> ## Documentation Index
> Fetch the complete documentation index at: https://docs.arterial.design/llms.txt
> Use this file to discover all available pages before exploring further.
# Massing
> 3D Visualizations of Arterial's information
Massing Simulations help visualize the policies and datasets that Arterial has access to—and allows you to derive insights about your project's potential!
A massing on Arterial is composed of two key components:
* **Typology**: a set of storeys and design elements that define the building's envelope
* **Layout**: the types of units and floor plate-level arrangements within the building
Based on these elements, Arterial can provide insights into:
* **Floor Plate Designs**: rectangular or irregular floor plates with your selected units, optimized for revenue
* **Entitlements**: the probability of a project being approved & potential development precedents
* **Design Details**: basic GFA/GLA information, estimated amenity spaces, and other design elements
* **Finances**: unit rents/sales information, NOI/estimated cap rate, returns, valuation, etc.
* **Construction Costing**: the estimated cost of construction based on Arterial's material modelling
## Quickstart
All massing simulations are tied to a project, and can be created by navigating to the **Massing** tab in the sidebar.
When you click **New Massing**, you'll be prompted to select your massing's setback lines; these are the lines that inform the building's envelope.
You can select the *type* of setback using **Select**; click on the greyed out lines on the map to the left to select them.
These lines will be autofilled based on the other massings in your project;
click **Reset** to change the lines.
Once all lines are selected, the building envelope will be generated in gray on the map.
Arterial has a large selection of pre-defined, customizable massing templates that can be used to speed up your ideation; use the **Select Development Typology** dropdown to choose one.
You can start from scratch by using one of the **General Templates**,
highlighted at the top. To add in massing details, skip to the [design
documentation](#massing-design)
Once you've selected both, hit **Continue** to create the massing.
Most templates come with pre-defined amenity spaces for internal layout simulation; you'll need to select the unit types that you'd like to use in the **Layout** tab.
## Massing Design
### Core Constructs
Massing typologies are split into two key parts: storey design and window wells. Each storey has a set of levers attached to it—height and stepbacks. Stepbacks aggregate across floor plates, just as they would in architecture.
You can add window wells afterwards in the **Typology** tab. These are defined by three parameters:
* **Length**: the horizontal extent of the window well
* **Side depth**: how deep the window well extends into the building
* **Offset**: the positioning of the window well along the building face
When changing any massing, Arterial will give you the option to save the project to a new copy or the same one. This lets you quickly revert and compare changes between different design iterations.
### Generative Typologies
Rather than needing to create typologies from scratch, you can also get Arterial to generate certain compliant versions for you by pressing on **Generate**. When prompting, you have two options:
* **Full Generation**: Generate a complete typology by pressing **Generate** after adding your prompt
* **Augmentation**: Make additions to existing typology by pressing **Augment**
This AI-powered approach allows you to quickly explore design variations while maintaining compliance with local regulations and best practices.
### Highest-and-Best-Use
Arterial can take all the policies, precedents, and planning information in the area to come up with its own version of a highest-and-best-use study. This analysis will take slightly longer than other generative forms, but it will produce the envelope that rests inside the maximum extent of the law.
This feature leverages Arterial's comprehensive understanding of local zoning regulations, building codes, and development precedents to automatically generate the most economically viable building envelope for your site.
## Templates & Simulations
### Pre-Defined
Templates are pre-defined massing simulations that come with typologies and layouts. You can add them using the dropdown at the top of the massing sidebar or during setup; all templates are pre-vetted for quality and compliance.
Certain templates—the "Optimal" ones—are intelligent and exist as versions of highest-and-best-use massing based on specific building forms. These templates automatically incorporate local regulations and market conditions to suggest the most viable development approach.
### Custom
To save your own typology as a template for future use, you can click on the template dropdown and add a name. This allows you to build a library of custom typologies that work well for your specific market conditions or design preferences.
Custom templates maintain all the same functionality as pre-defined templates, including the ability to generate layouts, analyze finances, and export information for further development.
## Next Steps
Set up floor plate arrangements and unit mixes for your massing
Assess the economic and financial viability of your massing design
Simulate planning risks and development precedents for your massing
Export your massing, analyses and datasets in a variety of formats