Roofy.

Model from plan (DXF or DWG)

For a new build without a drone flight, Roofy generates a flat-roof model from the DXF or DWG floor plan. You choose the outline, building parts and roof structures directly in the plan, enter heights and the north direction and generate the model. This guide walks through the steps of the wizard, through the ways of adding further roof structures and through the model parameters. Measuring and the solar module layout then work as in a drone session and have their own chapters.

After generating, you measure and lay out as in a drone session: the 2D view shows the plan as background, the 3D model shows the building parts with parapet and roof structures. For tools and keyboard shortcuts see Measuring the roof guide.

Choose the file

The entry point is the “New measurement” button in the project. There you choose “From plan (DXF or DWG)” as the source instead of drone images.

  1. Start a new measurement: open “New measurement” in the project and choose “From plan (DXF or DWG)” as the source.
  2. Choose a DXF or DWG file: a floor plan of up to 25 MB. Roofy converts DWG to DXF automatically; if anything goes wrong, save the plan as DXF in your CAD software.
  3. Let Roofy read the plan: Roofy looks for closed contours, also from individual line segments, and shows the plan with every selectable contour. Drawing frames on frame layers appear grey and cannot be selected.

Choose outline and parts

No contour is preselected. You click the outline yourself; each building part gets its own height later.

  1. Click the outline: one click selects the smallest contour under the pointer, another click at the same spot the next larger one. This also reaches contours that lie inside others. When you point at the plan, exactly the contour that a click would select lights up, even if it is already selected. The plan view adapts to the height of the window. “Full screen” above the plan shows it across the whole screen; Escape first ends a running click chain and then full screen.
  2. Further building parts: in “Building part” mode, click every contour that is a separate part with its own height, for example hall and office wing. The model gets steps, and each part becomes its own roof surface. If a contour lies completely inside another part (for example a taller structure in the middle), click it without Shift. It becomes a building part of its own with its own height and is cut out of the outer part, whichever of the two you select first, even if they share an edge.
  3. Several contours as one area: if a building part consists of several contours in the plan, click the first contour in “Building part” mode. Each click while holding Shift (or with the switch “Add contours (like Shift)” below the mode buttons turned on) adds another contour straight to the part you selected last, with no confirmation. If you remove that part, the part selected before it applies, as long as it still exists. A Shift-click on a contour of the part removes it again. Roofy closes gaps of up to 2 cm between the contours itself; if they still do not touch, Roofy shows the gap and the part stays as it was. Then close the contours in your CAD software or select them individually. “Split” in the list separates the part into its contours again.
  4. Courtyard: in “Courtyard” mode, click a contour inside a part. It is cut out as a hole; the ring roof is split into two roof surfaces along the shortest cuts between courtyard and outer edge.
  5. Confirm size, unit and scale: the next step, “Size, unit and scale”, shows width and depth of all chosen parts in metres, the detected unit (mm, cm or m) and the scale: 1:1, 1:50, 1:100, 1:200, 1:500 or a custom value. For plans drawn in paper units, Roofy suggests the scale from the size of the plan and says so. If the size is wrong, switch the unit or the scale; the value in the file is only a hint. The custom value may have up to two decimal places, for example 1:1.6. Dimensions and model follow your choice straight away; Roofy reads the list of contours again by itself as soon as you choose a unit or a scale or leave the “Custom value” field (so that, for example, chimneys that fell below the minimum area at the old scale appear). While reading again, “Next” is locked; the chosen parts, courtyards and obstacles are kept as far as their contours still exist. If reading again fails, Roofy shows the reason and “Read again”.
  6. Reference length: if you know the true length of a distance in the plan, for example a façade, choose “Measure a reference length” in the same step, click two corners of that distance (the point snaps to a nearby contour corner) and enter the length under “True length in m”. Roofy shows the matching scale exactly (with two decimal places) and rounded to the nearest standard scale; you apply it with “Use rounded value” or “Use exact value”. If another unit fits better, Roofy also offers “Use unit and scale”. Every apply closes the reference measurement, confirms the scale with a line and reads the contours again. Escape cancels the measurement.

Choose obstacles

Roof structures already drawn in the floor plan (chimneys, skylights, ventilation units, lift overruns) are adopted as obstacles. Roofy places them as boxes on the roof and creates them in 2D as closed measurement lines. Structures that are not in the plan you add later (section “Adding further obstacles”).

  1. Choose “Obstacle” mode: contours of up to 25 m² that lie entirely within a building part can be clicked. A second click on the same obstacle removes it; the click chain to the next larger contour applies here too.
  2. Several in a row: obstacles appear in the parts list under their building part as “Obstacle 1, 2 ...” with dimensions and area. At most 50 obstacles per model. Two obstacles that touch or lie closer than 0.2 m to each other stay separate in the model with their own height and box; in 2D and in Solar they get one shared outline, and the picker shows a note about it.
  3. Note on large contours: if an obstacle takes up at least a quarter of the roof surface of the part, Roofy shows a note. Check whether it really is a roof structure or rather a separate building part.
  4. Name: in the “Style and heights” step each obstacle has a “Name” field next to “Height in m”. Roofy suggests the block or layer name of the contour from the file, for example “CHIMNEY”; if there is none, the field stays empty. The name carries through to Solar and appears there in the obstacle list; you can change it later via “Model parameters” and “Regenerate”.
  5. Check line: before generating (in the “Generate” step and in the model parameters), Roofy reports small closed contours inside a part that are neither an obstacle nor a courtyard; it counts contours under 5 per cent of the part area and up to 25 m². “Show” highlights them in the plan, for example to select a chimney in “Obstacle” mode after all. “Apply anyway” generates the model without them.

Heights and parapet

In the “Style and heights” step you set the look and the heights of the model per building part, plus the height of each obstacle. A small plan view shows the selected parts with their number; pointing at a part in the plan or in the list highlights both.

  1. Style: Residential (light render with rows of windows) or Factory (grey with a skylight band). The style sets the total height to its default (Residential 10 m, Factory 15 m); enter your own height afterwards.
  2. Total height per part in m: the ground is at height 0, the model carries relative heights without terrain.
  3. Parapet (optional): empty means no parapet. With a parapet height the parapet thickness field appears (default 0.25 m, 0.05 to 1 m); the roof surface reaches to the inner edge of the parapet.
  4. Obstacle height: one “Height in m” field per obstacle, default 1 m, allowed 0.1 to 10 m, measured from the roof surface of the part. With “Area only” there is no height and no 3D geometry, only the measurement line in 2D.

North direction

The north direction feeds the solar layout (south orientation, east-west, compass directions). Roofy reads it from the plan where possible; otherwise the top of the plan counts as north.

  1. Check the source: the wizard shows where the direction comes from: from the plan (plan header, geodata or north arrow block) or the assumption “up is north”.
  2. Rotate the arrow: drag the north arrow or set the angle until the arrow points north on the plan.
  3. Changing it later: via “Model parameters” and “Regenerate” the north direction can be changed as long as nothing has been measured, drawn or laid out in the session. After that it is locked; deleting the measurements, drawn sections and the layout lifts the lock again, otherwise a new session helps.

Generate

With “Generate model”, Roofy builds the flat-roof model in the background. Generating counts like a 3D run.

  1. Entitlement: generating needs Roofy Pro or Enterprise; without a subscription it uses the free project that is still open.
  2. Result: the 2D view shows the plan as background, the 3D model shows the building parts with parapet and the obstacles as boxes. The roof surfaces are prefilled and labelled per part as flat-roof sections.
  3. Obstacles in 2D and 3D: every chosen obstacle lies on the roof as a closed measurement line. In 3D the obstacle height can be measured because the height map carries the obstacle.

Adding further obstacles

Roof structures that are not in the plan or do not form a closed contour there get into the model in three ways: as measurement lines in 2D, directly in Solar or via the model parameters.

  1. In 2D as measurement lines: in “Measure & Split” mode (key M) draw a closed sequence of measurement lines around the structure, for example with the rectangle tool (key R, three clicks give four measurement lines). Roofy recognises the outline when at least three lines take part, the end points lie no more than 15 cm apart and no more than two lines meet at any point (no T junction, no shared edge of two rectangles). Every corner must lie on the roof surface (up to 15 cm beyond the edge is allowed) and at most 10.5 m above or 0.5 m below the roof plane; the outline must not cross itself. With Solar switched on, the outline is adopted as an obstacle at once, otherwise the next time you switch Solar on; “Delete” in the obstacle list deselects it permanently. The structure gets no box in the 3D model; only obstacles from the plan carry a height.
  2. Directly in Solar: in the “Obstacles” step choose the surface and draw the obstacle on the roof surface with “Rectangle” (set the first side with two clicks or one drag, then pull out the width; the rectangle may be rotated) or “Polygon” (click points; from three points a click on the first point closes the obstacle). The tool stays active until you end it with Escape or the button. An obstacle drawn in Solar is an area in the roof plane without height and without 3D geometry; it only affects the layout: modules keep the “Obstacle clearance” from the rules (0 to 500 cm; at 0 cm modules may touch the obstacle but never lie on it). At most 50 obstacles per surface. Remove it with “Delete” in the list or with a right click on the obstacle.
  3. Via the model parameters: open “Model parameters” in the session and use “Change outline and parts” to open the contour picker in “Obstacle” mode and add or remove plan contours as obstacles; per obstacle “Height in m” or “Area only”. “Regenerate” rebuilds the outlines and boxes of the affected part; Roofy removes the previously adopted obstacles from the solar layout, and Solar adopts the new outlines the next time it is opened. Only contours present in the plan can be chosen this way; for everything else use the two ways above.

Change model parameters

In the session, “Model parameters” opens the wizard for changes to the existing model. Regenerating uses no further free project and does not count as a new 3D run; “Regenerate” stays locked until something has changed.

  1. Heights, parapet, style: change the values per part and choose “Regenerate”. Measurements and solar layouts are kept as long as the outline and parts stay the same.
  2. Obstacles: change the height or “Area only” per obstacle; via “Change outline and parts” you add or remove plan contours in “Obstacle” mode. A changed obstacle rebuilds only the obstacle measurement lines and boxes of its part; roof surfaces are kept. Roofy removes the previously adopted obstacles of the part from the solar layout, and Solar adopts the new outlines the next time it is opened.
  3. Outline and parts: solar surfaces on changed parts are lost when regenerating; Roofy shows the affected surfaces beforehand and asks for confirmation.
  4. North direction: only changeable as long as nothing has been measured, drawn or laid out. After that it is locked; deleting the measurements, drawn sections and the layout lifts the lock, otherwise a new session helps.

Quick checklist plan (DXF or DWG)

  • DXF or DWG floor plan of up to 25 MB; if a DWG causes problems, save the plan as DXF in your CAD software.
  • Click the outline yourself; check the unit (mm, cm, m) and the scale (1:1 to 1:500 or your own value, if needed via a reference length) via width and depth.
  • Choose every building part with its own height as its own contour, courtyards as holes; for a part made of several contours, click the first and add the others with Shift-click or the switch “Add contours (like Shift)”.
  • Adopt roof structures of up to 25 m² in Obstacle mode: at most 50; obstacles close together get one shared outline in Solar.
  • Per obstacle a height of 0.1 to 10 m (default 1 m) or Area only.
  • Structures without a contour in the plan: draw them in 2D as closed measurement lines or set them in Solar as a rectangle or polygon.
  • Then measure and lay out as in a drone session; what differs for Solar in the plan model is in the chapter Solar module layout.
  • Set parapet height and thickness if present.
  • Check the north direction before measuring and laying out; afterwards it is locked.
  • Generating needs Pro, Enterprise or the free project; regenerating uses no further run.

Next step

Measure the roof

After generating, you measure in the plan model as in a drone session: polygons, measurement lines, height map and keyboard shortcuts.

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