Arch Site

From FreeCAD Documentation
This page has been updated for that version.

Arch Site

Menu location
3D/BIM → Site
Default shortcut
Introduced in version
See also


The Arch Site is a special object that combines properties of a standard FreeCAD group object and Arch objects. It is particularly suited for representing a whole project site, or terrain. In IFC-based architectural work, it is mostly used to organize your model, by containing building objects. The site is also used to manage and display a physical terrain, and can compute volumes of earth to be added or removed.


  1. Optionally, select one or more objects to be included in your new site.
  2. Press the Site button, or press the S then I keys.


  • After creating a site, you can add objects to it by drag and dropping them in the Tree view or by using the Arch Add tool. This only determines which objects are part of the given site, and has no effect on the terrain.
  • You can remove objects from a site by drag and dropping them out of it in the Tree view or by using the Arch Remove tool.
  • You can add a terrain object by editing the Site's DataTerrain property. The terrain can be an open shell or (introduced in version 0.21) a solid.
  • You can add volumes to be added or subtracted from the base terrain, by double-clicking the Site, and adding objects to its Additions or Subtractions groups. The objects must be solids.
  • The DataExtrusion Vector property can be used to solve some problems that can appear when the terrain is an open shell and there are additions and/or subtractions. In order to perform those additions/subtractions, the open shell is extruded into a solid, which is then appropriately unioned/subtracted. Depending on the terrain topology, this extrusion might fail with the default extrusion vector. You might then be able to remedy the problem by changing this to a different value. This property is ignored if the terrain is a solid.



  • DataTerrain: The base terrain of this site
  • DataAddress: The street and housenumber of this site
  • DataPostal Code: The postal or zip code of this site
  • DataCity: The city of this site
  • DataCountry: The country of this site
  • DataLatitude: The latitude of this site
  • DataLongitude: The longitude of this site
  • DataUrl: An url that shows this site in a mapping website
  • DataProjected Area: The area of the projection of this object onto the XY plane
  • DataPerimeter: The perimeter length of this terrain
  • DataAddition Volume: The volume of earth to be added to this terrain
  • DataSubtraction Volume: The volume of earth to be removed from this terrain
  • DataExtrusion Vector: An extrusion vector to use when performing boolean operations
  • DataRemove Splitter: Remove splitters from the resulting shape
  • DataDeclination: The angle between the true North and the North direction in this document, that is, the Y axis. This means that by default North points to the Y axis, and East to the X axis; the angle increments counterclockwise. This property was previously known as DataNorth Deviation.
  • DataEPW File: Allow to attach an EPW file from the Ladybug EPW data website to this site. This is needed to display wind rose diagrams


  • ViewSolar Diagram: Shows or hides the solar diagram
  • ViewSolar Diagram Color: The color of the solar diagram
  • ViewSolar Diagram Position: The position of the solar diagram
  • ViewSolar Diagram Scale: The scale of the solar diagram
  • ViewWind Rose: Shows or hides the wind rose diagram (requires the EPW File data property filled, and the Ladybug Python module installed (see below)

Typical workflow

Start by creating an object that represents your terrain. For example, it is easy to import mesh data, that can be turned into a Part Shape from menu Part → Create Shape from Mesh. Then, create a Site object, and set its DataTerrain property to the Part we just created:

Create some volumes (they must be solids) that represent the areas that you wish to be excavated or filled. Double-click the Site object in the Tree View, and add these volumes to the Additions or Subtractions groups. Click OK.

The site geometry will be recomputed and the areas, perimeter, and volumes properties recalculated.

Solar and wind diagrams

If Ladybug is installed on your system, Arch Sites can display a solar diagram and/or a wind rose. For this, DataLongitude, DataLatitude and DataDeclination (previously DataNorth Deviation) must be correctly set, and ViewSolar Diagram or ViewWind Rose set to true.

Note: If you don't have Ladybug, pysolar is still supported to generate solar diagrams, but not wind roses. Pysolar 0.7 or above is required; this version only works with Python 3. If you require this feature with Python 2, you should have Pysolar 0.6 as this is the last version that works with Python 2. However, Ladybug is a much more powerful tool that will probably be used more in the future, so we recommend using it instead of pysolar. Ladybug can be installed simply via pip.


See also: Arch API and FreeCAD Scripting Basics.

The Site tool can be used in macros and from the Python console by using the following function:

Site = makeSite(objectslist=None, baseobj=None, name="Site")
  • Creates a Site object from objectslist, which is a list of objects, or baseobj, which is a Shape or Terrain.


import FreeCAD, Draft, Arch

p1 = FreeCAD.Vector(0, 0, 0)
p2 = FreeCAD.Vector(2000, 0, 0)
baseline = Draft.makeLine(p1, p2)
Wall = Arch.makeWall(baseline, length=None, width=150, height=2000)

Building = Arch.makeBuilding([Wall])
Site = Arch.makeSite([Building])


Solar diagram

As long as the pysolar module is present, a solar diagram can be added to the site. Set the longitude, latitude and declination angles as appropriate, as well as an adequate scale for the size of your model.

Please note that Pysolar 0.7 or above is required, and this version only works with Python 3.

Site.Longitude = -46.38
Site.Latitude = -23.33
Site.Declination = 30
#Site.Compass = True

Site.ViewObject.SolarDiagram = True
Site.ViewObject.SolarDiagramScale = 10000

Solar diagram independent of Site

A solar diagram can be created with the following function, independently of any site.

Node = makeSolarDiagram(longitude, latitude, scale=1, complete=False)
  • Creates a solar diagram as a Pivy node, using longitude and latitude, with an optional scale.
  • If complete is True, the 12 months are drawn, which shows the full solar analemma.
import FreeCADGui, Arch

Node = Arch.makeSolarDiagram(-46.38, -23.33, scale=10000, complete=True)