diff --git a/src/bonsai/bonsai/bim/import_ifc.py b/src/bonsai/bonsai/bim/import_ifc.py
index 90855053c8..c30bbca3db 100644
--- a/src/bonsai/bonsai/bim/import_ifc.py
+++ b/src/bonsai/bonsai/bim/import_ifc.py
@@ -1126,7 +1126,7 @@ class IfcImporter:
             if parts:
                 relating_obj = tool.Ifc.get_object(element)
                 if relating_obj:
-                    tool.Aggregate.constrain_parts_to_aggregate(relating_obj)
+                    tool.Aggregate.constrain_all_parts_to_aggregate(relating_obj)
         bpy.context.scene.BIMAggregateProperties.aggregate_decorator = True
 
 
diff --git a/src/bonsai/bonsai/bim/module/aggregate/decorator.py b/src/bonsai/bonsai/bim/module/aggregate/decorator.py
index 362c5baa4b..5726d063b9 100644
--- a/src/bonsai/bonsai/bim/module/aggregate/decorator.py
+++ b/src/bonsai/bonsai/bim/module/aggregate/decorator.py
@@ -343,6 +343,8 @@ class AggregateModeDecorator:
         new_objs = [o for o in new_objs if o.data]
         for obj in new_objs:
             element = tool.Ifc.get_entity(obj)
+            if (aggregate := ifcopenshell.util.element.get_aggregate(element)) == tool.Ifc.get_entity(props.editing_aggregate):
+                continue
             if element and element.is_a("IfcElement"):
                 data = ItemDecorator.get_obj_data(obj)
                 if data:
diff --git a/src/bonsai/bonsai/bim/module/aggregate/operator.py b/src/bonsai/bonsai/bim/module/aggregate/operator.py
index 04c55d19d4..8555a4168c 100644
--- a/src/bonsai/bonsai/bim/module/aggregate/operator.py
+++ b/src/bonsai/bonsai/bim/module/aggregate/operator.py
@@ -67,7 +67,7 @@ class BIM_OT_aggregate_assign_object(bpy.types.Operator, tool.Ifc.Operator):
                     relating_obj=relating_obj,
                     related_obj=obj,
                 )
-                tool.Aggregate.constrain_parts_to_aggregate(relating_obj)
+                tool.Aggregate.constrain_part_to_aggregate(obj, relating_obj)
                 props = context.scene.BIMAggregateProperties
                 if relating_obj == props.editing_aggregate and props.in_aggregate_mode:
                     new_editing_obj = props.editing_objects.add()
@@ -185,7 +185,7 @@ class BIM_OT_add_aggregate(bpy.types.Operator, tool.Ifc.Operator):
                     element_obj=aggregate,
                 )
             core.assign_object(tool.Ifc, tool.Aggregate, tool.Collector, relating_obj=aggregate, related_obj=obj)
-            tool.Aggregate.constrain_parts_to_aggregate(aggregate)
+            tool.Aggregate.constrain_all_parts_to_aggregate(aggregate)
 
     def create_aggregate(self, context, ifc_class, aggregate_name):
         aggregate = bpy.data.objects.new(aggregate_name, None)
@@ -424,13 +424,17 @@ class BIM_OT_aggregate_assing_new_objects_in_aggregate_mode(bpy.types.Operator):
         new_objs = [o for o in new_objs if o.data]
         for obj in new_objs:
             element = tool.Ifc.get_entity(obj)
+            if (aggregate := ifcopenshell.util.element.get_aggregate(element)) == tool.Ifc.get_entity(props.editing_aggregate):
+                continue
             if element and element.is_a("IfcElement"):
                 obj.select_set(True)
                 editing_obj = props.editing_objects.add()
                 editing_obj.obj = obj
                 props.editing_aggregate.select_set(True)
+        context.view_layer.objects.active = new_objs[0]
         self.relating_object = tool.Ifc.get_entity(props.editing_aggregate).id()
         self.related_object = tool.Ifc.get_entity(obj).id()
+
         BIM_OT_aggregate_assign_object._execute(self, context)
 
         return {"FINISHED"}
diff --git a/src/bonsai/bonsai/tool/aggregate.py b/src/bonsai/bonsai/tool/aggregate.py
index 55cdf57427..926f98fdbc 100644
--- a/src/bonsai/bonsai/tool/aggregate.py
+++ b/src/bonsai/bonsai/tool/aggregate.py
@@ -85,7 +85,7 @@ class Aggregate(bonsai.core.tool.Aggregate):
         return parts
 
     @classmethod
-    def constrain_parts_to_aggregate(cls, aggregate: bpy.types.Object):
+    def constrain_all_parts_to_aggregate(cls, aggregate: bpy.types.Object):
         agg_element = tool.Ifc.get_entity(aggregate)
         parts = ifcopenshell.util.element.get_parts(agg_element)
         parts_objs = [tool.Ifc.get_object(p) for p in parts]