diff --git a/src/Mod/Arch/ArchSite.py b/src/Mod/Arch/ArchSite.py
index a989a23e8..deb201d82 100644
--- a/src/Mod/Arch/ArchSite.py
+++ b/src/Mod/Arch/ArchSite.py
@@ -23,7 +23,7 @@
 #*                                                                         *
 #***************************************************************************
 
-import FreeCAD,Draft,ArchCommands,ArchFloor
+import FreeCAD,Draft,ArchCommands,ArchFloor,math,re,datetime
 if FreeCAD.GuiUp:
     import FreeCADGui
     from PySide import QtCore, QtGui
@@ -67,6 +67,172 @@ def makeSite(objectslist=None,baseobj=None,name="Site"):
     return obj
 
 
+def makeSolarDiagram(longitude,latitude,scale=1,complete=False):
+    """makeSolarDiagram(longitude,latitude,[scale,complete]):
+    returns a solar diagram as a pivy node. If complete is
+    True, the 12 months are drawn"""
+
+    try:
+        import Pysolar
+    except:
+        print("Pysolar is not installed. Unable to generate solar diagrams")
+        return None
+    from pivy import coin
+    
+    if not scale:
+        return None
+
+    def toNode(shape):
+        "builds a pivy node from a simple linear shape"
+        from pivy import coin
+        buf = shape.writeInventor(2,0.01)
+        buf = buf.replace("\n","")
+        pts = re.findall("point \[(.*?)\]",buf)[0]
+        pts = pts.split(",")
+        pc = []
+        for p in pts:
+            v = p.strip().split()
+            pc.append([float(v[0]),float(v[1]),float(v[2])])
+        coords = coin.SoCoordinate3()
+        coords.point.setValues(0,len(pc),pc)
+        line = coin.SoLineSet()
+        line.numVertices.setValue(-1)
+        item = coin.SoSeparator()
+        item.addChild(coords)
+        item.addChild(line)
+        return item
+
+    circles = []
+    sunpaths = []
+    hourpaths = []
+    circlepos = []
+    hourpos = []
+
+    # build the base circle + number positions
+    import Part
+    for i in range(1,9):
+        circles.append(Part.makeCircle(scale*(i/8.0)))
+    for ad in range(0,360,15):
+        a = math.radians(ad)
+        p1 = FreeCAD.Vector(math.cos(a)*scale,math.sin(a)*scale,0)
+        p2 = FreeCAD.Vector(math.cos(a)*scale*0.125,math.sin(a)*scale*0.125,0)
+        p3 = FreeCAD.Vector(math.cos(a)*scale*1.08,math.sin(a)*scale*1.08,0)
+        circles.append(Part.Line(p1,p2).toShape())
+        circlepos.append((ad,p3))
+
+    # build the sun curves at solstices and equinoxe
+    year = datetime.datetime.now().year
+    hpts = [ [] for i in range(24) ]
+    m = [(6,21),(7,21),(8,21),(9,21),(10,21),(11,21),(12,21)]
+    if complete:
+        m.extend([(1,21),(2,21),(3,21),(4,21),(5,21)])
+    for i,d in enumerate(m):
+        pts = []
+        for h in range(24):
+            dt = datetime.datetime(year,d[0],d[1],h)
+            alt = math.radians(Pysolar.solar.GetAltitudeFast(latitude,longitude,dt))
+            az = Pysolar.solar.GetAzimuth(latitude,longitude,dt)
+            az = -90 + az # pysolar's zero is south
+            if az < 0:
+                az = 360 + az
+            az = math.radians(az)
+            zc = math.sin(alt)*scale
+            ic = math.cos(alt)*scale
+            xc = math.cos(az)*ic
+            yc = math.sin(az)*ic
+            p = FreeCAD.Vector(xc,yc,zc)
+            pts.append(p)
+            hpts[h].append(p)
+            if i in [0,6]:
+                ep = FreeCAD.Vector(p)
+                ep.multiply(1.08)
+                if ep.z >= 0:
+                    if h == 12:
+                        if i == 0:
+                            h = "SUMMER"
+                        else:
+                            h = "WINTER"
+                        if latitude < 0:
+                            if h == "SUMMER":
+                                h = "WINTER"
+                            else:
+                                h = "SUMMER"
+                    hourpos.append((h,ep))
+        if i < 7:
+            sunpaths.append(Part.makePolygon(pts))
+    for h in hpts:
+        if complete:
+            h.append(h[0])
+        hourpaths.append(Part.makePolygon(h))
+
+    # cut underground lines
+    sz = 2.1*scale
+    cube = Part.makeBox(sz,sz,sz)
+    cube.translate(FreeCAD.Vector(-sz/2,-sz/2,-sz))
+    sunpaths = [sp.cut(cube) for sp in sunpaths]
+    hourpaths = [hp.cut(cube) for hp in hourpaths]
+
+    # build nodes
+    ts = 0.005*scale # text scale
+    mastersep = coin.SoSeparator()
+    circlesep = coin.SoSeparator()
+    numsep = coin.SoSeparator()
+    pathsep = coin.SoSeparator()
+    hoursep = coin.SoSeparator()
+    hournumsep = coin.SoSeparator()
+    mastersep.addChild(circlesep)
+    mastersep.addChild(numsep)
+    mastersep.addChild(pathsep)
+    mastersep.addChild(hoursep)
+    for item in circles:
+        circlesep.addChild(toNode(item))
+    for item in sunpaths:
+        for w in item.Edges:
+            pathsep.addChild(toNode(w))
+    for item in hourpaths:
+        for w in item.Edges:
+            hoursep.addChild(toNode(w))
+    for p in circlepos:
+        text = coin.SoText2()
+        s = p[0]-90
+        s = -s
+        if s > 360:
+            s = s - 360
+        if s < 0:
+            s = 360 + s
+        if s == 0:
+            s = "N"
+        elif s == 90:
+            s = "E"
+        elif s == 180:
+            s = "S"
+        elif s == 270:
+            s = "W"
+        else:
+            s = str(s)
+        text.string = s
+        text.justification = coin.SoText2.CENTER
+        coords = coin.SoTransform()
+        coords.translation.setValue([p[1].x,p[1].y,p[1].z])
+        coords.scaleFactor.setValue([ts,ts,ts])
+        item = coin.SoSeparator()
+        item.addChild(coords)
+        item.addChild(text)
+        numsep.addChild(item)
+    for p in hourpos:
+        text = coin.SoText2()
+        s = str(p[0])
+        text.string = s
+        text.justification = coin.SoText2.CENTER
+        coords = coin.SoTransform()
+        coords.translation.setValue([p[1].x,p[1].y,p[1].z])
+        coords.scaleFactor.setValue([ts,ts,ts])
+        item = coin.SoSeparator()
+        item.addChild(coords)
+        item.addChild(text)
+        numsep.addChild(item)
+    return mastersep
+
 
 class _CommandSite:
     "the Arch Site command definition"
@@ -130,6 +296,7 @@ class _Site(ArchFloor._Floor):
         obj.addProperty("App::PropertyString","Country","Arch",QT_TRANSLATE_NOOP("App::Property","The country of this site"))
         obj.addProperty("App::PropertyFloat","Latitude","Arch",QT_TRANSLATE_NOOP("App::Property","The latitude of this site"))
         obj.addProperty("App::PropertyFloat","Longitude","Arch",QT_TRANSLATE_NOOP("App::Property","The latitude of this site"))
+        obj.addProperty("App::PropertyAngle","NorthDeviation","Arch",QT_TRANSLATE_NOOP("App::Property","Angle between the true North and the North direction in this document"))
         obj.addProperty("App::PropertyLength","Elevation","Arch",QT_TRANSLATE_NOOP("App::Property","The elevation of level 0 of this site"))
         obj.addProperty("App::PropertyString","Url","Arch",QT_TRANSLATE_NOOP("App::Property","An url that shows this site in a mapping website"))
         obj.addProperty("App::PropertyLinkList","Group","Arch",QT_TRANSLATE_NOOP("App::Property","The objects that are part of this site"))
@@ -269,6 +436,12 @@ class _ViewProviderSite(ArchFloor._ViewProviderFloor):
 
     def __init__(self,vobj):
         ArchFloor._ViewProviderFloor.__init__(self,vobj)
+        vobj.addProperty("App::PropertyBool","SolarDiagram","Arch",QT_TRANSLATE_NOOP("App::Property","Show solar diagram or not"))
+        vobj.addProperty("App::PropertyFloat","SolarDiagramScale","Arch",QT_TRANSLATE_NOOP("App::Property","The scale of the solar diagram"))
+        vobj.addProperty("App::PropertyVector","SolarDiagramPosition","Arch",QT_TRANSLATE_NOOP("App::Property","The position of the solar diagram"))
+        vobj.addProperty("App::PropertyColor","SolarDiagramColor","Arch",QT_TRANSLATE_NOOP("App::Property","The color of the solar diagram"))
+        vobj.SolarDiagramScale = 1
+        vobj.SolarDiagramColor = (0.16,0.16,0.25)
 
     def getIcon(self):
         import Arch_rc
@@ -296,6 +469,52 @@ class _ViewProviderSite(ArchFloor._ViewProviderFloor):
     def unsetEdit(self,vobj,mode):
         FreeCADGui.Control.closeDialog()
         return False
+        
+    def attach(self,vobj):
+        ArchFloor._ViewProviderFloor.attach(self,vobj)
+        from pivy import coin
+        self.diagramsep = coin.SoSeparator()
+        self.color = coin.SoBaseColor()
+        self.coords = coin.SoTransform()
+        self.diagramswitch = coin.SoSwitch()
+        self.diagramswitch.whichChild = -1
+        self.diagramswitch.addChild(self.diagramsep)
+        self.diagramsep.addChild(self.coords)
+        self.diagramsep.addChild(self.color)
+        vobj.Annotation.addChild(self.diagramswitch)
+        
+    def updateData(self,obj,prop):
+        if prop in ["Longitude","Latitude"]:
+            self.onChanged(obj.ViewObject,"SolarDiagram")
+        elif prop == "NorthDeviation":
+            self.onChanged(obj.ViewObject,"SolarDiagramPosition")
+        
+    def onChanged(self,vobj,prop):
+        if prop == "SolarDiagramPosition":
+            if hasattr(vobj,"SolarDiagramPosition"):
+                p = vobj.SolarDiagramPosition
+                self.coords.translation.setValue([p.x,p.y,p.z])
+            if hasattr(vobj.Object,"NorthDeviation"):
+                from pivy import coin
+                self.coords.rotation.setValue(coin.SbVec3f((0,0,1)),math.radians(vobj.Object.NorthDeviation.Value))
+        elif prop == "SolarDiagramColor":
+            if hasattr(vobj,"SolarDiagramColor"):
+                l = vobj.SolarDiagramColor
+                self.color.rgb.setValue([l[0],l[1],l[2]])
+        elif "SolarDiagram" in prop:
+            if hasattr(self,"diagramnode"):
+                self.diagramsep.removeChild(self.diagramnode)
+                del self.diagramnode
+            if hasattr(vobj,"SolarDiagram") and hasattr(vobj,"SolarDiagramScale"):
+                if vobj.SolarDiagram:
+                    self.diagramnode = makeSolarDiagram(vobj.Object.Longitude,vobj.Object.Latitude,vobj.SolarDiagramScale)
+                    if self.diagramnode:
+                        self.diagramsep.addChild(self.diagramnode)
+                        self.diagramswitch.whichChild = 0
+                    else:
+                        del self.diagramnode
+                else:
+                    self.diagramswitch.whichChild = -1
 
 
 if FreeCAD.GuiUp: