diff --git a/src/blenderbim/blenderbim/bim/ifc.py b/src/blenderbim/blenderbim/bim/ifc.py
index 25fcdf9148..5b400d2284 100644
--- a/src/blenderbim/blenderbim/bim/ifc.py
+++ b/src/blenderbim/blenderbim/bim/ifc.py
@@ -84,7 +84,10 @@ class IfcStore:
             ifc_hash = hashlib.md5(ifc_key.encode("utf-8")).hexdigest()
             IfcStore.cache_path = os.path.join(bpy.context.scene.BIMProperties.data_dir, "cache", f"{ifc_hash}.h5")
             cache_settings = ifcopenshell.geom.settings()
-            IfcStore.cache = ifcopenshell.geom.serializers.hdf5(IfcStore.cache_path, cache_settings)
+            try:
+                IfcStore.cache = ifcopenshell.geom.serializers.hdf5(IfcStore.cache_path, cache_settings)
+            except:
+                return
         return IfcStore.cache
 
     @staticmethod
@@ -255,7 +258,9 @@ class IfcStore:
         except:
             pass
 
-        if obj:
+        if element.is_a("IfcSurfaceStyle"):
+            obj.BIMMaterialProperties.ifc_style_id = 0
+        elif obj:
             obj.BIMObjectProperties.ifc_definition_id = 0
 
     @staticmethod
diff --git a/src/blenderbim/blenderbim/bim/import_ifc.py b/src/blenderbim/blenderbim/bim/import_ifc.py
index 331d43a782..8c9f181bde 100644
--- a/src/blenderbim/blenderbim/bim/import_ifc.py
+++ b/src/blenderbim/blenderbim/bim/import_ifc.py
@@ -625,7 +625,9 @@ class IfcImporter:
             )
         else:
             iterator = ifcopenshell.geom.iterator(self.settings, self.file, include=products)
-        iterator.set_cache(IfcStore.get_cache())
+        cache = IfcStore.get_cache()
+        if cache:
+            iterator.set_cache(cache)
         valid_file = iterator.initialize()
         if not valid_file:
             return results
@@ -771,7 +773,9 @@ class IfcImporter:
             )
         else:
             iterator = ifcopenshell.geom.iterator(self.settings_2d, self.file, include=products)
-        iterator.set_cache(IfcStore.get_cache())
+        cache = IfcStore.get_cache()
+        if cache:
+            iterator.set_cache(cache)
         valid_file = iterator.initialize()
         if not valid_file:
             return results
diff --git a/src/blenderbim/blenderbim/bim/module/root/operator.py b/src/blenderbim/blenderbim/bim/module/root/operator.py
index 2f88a204a0..fab321445a 100644
--- a/src/blenderbim/blenderbim/bim/module/root/operator.py
+++ b/src/blenderbim/blenderbim/bim/module/root/operator.py
@@ -316,8 +316,8 @@ class UnlinkObject(bpy.types.Operator):
                 IfcStore.unlink_element(obj=obj)
             for material_slot in obj.material_slots:
                 if material_slot.material:
-                    blenderbim.core.style.unlink_style(tool.Style, obj=material_slot.material)
-                    blenderbim.core.material.unlink_material(tool.Material, obj=material_slot.material)
+                    blenderbim.core.style.unlink_style(tool.Ifc, tool.Style, obj=material_slot.material)
+                    blenderbim.core.material.unlink_material(tool.Ifc, obj=material_slot.material)
             if "Ifc" in obj.name and "/" in obj.name:
                 obj.name = "/".join(obj.name.split("/")[1:])
         return {"FINISHED"}
diff --git a/src/blenderbim/blenderbim/bim/module/style/operator.py b/src/blenderbim/blenderbim/bim/module/style/operator.py
index cc7c2d6b81..fdd23e47e7 100644
--- a/src/blenderbim/blenderbim/bim/module/style/operator.py
+++ b/src/blenderbim/blenderbim/bim/module/style/operator.py
@@ -63,7 +63,7 @@ class UnlinkStyle(bpy.types.Operator, Operator):
     bl_options = {"REGISTER", "UNDO"}
 
     def _execute(self, context):
-        core.unlink_style(tool.Style, obj=context.active_object.active_material)
+        core.unlink_style(tool.Ifc, tool.Style, obj=context.active_object.active_material)
 
 
 class EnableEditingStyle(bpy.types.Operator, Operator):
diff --git a/src/blenderbim/blenderbim/core/style.py b/src/blenderbim/blenderbim/core/style.py
index 6369034106..0cc161c0be 100644
--- a/src/blenderbim/blenderbim/core/style.py
+++ b/src/blenderbim/blenderbim/core/style.py
@@ -19,7 +19,7 @@
 
 def add_style(ifc, style, obj=None):
     element = ifc.run("style.add_style", name=style.get_name(obj))
-    style.link(element, obj)
+    ifc.link(element, obj)
     ifc.run(
         "style.add_surface_style",
         style=element,
@@ -33,8 +33,9 @@ def add_style(ifc, style, obj=None):
 
 
 def remove_style(ifc, style, obj=None):
-    ifc.run("style.remove_style", style=style.get_style(obj))
-    style.unlink(obj=obj)
+    element = style.get_style(obj)
+    ifc.unlink(obj=obj, element=element)
+    ifc.run("style.remove_style", style=element)
 
 
 def update_style_colours(ifc, style, obj=None):
@@ -50,8 +51,8 @@ def update_style_colours(ifc, style, obj=None):
         ifc.run("style.edit_surface_style", style=shading_style, attributes=attributes)
 
 
-def unlink_style(style, obj=None):
-    style.unlink(obj)
+def unlink_style(ifc, style, obj=None):
+    ifc.unlink(obj=obj, element=style.get_style(obj))
 
 
 def enable_editing_style(style, obj=None):
diff --git a/src/blenderbim/blenderbim/core/tool.py b/src/blenderbim/blenderbim/core/tool.py
index b4f3fadb8c..41901ebde4 100644
--- a/src/blenderbim/blenderbim/core/tool.py
+++ b/src/blenderbim/blenderbim/core/tool.py
@@ -226,8 +226,6 @@ class Style:
     def get_surface_shading_attributes(cls, obj): pass
     def get_surface_shading_style(cls, obj): pass
     def import_surface_attributes(cls, style, obj): pass
-    def link(cls, style, obj): pass
-    def unlink(cls, obj): pass
 
 
 @interface
diff --git a/src/blenderbim/blenderbim/tool/geometry.py b/src/blenderbim/blenderbim/tool/geometry.py
index b39dd5900b..b56f09bfb7 100644
--- a/src/blenderbim/blenderbim/tool/geometry.py
+++ b/src/blenderbim/blenderbim/tool/geometry.py
@@ -36,7 +36,9 @@ class Geometry(blenderbim.core.tool.Geometry):
 
     @classmethod
     def clear_cache(cls, element):
-        IfcStore.get_cache().remove(element.GlobalId)
+        cache = IfcStore.get_cache()
+        if cache:
+            cache.remove(element.GlobalId)
 
     @classmethod
     def clear_modifiers(cls, obj):
@@ -224,7 +226,7 @@ class Geometry(blenderbim.core.tool.Geometry):
     def replace_object_with_empty(cls, obj):
         element = tool.Ifc.get_entity(obj)
         name = obj.name
-        tool.Ifc.unlink(obj)
+        tool.Ifc.unlink(obj=obj, element=element)
         obj.name = ifcopenshell.guid.new()
         new_obj = bpy.data.objects.new(name, None)
         if element:
diff --git a/src/blenderbim/blenderbim/tool/style.py b/src/blenderbim/blenderbim/tool/style.py
index 116b121654..a0d3e5cbf8 100644
--- a/src/blenderbim/blenderbim/tool/style.py
+++ b/src/blenderbim/blenderbim/tool/style.py
@@ -108,11 +108,3 @@ class Style(blenderbim.core.tool.Style):
     def import_surface_attributes(cls, style, obj):
         obj.BIMStyleProperties.attributes.clear()
         blenderbim.bim.helper.import_attributes2(style, obj.BIMStyleProperties.attributes)
-
-    @classmethod
-    def link(cls, style, obj):
-        obj.BIMMaterialProperties.ifc_style_id = style.id()
-
-    @classmethod
-    def unlink(self, obj):
-        obj.BIMMaterialProperties.ifc_style_id = 0
diff --git a/src/blenderbim/test/bim/feature/project.feature b/src/blenderbim/test/bim/feature/project.feature
index ef76a7e0ac..508fdd92ea 100644
--- a/src/blenderbim/test/bim/feature/project.feature
+++ b/src/blenderbim/test/bim/feature/project.feature
@@ -387,3 +387,17 @@ Scenario: Export IFC - with changed object scale synchronised
     And an empty Blender session is started
     And I press "bim.load_project(filepath='{cwd}/test/files/export.ifc')"
     Then the object "IfcWall/Cube" dimensions are "4,4,4"
+
+Scenario: Export IFC - with changed style colour synchronised
+    Given an empty IFC project
+    And I add a cube
+    And the object "Cube" is selected
+    And I add a material
+    And I set "scene.BIMRootProperties.ifc_class" to "IfcWall"
+    And I press "bim.assign_class"
+    And the object "IfcWall/Cube" is selected
+    When the material "Material" colour is set to "1,0,0,1"
+    And I press "export_ifc.bim(filepath='{cwd}/test/files/export.ifc')"
+    And an empty Blender session is started
+    And I press "bim.load_project(filepath='{cwd}/test/files/export.ifc')"
+    Then the material "Material" colour is "1,0,0,1"
diff --git a/src/blenderbim/test/bim/test_feature.py b/src/blenderbim/test/bim/test_feature.py
index 254a7c14c9..251640514e 100644
--- a/src/blenderbim/test/bim/test_feature.py
+++ b/src/blenderbim/test/bim/test_feature.py
@@ -95,6 +95,14 @@ def i_add_a_material():
     bpy.context.active_object.active_material = bpy.data.materials.new("Material")
 
 
+@given(parsers.parse('the material "{name}" colour is set to "{colour}"'))
+@when(parsers.parse('the material "{name}" colour is set to "{colour}"'))
+def the_material_name_colour_is_set_to_colour(name, colour):
+    obj = the_material_name_exists(name)
+    obj.diffuse_color = [float(c) for c in colour.split(",")]
+    blenderbim.bim.handler.color_callback(obj, None)
+
+
 @given("I add an array modifier")
 def i_add_a_cube():
     bpy.ops.object.modifier_add(type="ARRAY")
@@ -385,6 +393,12 @@ def the_material_name_is_not_an_ifc_material(name):
     assert id == 0, f"The ID is {id}"
 
 
+@then(parsers.parse('the material "{name}" colour is "{colour}"'))
+def the_material_name_colour_is_set_to_colour(name, colour):
+    diffuse_color = list(the_material_name_exists(name).diffuse_color)
+    assert diffuse_color == [float(c) for c in colour.split(",")], f"The colour is {diffuse_color}"
+
+
 @then(parsers.parse('the object "{name}" has "{number}" vertices'))
 def the_object_name_has_number_vertices(name, number):
     total = len(the_object_name_exists(name).data.vertices)
diff --git a/src/blenderbim/test/core/test_style.py b/src/blenderbim/test/core/test_style.py
index 298434335c..64dc5adea8 100644
--- a/src/blenderbim/test/core/test_style.py
+++ b/src/blenderbim/test/core/test_style.py
@@ -24,7 +24,7 @@ class TestAddStyle:
     def predict(self, ifc, style, obj="obj"):
         style.get_name(obj).should_be_called().will_return("name")
         ifc.run("style.add_style", name="name").should_be_called().will_return("style")
-        style.link("style", obj).should_be_called()
+        ifc.link("style", obj).should_be_called()
         style.get_surface_rendering_attributes(obj).should_be_called().will_return("attributes")
         ifc.run(
             "style.add_surface_style", style="style", ifc_class="IfcSurfaceStyleRendering", attributes="attributes"
@@ -38,7 +38,7 @@ class TestAddStyle:
     def test_adding_a_style_linked_to_a_material(self, ifc, style):
         style.get_name("obj").should_be_called().will_return("name")
         ifc.run("style.add_style", name="name").should_be_called().will_return("style")
-        style.link("style", "obj").should_be_called()
+        ifc.link("style", "obj").should_be_called()
         style.get_surface_rendering_attributes("obj").should_be_called().will_return("attributes")
         ifc.run(
             "style.add_surface_style", style="style", ifc_class="IfcSurfaceStyleRendering", attributes="attributes"
@@ -52,8 +52,8 @@ class TestAddStyle:
 class TestRemoveStyle:
     def test_run(self, ifc, style):
         style.get_style("obj").should_be_called().will_return("style")
+        ifc.unlink(obj="obj", element="style").should_be_called()
         ifc.run("style.remove_style", style="style").should_be_called()
-        style.unlink(obj="obj").should_be_called()
         subject.remove_style(ifc, style, obj="obj")
 
 
@@ -73,9 +73,10 @@ class TestUpdateStyleColours:
 
 
 class TestUnlinkStyle:
-    def test_run(self, style):
-        style.unlink("obj").should_be_called()
-        subject.unlink_style(style, obj="obj")
+    def test_run(self, ifc, style):
+        style.get_style("obj").should_be_called().will_return("style")
+        ifc.unlink(obj="obj", element="style").should_be_called()
+        subject.unlink_style(ifc, style, obj="obj")
 
 
 class TestEnableEditingStyle:
diff --git a/src/blenderbim/test/tool/test_ifc.py b/src/blenderbim/test/tool/test_ifc.py
index fa805371a0..0501618bec 100644
--- a/src/blenderbim/test/tool/test_ifc.py
+++ b/src/blenderbim/test/tool/test_ifc.py
@@ -119,6 +119,26 @@ class TestLink(test.bim.bootstrap.NewFile):
         assert subject.get_entity(obj) == element
         assert subject.get_object(element) == obj
 
+    def test_link_a_style(self):
+        ifc = ifcopenshell.file()
+        subject.set(ifc)
+        element = ifc.createIfcSurfaceStyle()
+        obj = bpy.data.materials.new("Material")
+        subject.link(element, obj)
+        assert subject.get_object(element) == obj
+
+    def test_link_a_material_and_style(self):
+        ifc = ifcopenshell.file()
+        subject.set(ifc)
+        style = ifc.createIfcSurfaceStyle()
+        material = ifc.createIfcMaterial()
+        obj = bpy.data.materials.new("Material")
+        subject.link(style, obj)
+        subject.link(material, obj)
+        assert subject.get_entity(obj) == material
+        assert subject.get_object(style) == obj
+        assert subject.get_object(material) == obj
+
 
 class TestUnlink(test.bim.bootstrap.NewFile):
     def test_unlink_an_object(self):
@@ -141,6 +161,31 @@ class TestUnlink(test.bim.bootstrap.NewFile):
         assert subject.get_entity(obj) is None
         assert subject.get_object(element) is None
 
+    def test_unlink_a_style(self):
+        ifc = ifcopenshell.file()
+        subject.set(ifc)
+        element = ifc.createIfcSurfaceStyle()
+        obj = bpy.data.materials.new("Material")
+        subject.link(element, obj)
+        subject.unlink(element, obj)
+        assert subject.get_object(element) is None
+
+    def test_unlink_a_style_and_material(self):
+        ifc = ifcopenshell.file()
+        subject.set(ifc)
+        style = ifc.createIfcSurfaceStyle()
+        material = ifc.createIfcMaterial()
+        obj = bpy.data.materials.new("Material")
+        subject.link(style, obj)
+        subject.link(material, obj)
+        subject.unlink(element=style, obj=obj)
+        assert subject.get_entity(obj) == material
+        assert subject.get_object(material) == obj
+        assert subject.get_object(style) is None
+        subject.unlink(element=material, obj=obj)
+        assert subject.get_entity(obj) is None
+        assert subject.get_object(material) is None
+
     def test_unlinking_using_an_object(self):
         ifc = ifcopenshell.file()
         subject.set(ifc)
diff --git a/src/blenderbim/test/tool/test_style.py b/src/blenderbim/test/tool/test_style.py
index 6071d49e2e..d297eb9abe 100644
--- a/src/blenderbim/test/tool/test_style.py
+++ b/src/blenderbim/test/tool/test_style.py
@@ -189,22 +189,3 @@ class TestImportSurfaceAttributes(NewFile):
         assert len(obj.BIMStyleProperties.attributes) == 2
         assert obj.BIMStyleProperties.attributes.get("Name").string_value == "Name"
         assert obj.BIMStyleProperties.attributes.get("Side").enum_value == "BOTH"
-
-
-class TestLink(NewFile):
-    def test_run(self):
-        obj = bpy.data.materials.new("Material")
-        ifc = ifcopenshell.file()
-        style = ifc.createIfcSurfaceStyle()
-        subject.link(style, obj)
-        assert obj.BIMMaterialProperties.ifc_style_id == style.id()
-
-
-class TestUnlink(NewFile):
-    def test_run(self):
-        obj = bpy.data.materials.new("Material")
-        ifc = ifcopenshell.file()
-        style = ifc.createIfcSurfaceStyle()
-        subject.link(style, obj)
-        subject.unlink(obj)
-        assert obj.BIMMaterialProperties.ifc_style_id == 0