You can now extend beams to walls.

src/blenderbim/blenderbim/bim/module/model/slab.py

@@ -622,6 +622,7 @@ class EnableEditingExtrusionProfile(bpy.types.Operator, tool.Ifc.Operator):
 
         bpy.ops.object.mode_set(mode="EDIT")
         DecorationsHandler.install(context)
+        if not bpy.app.background:
             bpy.ops.wm.tool_set_by_id(name="bim.cad_tool")
         return {"FINISHED"}
 

src/blenderbim/blenderbim/bim/module/model/workspace.py

@@ -464,14 +464,44 @@ class Hotkey(bpy.types.Operator, tool.Ifc.Operator):
     def hotkey_S_E(self):
         if not bpy.context.selected_objects:
             return
-        elif self.active_material_usage == "LAYER2":
+
-            bpy.ops.bim.join_wall(join_type="T")
+        selected_usages = {}
-        elif self.active_material_usage == "LAYER3":
+        for obj in bpy.context.selected_objects:
-            if not bpy.context.active_object:
+            element = tool.Ifc.get_entity(obj)
-                pass
+            if not element:
-            elif bpy.context.active_object.mode == "OBJECT":
+                obj.select_set(False)
+                continue
+            usage = tool.Model.get_usage_type(element)
+            if not usage:
+                obj.select_set(False)
+                continue
+            selected_usages.setdefault(usage, []).append(obj)
+
+        if len(bpy.context.selected_objects) == 1:
+            if self.active_material_usage == "LAYER3":
+                # Edit LAYER2 profile
+                if bpy.context.active_object and bpy.context.active_object.mode == "OBJECT":
                     bpy.ops.bim.enable_editing_extrusion_profile()
+            elif self.active_material_usage == "LAYER2":
+                # Extend LAYER2 to cursor
+                bpy.ops.bim.join_wall(join_type="T")
             elif self.active_material_usage == "PROFILE":
+                # Extend PROFILE to cursor
+                bpy.ops.bim.extend_profile(join_type="T")
+        elif self.active_material_usage == "LAYER2" and selected_usages.get("PROFILE", []):
+            # Extend PROFILEs to LAYER2
+            [o.select_set(False) for o in selected_usages.get("LAYER3", [])]
+            [o.select_set(False) for o in selected_usages.get("LAYER2", []) if o != bpy.context.active_object]
+            bpy.ops.bim.extend_profile(join_type="T")
+        elif self.active_material_usage == "LAYER2":
+            # Extend LAYER2s to LAYER2
+            [o.select_set(False) for o in selected_usages.get("LAYER3", [])]
+            [o.select_set(False) for o in selected_usages.get("PROFILE", [])]
+            bpy.ops.bim.join_wall(join_type="T")
+        elif self.active_material_usage == "PROFILE":
+            # Extend PROFILEs to PROFILE
+            [o.select_set(False) for o in selected_usages.get("LAYER3", [])]
+            [o.select_set(False) for o in selected_usages.get("LAYER2", [])]
             bpy.ops.bim.extend_profile(join_type="T")
 
     def hotkey_S_F(self):