Create a roof system

Before you start

 Have the project address or an image, drawing, or PDF of the site available. When using an uploaded underlay, make sure you know at least one real-world reference dimension and the north direction. 

Create the project

1. Open Virto.MAX and select Create new project.
2. Choose a starting point based on your site data:
   • Google Maps: Search for the address and position the site in the map view.
   • Image or Document: Upload a PNG, JPG, or PDF plan.
   • Whiteboard: Start from an empty canvas when no reference image is needed.
     
     
3. Enter the project details and confirm the location.
4. If using an uploaded underlay, set the scale by selecting two points with a known distance, then define the north direction.

Verification: Confirm that your site scale and orientation match reality before proceeding, as all geometry and solar yield calculations depend on these settings.

Model the building

1. Draw the building outline using the Rectangle (R) or Polygon (P) action keys in the toolbar. Type exact line lengths directly during drawing if exact dimensions are known.
2. In the side panel, select the appropriate Surface Type and enter its geometric details:

Roof Types & Input Parameters

• Flat Roof:
  • Parameters: Roof height, parapet width and height, minimum edge clearance for modules.
  • Best for: Commercial buildings, industrial warehouses, or modern flat residential roofs.
• Shed Roof:
  • Parameters: Eave and ridge height (or single height + slope angle), minimum edge clearances (eaves, ridge, sides).
  • Options: Use Rotate Ridge to adjust slope orientation.
  • Best for: Single-pitch roofs typical of modern home extensions or industrial sheds.
• Open-Gable Roof:
  • Parameters: Eave and ridge height (or height + slope angle), eave/ridge/side edge clearances.
  • Options: Use Rotate Ridge to modify slope orientation.
  • Best for: Standard dual-pitch pitched roofs.
• Hip Roof:
  • Parameters: Eave and ridge height (or height + slope angle), edge clearances, valley/hip intersection clearances.
  • Best for: Multi-sloped residential roofs with sloping sides.

     3.    Add Obstacles: Model skylights, HVAC units, vents, or keep-out zones using Rectangle,                 Circle, Polygon, or Line tools. Set obstacle height and required offset/keep-out distances.

• • Pro-tip: Enable Create similar objects to detect repetitive roof obstacles automatically. Always conduct a visual check after auto-detection.

Good to Know: You can create multiple buildings and surfaces within a single project using the object tree or side panel. For roof-parallel systems, the module plane follows the roof slope—accurate roof geometry is essential for realistic 3D views, shading, and export results.

 

Create the PV Layout

1. Navigate to Module Layout and select the roof face. Use roof cycling (W) or the Object Tree if a surface is hard to click in 3D.
2. Choose a module and mounting system configuration:
   • Filtering & Favorites: Filter the database by manufacturer, power, or type. Select the Star icon next to any component to pin it as a favorite at the top of the list.
   • Missing equipment? Learn how to Add a panel to the panel database or Add an inverter to the inverter database
   Set the system mode and parameters:
   • Preset Mode: Choose pre-configured commercial mounting systems.
   • Manual Mode: Define custom parameters including setup, orientation, tilt, pitch, and exact azimuth alignment (aligned to compass or snapping to roof edges).
3. Place panels:
   • Autofill: Automatically populates all usable areas within edge and obstacle keep-out zones.
   • Free Size: Click and drag to manually define a custom layout boundary.
4. Review and refine:
   • Select individual modules, fields, or the full layout using selection shortcuts. Move, duplicate (E), or delete (Delete) modules as needed.
5. Adjust Thermal Breaks: Thermal breaks split large arrays into separate module fields to manage roof loads, preserve maintenance access, and improve visual balance. Review automatically generated breaks, remove inconvenient gaps, and re-apply them where needed. For a complete guide, see Adjust thermal breaks

Analyse and configure the system

1.  Shadow Simulation: Enable Shadow simulation for a target date and time window. Identify shaded zones and enable Shaded panel removal to automatically clear low-performing modules. For detailed steps, refer to Simulate shadow

2. Yield Estimation: Review live project yield updates in the project bar. Configure location, PVGIS weather data, and system loss parameters under Yield Settings. For comprehensive reporting, view Simulate yield
3. Inverter Configuration: Open Inverters to generate automatic stringing proposals based on panel groups, target DC/AC ratios (0.5–2.0), and voltage limits (-10°C to 70°C). Draw rectangular or polygon inverter placement zones on site. Read Configure and place inverters for full setup instructions.
4. Battery Storage (BESS): Open the battery-sizing workflow to optimize for Self-consumption or Peak load shaving. Set grid export/import limits and upload interval consumption data (.csv/.xlsx). Place battery enclosure zones directly on the drawing. See Size and place a battery - BESS
5. Consumption & Financial Modeling:
   • Upload site load profiles to calculate self-consumption and grid dependency. See Evaluate production and consumption.
   • Enter CAPEX, OPEX, utility tariffs, and discount rates to generate financial metrics (NPV, IRR, Payback, LCOE). See Create a financial model

 

Finish the Project

1.  Review Overview: Open Project & component overview in the results step to verify total module count, installed DC capacity, total system weight, and component breakdowns per roof face. 

2. Generate Report & Share:

   • Click Export > PDF report to build a customized proposal complete with company logos, brand colors, and key project views.
   • Select Publish to create a secure, web-based interactive 3D link with configurable expiration dates for client presentation. See Publish and share a project and Create a report
3.  Export to Engineering: Choose Export to download .DWG files for CAD layout work or .PVC files for advanced bankable simulation. See Export to Virto.CAD and PVsyst.