This article is relevant for users of the guided design experience only.  You may enable this in your user preferences, with the toggle labeled "Use guided design experience".

After completing  Create a New Project (Step 1), the next step for most projects is to prepare a drawing of the roof.  The roof design feature allows users to model the site, comprising a 3D roof model, neighboring homes, obstructions and trees.  An accurate site model is critical for determining how many solar panels can fit on various parts of the roof, as well as the energy that panels would produce at each location, accounting for the orientation and pitch of each roof facet, and shading from nearby objects.

Note: For projects where all panels will be mounted on the ground and not shaded by any nearby roof structure, users may skip roof design and proceed immediately to solar design.  For more information, see Create a Ground Mount Design. 

Feature details

All roof designs in Solargraf begin by creating a 2D outline of the roof using one of two methods.

1. Roof detection, which uses computer vision to analyze the property image and “detect” the perimeter of the roof, as well as all internal roof edges.
2. Manually tracing the roof’s perimeter, then dividing its facets using the Pen tool.

It is generally recommended to detect the roof, rather than tracing it by hand.  The roof detection accuracy depends on the quality of the aerial image used in the design.  Foor project at rural locations where high-definition imagery is unavailable, users may prefer to trace the roof manually, rather than detect it and then correct the outline.

Once the roof is detected, use the Pen tool to trace any missed edges.  Always start and end at an existing roof edge or corner.  Use the Select tool to select any incorrectly detected edges and then the Delete button to delete them.

If tracing the roof manually; first trace the perimeter of the roof, as seen in the image below:

Once all corners at the perimeter have been defined, select the first corner to “close” the perimeter.  Next – starting and ending at existing roof edges or corners – divide the facets of the roof by tracing over the internal edges, as seen in the image below:

Once the roof’s outline is fully traced in 2D, render the outline in 3D.  This leverages lidar data to determine the pitch of each roof facet (its angle with the ground), its azimuth (the direction it faces, relative to north), any internal walls that separate roof stories, and also detects obstructions on the roof (pipe vents, chimneys, etc) and surrounding trees.

It is important to verify the accuracy of the site model.  To do so, users may open the split screen tool, which shows the 3D model beside 3D imagery of the property (courtesy of Google Maps, pending data availability).

Users may also visualize the lidar data used in the calculations.  This can help to verify that the roof model’s height, as well as the pitch of the roof – is correct.

If the model looks correct, the user may proceed to solar design.  If the model looks incorrect, the user should opt to fix it.

When fixing the site model, the user will first be prompted to verify azimuth.  Each roof facet has an azimuth – which is a value in degrees, where south is 180 degrees.  The azimuth will always be equal to an edge belonging to that facet, or the inverse of one of its edges.  The edge that is currently identified as the facet’s azimuth is highlighted in yellow or brown.  To correct an azimuth, the user must select the roof facet using the Select tool, then select the “rotate azimuth” button until the correct edge displays in yellow (or brown).

Once all azimuths are corrected, the user may proceed to verify walls.  A “wall” in Solargraf is defined as a roof edge that has roof material on either side – thus not a part of the roof’s perimeter – and where a vertical wall appears between the two facets on either side.  Walls typically separate roof stories but can also appear at the sides of dormers.  A wall is identified in purple (or brown, where the edge is both a wall and an azimuth).  The user may select the Wall tool, and then select any edge to identify or unidentify it as a wall.

Once all walls are corrected, the user may proceed to verify obstructions and trees. The Select tool can be used to select an existing obstruction or tree and edit its properties.  The obstruction and tree tools are used to add new objects of each type.

Once all obstructions and trees are corrected, the user may re-render the 3D model.  The new 3D model will comprise all of the user’s corrections.  If needed, the user should fix the site model again, repeating these steps until the roof model looks correct (using the split screen and lidar to verify each version of the model).

Once the user is satisfied that the site model is correct, they may proceed to solar design.