> For the complete documentation index, see [llms.txt](https://docs.strata.hendersonengineers.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.strata.hendersonengineers.com/workflows/mechanical-planning/zones.md).

# Zones

Group spaces into mechanical zones and manage zone details.

A zone is a group of spaces served by a common terminal unit. In a VAV system, each zone typically corresponds to a VAV box or fan-powered box.

> 📸 **Screenshot — Zones in the Layers tree** The left Layers tree with a couple of zones expanded to show their spaces, each zone in its own color, and the **Group Into Zone** / **Ungroup** row actions visible.

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## Creating a zone

**In Data view:** Press `Z` to add a new zone row.

**From the left sidebar:** Select spaces in the left panel tree → use the group action to create a zone from selected spaces.

**From canvas selection:** Select one or more spaces on the canvas → use the **Group Into Zone** action in the right panel.

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## Zone attributes

| Field          | Options                  | Description                                                  |
| -------------- | ------------------------ | ------------------------------------------------------------ |
| Name           | Free-text                | Zone label                                                   |
| Equipment Type | VAV Box, Fan Powered Box | Terminal unit type                                           |
| Subtype        | Series, Parallel         | Applies to Fan Powered Box only                              |
| Size/Inlet     | Catalog-driven           | Size inlet configuration based on equipment type and subtype |

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## Adding spaces to a zone

In the left sidebar tree, drag spaces into a zone, or use the **Group Into Zone** action when spaces are selected on the canvas or in the data view.

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## Removing spaces from a zone

Select the zone in the left panel → use the **Ungroup** action for the space. The space returns to the unassigned state and is no longer counted in that zone's tonnage.

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## Assigning a zone to a source

Zones are assigned to sources (air-handling equipment). See [Sources and Equipment](/workflows/mechanical-planning/sources-and-equipment.md) for how to group zones into a source.

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## Deleting a zone

Select the zone → press `Delete` or use the delete action.

Deleting a zone does not delete the spaces in it. Spaces return to the unassigned state.

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## Zone color coding

Each zone is assigned a color in the canvas and data views. The color is used consistently across the canvas, the left sidebar tree, and the topology view to indicate zone membership.

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## Related

* [Spaces](/workflows/mechanical-planning/spaces.md)
* [Sources and Equipment](/workflows/mechanical-planning/sources-and-equipment.md)
* [System Hierarchy](/reference/reference/system-hierarchy.md)