you later move targets, change the boundary, or modify settings, the existing DirectShape does not rebuild automatically. Run the command again to generate a new variant.

Common Problems

No BIMO_InsolationTarget family instances were found

The active project contains no BIMO_InsolationTarget instances. Load the family, place one or more targets, and run the command again.

Site boundary does not form a closed loop

Make sure at least three straight lines are selected and that they form one closed loop without gaps.

Invalid solar time range override

A target has BIMO Override Solar Time Range enabled, but Sunrise Hour / Sunset Hour are missing or invalid. Correct the values or disable the override for that target.

Material was not found

Hill Material Name does not match a material in the active project. Correct the name or leave the field empty.

Output geometry could not be created

If you selected BRep, TessellatedSolid, or Mesh explicitly, try Auto. If the problem remains, review the site boundary and target placement: complex Boolean results can produce geometry that a selected Revit conversion path cannot represent.

Current Limitations

• Revit 2023 and later only;

• the site boundary must use straight Revit lines;

• all BIMO_InsolationTarget instances in the active project are used; selecting only a subset at runtime is not supported;

• solar-direction sampling is fixed at 60 minutes;

• existing hills do not update automatically;

• the BIMO_InsolationTarget family must already be loaded into the project.