diff --git a/src/blenderbim/blenderbim/bim/module/material/prop.py b/src/blenderbim/blenderbim/bim/module/material/prop.py
index 9374ac67cf..d8737ad21e 100644
--- a/src/blenderbim/blenderbim/bim/module/material/prop.py
+++ b/src/blenderbim/blenderbim/bim/module/material/prop.py
@@ -123,7 +123,7 @@ class Material(PropertyGroup):
     name: StringProperty(name="Name")
     ifc_definition_id: IntProperty(name="IFC Definition ID")
     is_category: BoolProperty(name="Is Category", default=False)
-    is_expanded: BoolProperty(name="Is Expanded", default=True)
+    is_expanded: BoolProperty(name="Is Expanded", default=False)
     has_style: BoolProperty(name="Has Style", default=True)
     total_elements: IntProperty(name="Total Elements")
 
diff --git a/src/blenderbim/blenderbim/tool/material.py b/src/blenderbim/blenderbim/tool/material.py
index 6dbb345311..e52b7abbf0 100644
--- a/src/blenderbim/blenderbim/tool/material.py
+++ b/src/blenderbim/blenderbim/tool/material.py
@@ -60,7 +60,7 @@ class Material(blenderbim.core.tool.Material):
     @classmethod
     def import_material_definitions(cls, material_type: str) -> None:
         props = bpy.context.scene.BIMMaterialProperties
-        expanded_categories = {m.name for m in props.materials if m.is_expanded}
+        expanded_categories = {m.name for m in props.materials if m.is_category and m.is_expanded}
         props.materials.clear()
         get_name = lambda x: x.Name or "Unnamed"
         if material_type == "IfcMaterialLayerSet":