diff --git a/src/blenderbim/blenderbim/bim/helper.py b/src/blenderbim/blenderbim/bim/helper.py
index 06508b50fa..45661d64f1 100644
--- a/src/blenderbim/blenderbim/bim/helper.py
+++ b/src/blenderbim/blenderbim/bim/helper.py
@@ -118,6 +118,17 @@ def prop_with_search(layout, data, prop_name, **kwargs):
     op.prop_name = prop_name
 
 
+def layout_with_margins(layout, margin_left=0.025, margin_right=None):
+    margin_right = margin_left if margin_right is None else margin_right
+    split = layout.split(factor=margin_left, align=True)
+    cols = [split.column() for _ in range(2)]
+    cols[0].label(text="")
+    subsplit = cols[-1].split(factor=(1. - margin_right), align=True)
+    subcol = subsplit.column()
+    subsplit.column().label(text="")
+    return subcol
+
+
 def get_enum_items(data, prop_name, context):
     # Retrieve items from a dynamic EnumProperty, which is otherwise not supported
     # Or throws an error in the console when the items callback returns an empty list
diff --git a/src/blenderbim/blenderbim/bim/module/model/__init__.py b/src/blenderbim/blenderbim/bim/module/model/__init__.py
index c226210dae..30c5ff8c12 100644
--- a/src/blenderbim/blenderbim/bim/module/model/__init__.py
+++ b/src/blenderbim/blenderbim/bim/module/model/__init__.py
@@ -17,11 +17,14 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
 
 import bpy
-from . import handler, prop, ui, grid, product, wall, slab, stair, opening, pie, workspace
+from . import handler, prop, ui, grid, product, wall, slab, stair, opening, pie, workspace, profile
 
 classes = (
     product.AddEmptyType,
-    product.AddTypeInstance,
+    product.AddConstrTypeInstance,
+    product.DisplayConstrTypes,
+    product.SelectConstructionType,
+    product.HelpConstrTypes,
     product.AlignProduct,
     product.DynamicallyVoidProduct,
     workspace.Hotkey,
@@ -32,8 +35,8 @@ classes = (
     opening.AddElementOpening,
     profile.ExtendProfile,
     prop.BIMModelProperties,
+    prop.ConstrTypeInfo,
     ui.BIM_PT_authoring,
-    ui.BIM_PT_authoring_architectural,
     grid.BIM_OT_add_object,
     stair.BIM_OT_add_object,
     opening.BIM_OT_add_object,
@@ -51,6 +54,7 @@ def register():
     if not bpy.app.background:
         bpy.utils.register_tool(workspace.BimTool, after={"builtin.scale_cage"}, separator=True, group=True)
     bpy.types.Scene.BIMModelProperties = bpy.props.PointerProperty(type=prop.BIMModelProperties)
+    bpy.types.Scene.ConstrTypeInfo = bpy.props.CollectionProperty(type=prop.ConstrTypeInfo)
     bpy.types.VIEW3D_MT_mesh_add.append(grid.add_object_button)
     bpy.types.VIEW3D_MT_mesh_add.append(stair.add_object_button)
     bpy.types.VIEW3D_MT_mesh_add.append(opening.add_object_button)
@@ -68,6 +72,7 @@ def unregister():
     if not bpy.app.background:
         bpy.utils.unregister_tool(workspace.BimTool)
     del bpy.types.Scene.BIMModelProperties
+    del bpy.types.Scene.ConstrTypeInfo
     bpy.app.handlers.load_post.remove(handler.load_post)
     bpy.types.VIEW3D_MT_mesh_add.remove(grid.add_object_button)
     bpy.types.VIEW3D_MT_mesh_add.remove(stair.add_object_button)
diff --git a/src/blenderbim/blenderbim/bim/module/model/data.py b/src/blenderbim/blenderbim/bim/module/model/data.py
index 393fe73273..c5ba73182c 100644
--- a/src/blenderbim/blenderbim/bim/module/model/data.py
+++ b/src/blenderbim/blenderbim/bim/module/model/data.py
@@ -16,8 +16,14 @@
 # You should have received a copy of the GNU General Public License
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
 
+import functools
 import bpy
 import blenderbim.tool as tool
+from blenderbim.bim.ifc import IfcStore
+
+
+preview_icon_ids = {}
+attempts = 0
 
 
 def refresh():
@@ -31,10 +37,29 @@ class AuthoringData:
     @classmethod
     def load(cls):
         cls.is_loaded = True
-        cls.data = {
-            "ifc_classes": cls.ifc_classes(),
-            "relating_types": cls.relating_types(),
-        }
+        if not hasattr(cls, "data"):
+            cls.data = {}
+        cls.props = bpy.context.scene.BIMModelProperties
+        cls.load_ifc_classes()
+        cls.load_relating_types()
+        cls.load_relating_types_browser()
+        cls.load_preview_constr_types()
+
+    @classmethod
+    def load_ifc_classes(cls):
+        cls.data["ifc_classes"] = cls.ifc_classes()
+
+    @classmethod
+    def load_relating_types(cls):
+        cls.data["relating_types_ids"] = cls.relating_types()
+
+    @classmethod
+    def load_relating_types_browser(cls):
+        cls.data["relating_types_ids_browser"] = cls.relating_types_browser()
+
+    @classmethod
+    def load_preview_constr_types(cls):
+        cls.data["preview_constr_types"] = preview_icon_ids
 
     @classmethod
     def ifc_classes(cls):
@@ -49,16 +74,131 @@ class AuthoringData:
         return results
 
     @classmethod
-    def relating_types(cls):
-        ifc_classes = cls.ifc_classes()
+    def constr_class_entities(cls, ifc_class=None):
+        ifc_classes = cls.data["ifc_classes"]
         if not ifc_classes:
             return []
         results = []
-        ifc_class = bpy.context.scene.BIMModelProperties.ifc_class
+        if ifc_class is None:
+            ifc_class = cls.props.ifc_class
         if not ifc_class and ifc_classes:
             ifc_class = ifc_classes[0][0]
         if ifc_class:
-            elements = [(str(e.id()), e.Name, e.Description or "") for e in tool.Ifc.get().by_type(ifc_class)]
-            results.extend(sorted(elements, key=lambda s: s[1]))
+            elements = sorted(tool.Ifc.get().by_type(ifc_class), key=lambda s: s.Name)
+            results.extend(elements)
             return results
         return []
+
+    @classmethod
+    def relating_types(cls, ifc_class=None):
+        return [
+            (str(e.id()), e.Name, e.Description or "") for e in cls.constr_class_entities(ifc_class=ifc_class)
+        ]
+
+    @classmethod
+    def relating_types_browser(cls):
+        return cls.relating_types(ifc_class=cls.props.ifc_class_browser)
+
+    @staticmethod
+    def new_relating_type_info(ifc_class):
+        relating_type_info = bpy.context.scene.ConstrTypeInfo.add()
+        relating_type_info.name = ifc_class
+        return relating_type_info
+
+    @classmethod
+    def assetize_constr_class(cls, ifc_class=None):
+        if ifc_class is None:
+            ifc_class = cls.props.ifc_class
+        relating_type_info = cls.relating_type_info(ifc_class)
+        _ = cls.new_relating_type_info(ifc_class) if relating_type_info is None else relating_type_info
+        constr_class_occurrences = cls.constr_class_entities(ifc_class)
+        preview_constr_types = cls.data["preview_constr_types"]
+        for constr_class_entity in constr_class_occurrences:
+
+            ### handle asset regeneration when library entity is updated ¿?
+            if (ifc_class not in preview_constr_types
+                    or str(constr_class_entity.id()) not in preview_constr_types[ifc_class]):
+                obj = tool.Ifc.get_object(constr_class_entity)
+                cls.assetize_object(obj, ifc_class, constr_class_entity)
+        relating_type_info = cls.relating_type_info(ifc_class)
+        relating_type_info.fully_loaded = True
+
+    @classmethod
+    def assetize_object(cls, obj, ifc_class, ifc_class_entity, from_selection=False):
+        relating_type_id = ifc_class_entity.id()
+        to_be_deleted = False
+        if obj.type == 'EMPTY':
+            kwargs = {}
+            if not from_selection:
+                kwargs.update({'ifc_class': ifc_class, 'relating_type_id': relating_type_id})
+            new_obj = cls.new_relating_type(**kwargs)
+            if new_obj is not None:
+                to_be_deleted = True
+                obj = new_obj
+        obj.asset_mark()
+        obj.asset_generate_preview()
+        icon_id = obj.preview.icon_id
+        if ifc_class not in cls.data["preview_constr_types"]:
+            cls.data["preview_constr_types"][ifc_class] = {}
+        cls.data["preview_constr_types"][ifc_class][str(relating_type_id)] = {"icon_id": icon_id, "object": obj}
+        if to_be_deleted:
+            for col in obj.users_collection:
+                col.objects.unlink(obj)
+
+    @classmethod
+    def assetize_relating_type_from_selection(cls):
+        ifc_class_browser = cls.props.ifc_class_browser
+        relating_type_id_browser = cls.props.relating_type_id_browser
+        constr_class_occurrences = cls.constr_class_entities(ifc_class=ifc_class_browser)
+        constr_class_occurrences = [
+            entity for entity in constr_class_occurrences if entity.id() == int(relating_type_id_browser)
+        ]
+        if len(constr_class_occurrences) == 0:
+            return False
+        constr_class_entity = constr_class_occurrences[0]
+        obj = tool.Ifc.get_object(constr_class_entity)
+        if obj is None:
+            return False
+        cls.assetize_object(obj, ifc_class_browser, constr_class_entity, from_selection=True)
+        return True
+
+    @staticmethod
+    def relating_type_info(ifc_class):
+        relating_type_infos = [element for element in bpy.context.scene.ConstrTypeInfo if element.name == ifc_class]
+        return None if len(relating_type_infos) == 0 else relating_type_infos[0]
+
+    @classmethod
+    def new_relating_type(cls, ifc_class=None, relating_type_id=None):
+        if ifc_class is None:
+            bpy.ops.bim.add_constr_type_instance(
+                ifc_class=cls.props.ifc_class_browser, relating_type_id=int(cls.props.relating_type_id_browser)
+            )
+        else:
+            cls.props.ifc_class = ifc_class
+            cls.props.relating_type_id = str(relating_type_id)
+            bpy.ops.bim.add_constr_type_instance()
+        return bpy.context.selected_objects[-1]
+
+    @staticmethod
+    def relating_type_name_by_id(ifc_class, relating_type_id):
+        file = IfcStore.get_file()
+        try:
+            constr_class_entity = file.by_id(int(relating_type_id))
+        except (RuntimeError, ValueError):
+            return None
+        return constr_class_entity.Name if constr_class_entity.is_a() == ifc_class else None
+
+    @classmethod
+    def relating_type_id_by_name(cls, ifc_class, relating_type):
+        relating_types = [ct[0] for ct in cls.relating_types(ifc_class=ifc_class) if ct[1] == relating_type]
+        return None if len(relating_types) == 0 else relating_types[0]
+
+    @classmethod
+    def consolidate_relating_type(cls):
+        cls.props.ifc_class = cls.props.ifc_class_browser
+        cls.props.relating_type_id = cls.props.relating_type_id_browser
+
+    @classmethod
+    def setup_relating_type_browser(cls):
+        cls.props.ifc_class_browser = cls.props.ifc_class
+        cls.props.relating_type_id_browser = cls.props.relating_type_id
diff --git a/src/blenderbim/blenderbim/bim/module/model/mep.py b/src/blenderbim/blenderbim/bim/module/model/mep.py
index e8b02b97e6..eeeaff9aee 100644
--- a/src/blenderbim/blenderbim/bim/module/model/mep.py
+++ b/src/blenderbim/blenderbim/bim/module/model/mep.py
@@ -114,5 +114,13 @@ class MepGenerator:
             tool.Ifc.run("system.assign_port", element=element, port=port)
             tool.Ifc.run("geometry.edit_object_placement", product=port, matrix=obj.matrix_world @ mat, is_si=True)
 
-        obj.select_set(True)
+        try:
+            obj.select_set(True)
+        except RuntimeError:
+            def msg(self, context):
+                txt = "The created object could not be assigned to a collection. "
+                txt += "Has any IfcSpatialElement been deleted?"
+                self.layout.label(text=txt)
+
+            bpy.context.window_manager.popup_menu(msg, title="Error", icon="ERROR")
         return obj
diff --git a/src/blenderbim/blenderbim/bim/module/model/product.py b/src/blenderbim/blenderbim/bim/module/model/product.py
index 20c948d4e3..312caa0dcf 100644
--- a/src/blenderbim/blenderbim/bim/module/model/product.py
+++ b/src/blenderbim/blenderbim/bim/module/model/product.py
@@ -17,6 +17,7 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
 
 import bpy
+import math
 import mathutils
 import ifcopenshell
 import ifcopenshell.api
@@ -29,9 +30,12 @@ import blenderbim.core.type
 import blenderbim.core.geometry
 from . import wall, slab, profile, mep
 from blenderbim.bim.ifc import IfcStore
+from blenderbim.bim.module.model.data import AuthoringData
+from blenderbim.bim.helper import prop_with_search, layout_with_margins, close_operator_panel
 from ifcopenshell.api.pset.data import Data as PsetData
 from mathutils import Vector, Matrix
 from bpy_extras.object_utils import AddObjectHelper
+from . import prop
 
 
 class AddEmptyType(bpy.types.Operator, AddObjectHelper):
@@ -53,13 +57,19 @@ def add_empty_type_button(self, context):
     self.layout.operator(AddEmptyType.bl_idname, icon="FILE_3D")
 
 
-class AddTypeInstance(bpy.types.Operator):
-    bl_idname = "bim.add_type_instance"
-    bl_label = "Add Type Instance"
+class AddConstrTypeInstance(bpy.types.Operator):
+    bl_idname = "bim.add_constr_type_instance"
+    bl_label = "Add"
     bl_options = {"REGISTER", "UNDO"}
-    bl_description = "Add the selected Type Instance to the model"
+    bl_description = "Add Type Instance to the model"
     ifc_class: bpy.props.StringProperty()
-    relating_type: bpy.props.IntProperty()
+    relating_type_id: bpy.props.IntProperty()
+    from_invoke: bpy.props.BoolProperty(default=False)
+
+    def invoke(self, context, event):
+        if self.from_invoke:
+            close_operator_panel(event)
+        return self.execute(context)
 
     def execute(self, context):
         return IfcStore.execute_ifc_operator(self, context)
@@ -67,11 +77,15 @@ class AddTypeInstance(bpy.types.Operator):
     def _execute(self, context):
         props = context.scene.BIMModelProperties
         ifc_class = self.ifc_class or props.ifc_class
-        relating_type_id = self.relating_type or props.relating_type
+        relating_type_id = self.relating_type_id or props.relating_type_id
 
         if not ifc_class or not relating_type_id:
             return {"FINISHED"}
 
+        if self.from_invoke:
+            props.ifc_class = self.ifc_class
+            props.relating_type_id = str(self.relating_type_id)
+
         self.file = IfcStore.get_file()
         instance_class = ifcopenshell.util.type.get_applicable_entities(ifc_class, self.file.schema)[0]
         relating_type = self.file.by_id(int(relating_type_id))
@@ -150,7 +164,8 @@ class AddTypeInstance(bpy.types.Operator):
         context.view_layer.objects.active = obj
         return {"FINISHED"}
 
-    def generate_layered_element(self, ifc_class, relating_type):
+    @staticmethod
+    def generate_layered_element(ifc_class, relating_type):
         layer_set_direction = None
 
         parametric = ifcopenshell.util.element.get_psets(relating_type).get("EPset_Parametric")
@@ -172,6 +187,217 @@ class AddTypeInstance(bpy.types.Operator):
             pass  # Dumb block generator? Eh? :)
 
 
+class DisplayConstrTypes(bpy.types.Operator):
+    bl_idname = "bim.display_relating_types"
+    bl_label = "Browse Construction Types"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_description = "Display all available Construction Types to add new instances"
+
+    def execute(self, context):
+        return {"FINISHED"}
+
+    def invoke(self, context, event):
+        if not AuthoringData.is_loaded:
+            AuthoringData.load()
+        AuthoringData.setup_relating_type_browser()
+        props = context.scene.BIMModelProperties
+        if props.unfold_relating_types:
+            ifc_class = props.ifc_class_browser
+            relating_type_info = AuthoringData.relating_type_info(ifc_class)
+            if relating_type_info is None or not relating_type_info.fully_loaded:
+                AuthoringData.assetize_constr_class(ifc_class)
+        else:
+            prop.update_relating_type_browser(props, context)
+        min_width = 250
+        width_scaling = 5 ** -1
+        width = max([min_width, int(width_scaling * context.region.width)])
+        return context.window_manager.invoke_popup(self, width=width)
+
+    def draw(self, context):
+        props = context.scene.BIMModelProperties
+        header_data = self.draw_header(props)
+        if props.unfold_relating_types:
+            self.draw_by_ifc_class(props, header_data)
+        else:
+            self.draw_by_ifc_class_and_type(props, header_data)
+
+    def draw_header(self, props):
+        layout = self.layout
+        inner_layout = layout_with_margins(layout, margin_left=0.004)
+        inner_layout.row().separator(factor=0.75)
+        split = inner_layout.split(align=True, factor=2./3)
+        col1 = split.column(align=True)
+        row = col1.row()
+        row.prop(data=props, property="unfold_relating_types", text="Preview All Construction Types")
+        col1.row().separator(factor=1)
+        row = col1.row()
+        row.label(text="Select Construction Type:")
+        col1.row().separator(factor=1.5)
+        enabled = True
+        if AuthoringData.data["ifc_classes"]:
+            subsplit = col1.split(factor=1./3)
+            subsplit.column().row().label(text="Construction Class:", icon="FILE_VOLUME")
+            prop_with_search(subsplit.column(), props, "ifc_class_browser", text="")
+            col1.row().separator()
+        else:
+            enabled = False
+        col2 = split.column(align=True)
+        subsplit = col2.split(factor=0.9)
+        subcol = [subsplit.column() for _ in range(2)][-1]
+        subcol.operator("bim.help_relating_types", text="", icon="QUESTION")
+        col2.row().separator(factor=1)
+        return {"enabled": enabled, "layout": inner_layout, "col1": col1, "col2": col2}
+
+    def draw_by_ifc_class(self, props, header_data):
+        enabled, layout = [header_data[key] for key in ["enabled", "layout"]]
+        ifc_class_browser = props.ifc_class_browser
+        num_cols = 3
+        layout.row().separator(factor=0.25)
+        layout.row().label(text="Construction Types:", icon="FILE_3D")
+        layout.row().separator(factor=0.25)
+        flow = layout.grid_flow(row_major=True, columns=num_cols, even_columns=True, even_rows=True, align=True)
+        relating_types_browser = AuthoringData.relating_types_browser()
+        num_types = len(relating_types_browser)
+        for idx, (relating_type_id_browser, name, desc) in enumerate(relating_types_browser):
+            outer_col = flow.column()
+            box = outer_col.box()
+            row = box.row()
+            row.label(text=name, icon="FILE_3D")
+            row.alignment = "CENTER"
+            row = box.row()
+            if enabled:
+                preview_constr_types = AuthoringData.data["preview_constr_types"]
+                if ifc_class_browser in preview_constr_types:
+                    preview_ifc_class = preview_constr_types[ifc_class_browser]
+                    if relating_type_id_browser in preview_ifc_class:
+                        icon_id = preview_ifc_class[relating_type_id_browser]["icon_id"]
+                        row.template_icon(icon_value=icon_id, scale=6.)
+            box.row().separator(factor=0.2)
+            row = box.row()
+            split = row.split(factor=0.5)
+            col = split.column()
+            op = col.operator("bim.select_construction_type", icon="RIGHTARROW_THIN")
+            op.ifc_class = ifc_class_browser
+            op.relating_type_id = relating_type_id_browser
+            col = split.column()
+            op = col.operator("bim.add_constr_type_instance", icon="ADD")
+            op.from_invoke = True
+            op.ifc_class = ifc_class_browser
+            if relating_type_id_browser.isnumeric():
+                op.relating_type_id = int(relating_type_id_browser)
+            factor = 2 if idx + 1 < math.ceil(num_types / num_cols) else 1.5
+            outer_col.row().separator(factor=factor)
+        last_row_cols = num_types % num_cols
+        if last_row_cols != 0:
+            for _ in range(num_cols - last_row_cols):
+                flow.column()
+
+    def draw_by_ifc_class_and_type(self, props, header_data):
+        enabled, col1, col2 = [header_data[key] for key in ["enabled", "col1", "col2"]]
+        ifc_class_browser = props.ifc_class_browser
+        relating_type_id_browser = props.relating_type_id_browser
+        if AuthoringData.data["relating_types_ids_browser"]:
+            subsplit = col1.split(factor=1. / 3)
+            subsplit.column().row().label(text="Construction Type:", icon="FILE_3D")
+            prop_with_search(subsplit.column(), props, "relating_type_id_browser", text="")
+            col1.row().separator()
+        else:
+            enabled = False
+        col1.row().separator(factor=4.75)
+        row = col1.row()
+        row.enabled = enabled
+        op = row.operator("bim.select_construction_type", icon="RIGHTARROW_THIN")
+        op.ifc_class = ifc_class_browser
+        op.relating_type_id = relating_type_id_browser
+        op = row.operator("bim.add_constr_type_instance", icon="ADD")
+        op.from_invoke = True
+        op.ifc_class = ifc_class_browser
+        if relating_type_id_browser.isnumeric():
+            op.relating_type_id = int(relating_type_id_browser)
+        col2.row().separator(factor=1.25)
+        split = col2.split(factor=0.025)
+        col = [split.column() for _ in range(2)][-1]
+        box = col.box()
+        if enabled:
+            box.template_icon(icon_value=props.icon_id, scale=5.6)
+        col1.row().separator(factor=1)
+
+
+class SelectConstructionType(bpy.types.Operator):
+    bl_idname = "bim.select_construction_type"
+    bl_label = "Select"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_description = "Pick Type Instance as selection for subsequent operations"
+    ifc_class: bpy.props.StringProperty()
+    relating_type_id: bpy.props.StringProperty()
+
+    def invoke(self, context, event):
+        close_operator_panel(event)
+        return self.execute(context)
+
+    def execute(self, context):
+        props = context.scene.BIMModelProperties
+        if self.ifc_class != "":
+            props.ifc_class = self.ifc_class
+            AuthoringData.load_relating_types()
+        if self.relating_type_id != "":
+            props.relating_type_id = self.relating_type_id
+        return {"FINISHED"}
+
+
+class HelpConstrTypes(bpy.types.Operator):
+    bl_idname = "bim.help_relating_types"
+    bl_label = "Construction Types Help"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_description = "Click to read some contextual help"
+
+    def execute(self, context):
+        return {"FINISHED"}
+
+    def invoke(self, context, event):
+        return context.window_manager.invoke_popup(self, width=510)
+
+    def draw(self, context):
+        layout = self.layout
+        layout.row().separator(factor=0.5)
+        row = layout.row()
+        row.alignment = "CENTER"
+        row.label(text="BlenderBIM Help", icon="BLENDER")
+        layout.row().separator(factor=0.5)
+
+        row = layout_with_margins(layout.row()).row()
+        row.label(text="Overview:", icon="KEYTYPE_MOVING_HOLD_VEC")
+        self.draw_lines(layout, self.message_summary)
+        layout.row().separator()
+
+        row = layout_with_margins(layout.row()).row()
+        row.label(text="Further support:", icon="KEYTYPE_MOVING_HOLD_VEC")
+        layout.row().separator(factor=0.5)
+        row = layout_with_margins(layout).row()
+        op = row.operator("bim.open_upstream", text="Homepage", icon="HOME")
+        op.page = "home"
+        op = row.operator("bim.open_upstream", text="Docs", icon="DOCUMENTS")
+        op.page = "docs"
+        op = row.operator("bim.open_upstream", text="Wiki", icon="CURRENT_FILE")
+        op.page = "wiki"
+        op = row.operator("bim.open_upstream", text="Community", icon="COMMUNITY")
+        op.page = "community"
+        layout.row().separator()
+
+    def draw_lines(self, layout, lines):
+        box = layout_with_margins(layout).box()
+        for line in lines:
+            row = box.row()
+            row.label(text=f"  {line}")
+
+    @property
+    def message_summary(self):
+        return [
+            'The Construction Type Browser allows to preview and add new instances to the model.',
+            'For further support, please click on the Documentation link below.'
+        ]
+
+
 class AlignProduct(bpy.types.Operator):
     bl_idname = "bim.align_product"
     bl_label = "Align Product"
diff --git a/src/blenderbim/blenderbim/bim/module/model/profile.py b/src/blenderbim/blenderbim/bim/module/model/profile.py
index 1c3e6bbe26..b074ef6dac 100644
--- a/src/blenderbim/blenderbim/bim/module/model/profile.py
+++ b/src/blenderbim/blenderbim/bim/module/model/profile.py
@@ -162,7 +162,15 @@ class DumbProfileGenerator:
         pset = ifcopenshell.api.run("pset.add_pset", self.file, product=element, name="EPset_Parametric")
         ifcopenshell.api.run("pset.edit_pset", self.file, pset=pset, properties={"Engine": "BlenderBIM.DumbProfile"})
         MaterialData.load(self.file)
-        obj.select_set(True)
+        try:
+            obj.select_set(True)
+        except RuntimeError:
+            def msg(self, context):
+                txt = "The created object could not be assigned to a collection. "
+                txt += "Has any IfcSpatialElement been deleted?"
+                self.layout.label(text=txt)
+
+            bpy.context.window_manager.popup_menu(msg, title="Error", icon="ERROR")
         return obj
 
 
diff --git a/src/blenderbim/blenderbim/bim/module/model/prop.py b/src/blenderbim/blenderbim/bim/module/model/prop.py
index 1cbe8eb3df..9d6b7b3794 100644
--- a/src/blenderbim/blenderbim/bim/module/model/prop.py
+++ b/src/blenderbim/blenderbim/bim/module/model/prop.py
@@ -17,21 +17,8 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
 
 import bpy
-import ifcopenshell.util.type
 from blenderbim.bim.module.model.data import AuthoringData
-from blenderbim.bim.prop import StrProperty, Attribute
-from blenderbim.bim.ifc import IfcStore
 from bpy.types import PropertyGroup
-from bpy.props import (
-    PointerProperty,
-    StringProperty,
-    EnumProperty,
-    BoolProperty,
-    IntProperty,
-    FloatProperty,
-    FloatVectorProperty,
-    CollectionProperty,
-)
 
 
 def get_ifc_class(self, context):
@@ -43,18 +30,110 @@ def get_ifc_class(self, context):
 def get_relating_type(self, context):
     if not AuthoringData.is_loaded:
         AuthoringData.load()
-    return AuthoringData.data["relating_types"]
+    return AuthoringData.data["relating_types_ids"]
+
+
+def get_relating_type_browser(self, context):
+    if not AuthoringData.is_loaded:
+        AuthoringData.load()
+    return AuthoringData.data["relating_types_ids_browser"]
+
+
+def update_icon_id(self, context):
+    ifc_class_browser = self.ifc_class_browser
+    relating_type_id_browser = self.relating_type_id_browser
+    relating_type_browser = AuthoringData.relating_type_name_by_id(ifc_class_browser, relating_type_id_browser)
+    if ((ifc_class_browser not in AuthoringData.data["preview_constr_types"]
+            or relating_type_id_browser not in AuthoringData.data["preview_constr_types"][ifc_class_browser])
+            and relating_type_browser is not None):
+        if not AuthoringData.assetize_relating_type_from_selection():
+            return
+    self.icon_id = AuthoringData.data["preview_constr_types"][ifc_class_browser][relating_type_id_browser]["icon_id"]
 
 
 def update_ifc_class(self, context):
-    AuthoringData.is_loaded = False
+    AuthoringData.load_ifc_classes()
+    AuthoringData.load_relating_types()
+    self.relating_type_id = AuthoringData.data["relating_types_ids"][0][0]
+
+
+def update_ifc_class_browser(self, context):
+    AuthoringData.load_ifc_classes()
+    AuthoringData.load_relating_types_browser()
+    props = context.scene.BIMModelProperties
+    if props.unfold_relating_types:
+        ifc_class_browser = props.ifc_class_browser
+        relating_type_info = AuthoringData.relating_type_info(ifc_class_browser)
+        if relating_type_info is None or not relating_type_info.fully_loaded:
+            curr_selection = props.ifc_class, props.relating_type_id
+            AuthoringData.assetize_constr_class(ifc_class_browser)
+            props.ifc_class, props.relating_type_id = curr_selection
+    else:
+        self.relating_type_id_browser = AuthoringData.data["relating_types_ids_browser"][0][0]
+
+
+def update_relating_type(self, context):
+    AuthoringData.load_relating_types()
+
+
+def update_relating_type_by_name(self, context):
+    AuthoringData.load_relating_types()
+    relating_type_id = AuthoringData.relating_type_id_by_name(self.ifc_class, self.relating_type)
+    if relating_type_id is not None:
+        self.relating_type_id = relating_type_id
+
+
+def update_relating_type_browser_by_name(self, context):
+    AuthoringData.load_relating_types_browser()
+    relating_type_id_browser = AuthoringData.relating_type_id_by_name(self.ifc_class_browser, self.relating_type_browser)
+    if relating_type_id_browser is not None:
+        self.relating_type_id_browser = relating_type_id_browser
+
+
+def update_relating_type_browser(self, context):
+    AuthoringData.load_relating_types_browser()
+    update_icon_id(self, context)
+
+
+def update_unfold_relating_type(self, context):
+    update_ifc_class_browser(self, context)
 
 
 class BIMModelProperties(PropertyGroup):
-    ifc_class: bpy.props.EnumProperty(items=get_ifc_class, name="IFC Class", update=update_ifc_class)
-    relating_type: bpy.props.EnumProperty(items=get_relating_type, name="Relating Type")
+    ifc_class: bpy.props.EnumProperty(items=get_ifc_class, name="Construction Class", update=update_ifc_class)
+    ifc_class_browser: bpy.props.EnumProperty(
+        items=get_ifc_class, name="Construction Class", update=update_ifc_class_browser
+    )
+    relating_type: bpy.props.StringProperty(update=update_relating_type_by_name)
+    relating_type_id: bpy.props.EnumProperty(
+        items=get_relating_type, name="Construction Type", update=update_relating_type
+    )
+    relating_type_browser: bpy.props.StringProperty(update=update_relating_type_browser_by_name)
+    relating_type_id_browser: bpy.props.EnumProperty(
+        items=get_relating_type_browser, name="Construction Type", update=update_relating_type_browser
+    )
+    icon_id: bpy.props.IntProperty()
+    unfold_relating_types: bpy.props.BoolProperty(update=update_unfold_relating_type)
     occurrence_name_style: bpy.props.EnumProperty(
         items=[("CLASS", "By Class", ""), ("TYPE", "By Type", ""), ("CUSTOM", "Custom", "")],
         name="Occurrence Name Style",
     )
     occurrence_name_function: bpy.props.StringProperty(name="Occurrence Name Function")
+    getter_enum = {
+        "ifc_class_browser": get_ifc_class,
+        "relating_type_browser": get_relating_type_browser
+    }
+
+
+def get_relating_type_info(self, context):
+    return AuthoringData.relating_types(ifc_class=self.name)
+
+
+class ConstrTypeInfo(PropertyGroup):
+    name: bpy.props.StringProperty(name="Construction class")
+    relating_type: bpy.props.EnumProperty(
+        name="Construction type", items=get_relating_type_info
+    )
+    fully_loaded: bpy.props.BoolProperty(default=False)
+
+
diff --git a/src/blenderbim/blenderbim/bim/module/model/slab.py b/src/blenderbim/blenderbim/bim/module/model/slab.py
index 622f447e83..6a96490d18 100644
--- a/src/blenderbim/blenderbim/bim/module/model/slab.py
+++ b/src/blenderbim/blenderbim/bim/module/model/slab.py
@@ -166,7 +166,7 @@ def calculate_quantities(usecase_path, ifc_file, settings):
     obj = settings["blender_object"]
     product = ifc_file.by_id(obj.BIMObjectProperties.ifc_definition_id)
     parametric = ifcopenshell.util.element.get_psets(product).get("EPset_Parametric")
-    if not parametric or parametric["Engine"] != "BlenderBIM.DumbLayer3":
+    if not parametric or "Engine" not in parametric or parametric["Engine"] != "BlenderBIM.DumbLayer3":
         return
     qto = ifcopenshell.api.run(
         "pset.add_qto", ifc_file, should_run_listeners=False, product=product, name="Qto_SlabBaseQuantities"
@@ -306,7 +306,15 @@ class DumbSlabGenerator:
         pset = ifcopenshell.api.run("pset.add_pset", self.file, product=element, name="EPset_Parametric")
         ifcopenshell.api.run("pset.edit_pset", self.file, pset=pset, properties={"Engine": "BlenderBIM.DumbLayer3"})
         MaterialData.load(self.file)
-        obj.select_set(True)
+        try:
+            obj.select_set(True)
+        except RuntimeError:
+            def msg(self, context):
+                txt = "The created object could not be assigned to a collection. "
+                txt += "Has any IfcSpatialElement been deleted?"
+                self.layout.label(text=txt)
+
+            bpy.context.window_manager.popup_menu(msg, title="Error", icon="ERROR")
         return obj
 
 
@@ -342,6 +350,23 @@ class DumbSlabPlaner:
             return
         new_thickness = sum([l.LayerThickness for l in new_material.MaterialLayers])
         material = ifcopenshell.util.element.get_material(settings["related_object"])
+
+        relating_type = settings["relating_type"]
+        if hasattr(relating_type, "HasPropertySets"):
+            psets = relating_type.HasPropertySets
+            if psets is not None:
+                for pset in psets:
+                    if hasattr(pset, "HasProperties"):
+                        pset_props = pset.HasProperties
+                        if pset_props is not None:
+                            for prop in pset_props:
+                                if prop.Name == "LayerSetDirection":
+                                    if hasattr(prop, "NominalValue"):
+                                        nominal_value = prop.NominalValue
+                                        if hasattr(nominal_value, "wrappedValue"):
+                                            if nominal_value.wrappedValue == "AXIS2":
+                                                return
+
         if material and material.is_a("IfcMaterialLayerSetUsage") and material.LayerSetDirection == "AXIS3":
             self.change_thickness(settings["related_object"], new_thickness)
 
diff --git a/src/blenderbim/blenderbim/bim/module/model/ui.py b/src/blenderbim/blenderbim/bim/module/model/ui.py
index 8a198ce7a1..dcdcf6655d 100644
--- a/src/blenderbim/blenderbim/bim/module/model/ui.py
+++ b/src/blenderbim/blenderbim/bim/module/model/ui.py
@@ -16,54 +16,15 @@
 # You should have received a copy of the GNU General Public License
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
 
-import blenderbim.bim.module.type.prop as type_prop
 from bpy.types import Panel
-from blenderbim.bim.ifc import IfcStore
-from blenderbim.bim.module.model.data import AuthoringData
 
 
 class BIM_PT_authoring(Panel):
-    bl_idname = "BIM_PT_authoring"
-    bl_label = "Authoring"
-    bl_space_type = "VIEW_3D"
-    bl_region_type = "UI"
-    bl_category = "BlenderBIM"
-
-    @classmethod
-    def poll(cls, context):
-        return IfcStore.get_file()
-
-    def draw(self, context):
-        if not AuthoringData.is_loaded:
-            AuthoringData.load()
-
-        props = context.scene.BIMModelProperties
-        col = self.layout.column(align=True)
-        enabled = True
-
-        if AuthoringData.data["ifc_classes"]:
-            col.prop(props, "ifc_class", text="", icon="FILE_VOLUME")
-        else:
-            col.label(text="No IFC Class", icon="FILE_VOLUME")
-            enabled = False
-        if AuthoringData.data["relating_types"]:
-            col.prop(props, "relating_type", text="", icon="FILE_3D")
-        else:
-            col.label(text="No Relating Type", icon="FILE_3D")
-            enabled = False
-        row = col.row()
-        row.operator("bim.add_type_instance", icon="ADD")
-        row.enabled = enabled
-
-
-class BIM_PT_authoring_architectural(Panel):
     bl_label = "Architectural"
-    bl_idname = "BIM_PT_authoring_architectural"
-    bl_options = {"DEFAULT_CLOSED"}
+    bl_idname = "BIM_PT_authoring"
     bl_space_type = "VIEW_3D"
     bl_region_type = "UI"
     bl_category = "BlenderBIM"
-    bl_parent_id = "BIM_PT_authoring"
 
     def draw(self, context):
         row = self.layout.row(align=True)
diff --git a/src/blenderbim/blenderbim/bim/module/model/wall.py b/src/blenderbim/blenderbim/bim/module/model/wall.py
index 368c907350..b3662208c1 100644
--- a/src/blenderbim/blenderbim/bim/module/model/wall.py
+++ b/src/blenderbim/blenderbim/bim/module/model/wall.py
@@ -817,7 +817,15 @@ class DumbWallGenerator:
         pset = ifcopenshell.api.run("pset.add_pset", self.file, product=element, name="EPset_Parametric")
         ifcopenshell.api.run("pset.edit_pset", self.file, pset=pset, properties={"Engine": "BlenderBIM.DumbLayer2"})
         MaterialData.load(self.file)
-        obj.select_set(True)
+        try:
+            obj.select_set(True)
+        except RuntimeError:
+            def msg(self, context):
+                txt = "The created object could not be assigned to a collection. "
+                txt += "Has any IfcSpatialElement been deleted?"
+                self.layout.label(text=txt)
+
+            bpy.context.window_manager.popup_menu(msg, title="Error", icon="ERROR")
         return obj
 
 
@@ -861,7 +869,7 @@ def calculate_quantities(usecase_path, ifc_file, settings):
     obj = settings["blender_object"]
     product = ifc_file.by_id(obj.BIMObjectProperties.ifc_definition_id)
     parametric = ifcopenshell.util.element.get_psets(product).get("EPset_Parametric")
-    if not parametric or parametric["Engine"] != "BlenderBIM.DumbLayer2":
+    if not parametric or "Engine" not in parametric or parametric["Engine"] != "BlenderBIM.DumbLayer2":
         return
     qto = ifcopenshell.api.run(
         "pset.add_qto", ifc_file, should_run_listeners=False, product=product, name="Qto_WallBaseQuantities"
@@ -941,6 +949,23 @@ class DumbWallPlaner:
             return
         new_thickness = sum([l.LayerThickness for l in new_material.MaterialLayers])
         material = ifcopenshell.util.element.get_material(settings["related_object"])
+
+        relating_type = settings["relating_type"]
+        if hasattr(relating_type, "HasPropertySets"):
+            psets = relating_type.HasPropertySets
+            if psets is not None:
+                for pset in psets:
+                    if hasattr(pset, "HasProperties"):
+                        pset_props = pset.HasProperties
+                        if pset_props is not None:
+                            for prop in pset_props:
+                                if prop.Name == "LayerSetDirection":
+                                    if hasattr(prop, "NominalValue"):
+                                        nominal_value = prop.NominalValue
+                                        if hasattr(nominal_value, "wrappedValue"):
+                                            if nominal_value.wrappedValue == "AXIS3":
+                                                return
+
         if material and material.is_a("IfcMaterialLayerSetUsage") and material.LayerSetDirection == "AXIS2":
             self.change_thickness(settings["related_object"], new_thickness)
 
diff --git a/src/blenderbim/blenderbim/bim/module/model/workspace.py b/src/blenderbim/blenderbim/bim/module/model/workspace.py
index 20239c2855..d7be1ebe61 100644
--- a/src/blenderbim/blenderbim/bim/module/model/workspace.py
+++ b/src/blenderbim/blenderbim/bim/module/model/workspace.py
@@ -55,28 +55,56 @@ class BimTool(WorkSpaceTool):
         if not AuthoringData.is_loaded and IfcStore.get_file():
             AuthoringData.load()
 
+        props = context.scene.BIMModelProperties
+        is_tool_header = context.region.type == "TOOL_HEADER"
         row = layout.row(align=True)
         if not IfcStore.get_file():
             row.label(text="No IFC Project", icon="ERROR")
             return
-        props = context.scene.BIMModelProperties
-        if AuthoringData.data["ifc_classes"]:
-            row.prop(props, "ifc_class", text="")
-        else:
-            row.label(text="No IFC Class")
-        if AuthoringData.data["relating_types"]:
-            row.prop(props, "relating_type", text="")
-        else:
-            row.label(text="No Relating Type")
 
-        row.label(text="", icon="BLANK1")
+        ifc_classes = AuthoringData.data["ifc_classes"]
+        relating_types_ids = AuthoringData.data["relating_types_ids"]
 
-        row = layout.row(align=True)
-        row.label(text="", icon="EVENT_SHIFT")
-        row.label(text="Add Type Instance", icon="EVENT_A")
+        if is_tool_header:
+            row.operator("bim.help_relating_types", text="", icon="QUESTION")
+
+        if ifc_classes and is_tool_header:
+            row.label(text="", icon="BLANK1")
+            row.operator("bim.display_relating_types", icon="COLLAPSEMENU")
+
+        ifc_class = props.ifc_class
+        relating_type_id = props.relating_type_id
+        relating_type = AuthoringData.relating_type_name_by_id(ifc_class, relating_type_id)
+
+        if is_tool_header:
+            row.label(text="", icon="BLANK1")
+            row = layout.row(align=True)
+            row.label(text="", icon="EVENT_SHIFT")
+            row.label(text="", icon="EVENT_A")
+            if ifc_classes:
+                row.label(text=f" Add")
+                row.label(text="", icon="FILE_VOLUME")
+                row.label(text=ifc_class)
+                row.label(text="", icon="FILE_3D")
+                row.label(text=f"{relating_type}  ")
+            else:
+                row.label(text=f" Add instance")
+        else:
+            txt_ifc_class = ifc_class if ifc_classes else "No Construction Class"
+            txt_relating_type = relating_type if relating_types_ids else "No Construction Type"
+            row = layout.row(align=True)
+            row.label(text="Selected Construction Type:")
+            row = layout.row(align=True)
+            row.label(text=txt_ifc_class, icon="FILE_VOLUME")
+            row = layout.row(align=True)
+            row.label(text=txt_relating_type, icon="FILE_3D")
+            row = layout.row(align=True)
+            row.label(text="", icon="EVENT_SHIFT")
+            row.label(text="", icon="EVENT_A")
+            row.label(text=f" Add Type Instance")
 
         if AuthoringData.data["ifc_classes"]:
-            if props.ifc_class == "IfcWallType":
+            if ifc_class == "IfcWallType":
                 row = layout.row()
                 row.label(text="Join")
                 row = layout.row(align=True)
@@ -98,7 +126,7 @@ class BimTool(WorkSpaceTool):
                 row.label(text="", icon="EVENT_SHIFT")
                 row.label(text="Split", icon="EVENT_S")
 
-            if props.ifc_class in ("IfcColumnType", "IfcBeamType", "IfcMemberType"):
+            if ifc_class in ("IfcColumnType", "IfcBeamType", "IfcMemberType"):
                 row = layout.row()
                 row.label(text="Join")
                 row = layout.row(align=True)
@@ -156,7 +184,7 @@ class Hotkey(bpy.types.Operator):
         return {"FINISHED"}
 
     def hotkey_S_A(self):
-        bpy.ops.bim.add_type_instance()
+        bpy.ops.bim.add_constr_type_instance()
 
     def hotkey_S_C(self):
         if self.has_ifc_class and self.props.ifc_class == "IfcWallType":
diff --git a/src/blenderbim/blenderbim/bim/module/type/ui.py b/src/blenderbim/blenderbim/bim/module/type/ui.py
index 95256e99c7..58cebe2c14 100644
--- a/src/blenderbim/blenderbim/bim/module/type/ui.py
+++ b/src/blenderbim/blenderbim/bim/module/type/ui.py
@@ -88,4 +88,4 @@ class BIM_PT_type(Panel):
 
 
 def add_object_button(self, context):
-    self.layout.operator("bim.add_type_instance", icon="PLUGIN")
+    self.layout.operator("bim.add_constr_type_instance", icon="PLUGIN")
diff --git a/src/blenderbim/blenderbim/tool/collector.py b/src/blenderbim/blenderbim/tool/collector.py
index e202ab50cb..8b08e14f0b 100644
--- a/src/blenderbim/blenderbim/tool/collector.py
+++ b/src/blenderbim/blenderbim/tool/collector.py
@@ -82,7 +82,8 @@ class Collector(blenderbim.core.tool.Collector):
         if obj.users_collection != (object_collection,):
             for collection in obj.users_collection:
                 collection.objects.unlink(obj)
-            object_collection.objects.link(obj)
+            if object_collection is not None:
+                object_collection.objects.link(obj)
 
         if collection_collection and collection_collection.children.find(object_collection.name) == -1:
             if bpy.context.scene.collection.children.find(object_collection.name) != -1:
diff --git a/src/blenderbim/test/bim/feature/geometry.feature b/src/blenderbim/test/bim/feature/geometry.feature
index dae44cff62..ee0cdedc39 100644
--- a/src/blenderbim/test/bim/feature/geometry.feature
+++ b/src/blenderbim/test/bim/feature/geometry.feature
@@ -31,8 +31,8 @@ Scenario: Add representation - add a new representation to a typed instance
     And I set "scene.BIMRootProperties.ifc_product" to "IfcElementType"
     And I set "scene.BIMRootProperties.ifc_class" to "IfcWallType"
     And I press "bim.assign_class"
-    And I press "bim.add_type_instance"
-    And I press "bim.add_type_instance"
+    And I press "bim.add_constr_type_instance"
+    And I press "bim.add_constr_type_instance"
     Then the object "IfcWall/Wall" data is a "Tessellation" representation of "Model/Body/MODEL_VIEW"
     And the object "IfcWall/Wall.001" data is a "Tessellation" representation of "Model/Body/MODEL_VIEW"
     When the object "IfcWall/Wall" is selected
@@ -146,9 +146,9 @@ Scenario: Remove representation - remove an instanced representation from an act
     And I press "bim.assign_class"
     And I set "scene.BIMModelProperties.ifc_class" to "IfcWallType"
     And the variable "cube" is "{ifc}.by_type('IfcWallType')[0].id()"
-    And I set "scene.BIMModelProperties.relating_type" to "{cube}"
-    And I press "bim.add_type_instance"
-    And I press "bim.add_type_instance"
+    And I set "scene.BIMModelProperties.relating_type_id" to "{cube}"
+    And I press "bim.add_constr_type_instance"
+    And I press "bim.add_constr_type_instance"
     And the object "IfcWallType/Cube" is selected
     When the variable "representation" is "{ifc}.by_type('IfcWallType')[0].RepresentationMaps[1].MappedRepresentation.id()"
     And I press "bim.remove_representation(representation_id={representation})"
@@ -165,9 +165,9 @@ Scenario: Remove representation - remove an instanced representation from an act
     And I press "bim.assign_class"
     And I set "scene.BIMModelProperties.ifc_class" to "IfcWallType"
     And the variable "cube" is "{ifc}.by_type('IfcWallType')[0].id()"
-    And I set "scene.BIMModelProperties.relating_type" to "{cube}"
-    And I press "bim.add_type_instance"
-    And I press "bim.add_type_instance"
+    And I set "scene.BIMModelProperties.relating_type_id" to "{cube}"
+    And I press "bim.add_constr_type_instance"
+    And I press "bim.add_constr_type_instance"
     And the object "IfcWall/Wall" is selected
     When the variable "representation" is "{ifc}.by_type('IfcWall')[0].Representation.Representations[1].id()"
     And I press "bim.remove_representation(representation_id={representation})"
@@ -339,8 +339,8 @@ Scenario: Override duplicate move - copying a type instance with a representatio
     And I press "bim.assign_class"
     And I set "scene.BIMModelProperties.ifc_class" to "IfcWallType"
     And the variable "cube" is "{ifc}.by_type('IfcWallType')[0].id()"
-    And I set "scene.BIMModelProperties.relating_type" to "{cube}"
-    And I press "bim.add_type_instance"
+    And I set "scene.BIMModelProperties.relating_type_id" to "{cube}"
+    And I press "bim.add_constr_type_instance"
     And the object "IfcWall/Wall" is selected
     When I press "object.duplicate_move"
     Then the object "IfcWall/Wall.001" exists
diff --git a/src/blenderbim/test/bim/feature/model.feature b/src/blenderbim/test/bim/feature/model.feature
index 49b85e9641..cd950f888d 100644
--- a/src/blenderbim/test/bim/feature/model.feature
+++ b/src/blenderbim/test/bim/feature/model.feature
@@ -10,8 +10,8 @@ Scenario: Add type instance - add from a mesh
     And I press "bim.assign_class"
     And I set "scene.BIMModelProperties.ifc_class" to "IfcWallType"
     And the variable "cube" is "{ifc}.by_type('IfcWallType')[0].id()"
-    And I set "scene.BIMModelProperties.relating_type" to "{cube}"
-    When I press "bim.add_type_instance"
+    And I set "scene.BIMModelProperties.relating_type_id" to "{cube}"
+    When I press "bim.add_constr_type_instance"
     Then the object "IfcWall/Wall" exists
 
 Scenario: Add type instance - add from an empty
@@ -23,8 +23,8 @@ Scenario: Add type instance - add from an empty
     And I press "bim.assign_class"
     And I set "scene.BIMModelProperties.ifc_class" to "IfcWallType"
     And the variable "empty" is "{ifc}.by_type('IfcWallType')[0].id()"
-    And I set "scene.BIMModelProperties.relating_type" to "{empty}"
-    When I press "bim.add_type_instance"
+    And I set "scene.BIMModelProperties.relating_type_id" to "{empty}"
+    When I press "bim.add_constr_type_instance"
     Then the object "IfcWall/Wall" exists
 
 Scenario: Add type instance - add a mesh where existing instances have changed context
@@ -36,18 +36,51 @@ Scenario: Add type instance - add a mesh where existing instances have changed c
     And I press "bim.assign_class"
     And I set "scene.BIMModelProperties.ifc_class" to "IfcWallType"
     And the variable "cube" is "{ifc}.by_type('IfcWallType')[0].id()"
-    And I set "scene.BIMModelProperties.relating_type" to "{cube}"
-    And I press "bim.add_type_instance"
+    And I set "scene.BIMModelProperties.relating_type_id" to "{cube}"
+    And I press "bim.add_constr_type_instance"
     And the object "IfcWall/Wall" data is a "Tessellation" representation of "Model/Body/MODEL_VIEW"
     And the object "IfcWall/Wall" is selected
     And the variable "context" is "[c for c in {ifc}.by_type('IfcGeometricRepresentationSubContext') if c.TargetView == 'PLAN_VIEW'][0].id()"
     And I set "scene.BIMRootProperties.contexts" to "{context}"
     And I press "bim.add_representation"
     And the object "IfcWall/Wall" data is a "Annotation2D" representation of "Plan/Annotation/PLAN_VIEW"
-    When I press "bim.add_type_instance"
+    When I press "bim.add_constr_type_instance"
     Then the object "IfcWall/Wall" data is a "Annotation2D" representation of "Plan/Annotation/PLAN_VIEW"
     And the object "IfcWall/Wall.001" data is a "Annotation2D" representation of "Plan/Annotation/PLAN_VIEW"
 
+Scenario: Preview one type on the Construction Type Browser
+    Given an empty IFC project
+    And I load the demo construction library
+    When I display the construction type browser
+    And I preview only one asset on the construction type browser
+    And I set "scene.BIMModelProperties.ifc_class_browser" to "IfcColumnType"
+    And I set "scene.BIMModelProperties.relating_type_browser" to "DEMO2"
+    And I select the browser construction type
+    Then "scene.BIMModelProperties.ifc_class" is "IfcColumnType"
+    And construction type is DEMO2
+    And objects starting with "IfcColumn/" do not exist
+    And the construction type "IfcColumnType"/"DEMO2" has a preview
+
+Scenario: Preview one class on the construction type browser
+    Given an empty IFC project
+    And I load the demo construction library
+    When I display the construction type browser
+    And I preview all available assets on the construction type browser
+    And I set "scene.BIMModelProperties.ifc_class_browser" to "IfcWallType"
+    Then "scene.BIMModelProperties.ifc_class_browser" is "IfcWallType"
+    And objects starting with "IfcWall/" do not exist
+    And all construction types for "IfcWallType" have a preview
+
+Scenario: Add one type from the Construction Type Browser
+    Given an empty IFC project
+    And I load the demo construction library
+    When I display the construction type browser
+    And I preview only one asset on the construction type browser
+    And I set "scene.BIMModelProperties.ifc_class_browser" to "IfcColumnType"
+    And I set "scene.BIMModelProperties.relating_type_browser" to "DEMO2"
+    And I add the browser construction type
+    Then the object "IfcColumn/Column" exists
+
 Scenario: Add grid
     Given an empty IFC project
     When I press "mesh.add_grid"
diff --git a/src/blenderbim/test/bim/test_feature.py b/src/blenderbim/test/bim/test_feature.py
index 579930012f..d964e883b9 100644
--- a/src/blenderbim/test/bim/test_feature.py
+++ b/src/blenderbim/test/bim/test_feature.py
@@ -23,6 +23,7 @@ import ifcopenshell
 import blenderbim.tool as tool
 import blenderbim.bim
 from blenderbim.bim.ifc import IfcStore
+from blenderbim.bim.module.model.data import AuthoringData
 from pytest_bdd import scenarios, given, when, then, parsers
 from mathutils import Vector
 
@@ -108,6 +109,7 @@ def i_add_a_new_collection_item(collection):
         assert False, "Collection does not exist"
 
 
+
 @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):
@@ -507,7 +509,16 @@ def the_collection_name1_is_in_the_collection_name2(name1, name2):
 
 @then(parsers.parse('the object "{name}" does not exist'))
 def the_object_name_does_not_exist(name):
-    assert bpy.data.objects.get(name) is None, "Object exists"
+    obj = bpy.data.objects.get(name)
+    assert obj is None or len(obj.users_collection) == 0, "Object exists"
+
+
+@then(parsers.parse('objects starting with "{name}" do not exist'))
+def objects_not_exist_starting_with(name):
+    objs = [obj for obj in bpy.data.objects if obj.name.startswith(name) and len(obj.users_collection) > 0]
+    if len(objs) > 0:
+        assert False, f'{len(objs)} objects starting with "{name}" exist'
+    assert True
 
 
 @then(parsers.parse('the object "{name}" is at "{location}"'))
@@ -562,3 +573,108 @@ def the_file_name_should_contain_value(name, value):
 @then(parsers.parse('the object "{name}" has no modifiers'))
 def the_object_name_has_no_modifiers(name):
     assert len(the_object_name_exists(name).modifiers) == 0
+
+
+@then(parsers.parse('the construction type "{ifc_class}"/"{relating_type}" has a preview'))
+def the_construction_type_has_a_preview(ifc_class, relating_type):
+    if "preview_constr_types" not in AuthoringData.data:
+        assert False, 'There are no previews loaded'
+    preview_constr_types = AuthoringData.data["preview_constr_types"]
+    if ifc_class not in preview_constr_types:
+        assert False, f'Construction class {ifc_class} has no available previews'
+    relating_type_id = AuthoringData.relating_type_id_by_name(ifc_class, relating_type)
+    if relating_type_id is None:
+        assert False, f'No construction type {ifc_class}/{relating_type} was found'
+    if relating_type_id not in preview_constr_types[ifc_class]:
+        assert False, f'Construction type {ifc_class}/{relating_type} has no available previews'
+    preview_data = preview_constr_types[ifc_class][relating_type_id]
+    if 'icon_id' not in preview_data:
+        assert False, f'Construction type {ifc_class}/{relating_type} has a preview, but no assigned icon_id'
+    icon_id = preview_data["icon_id"]
+    if not isinstance(icon_id, int):
+        assert False, f'Construction type {ifc_class}/{relating_type} has an invalid icon_id {icon_id}'
+    # Note: icon_id must be > 0 in UI mode, but asset_generate_preview() doesn't work headlessly -> skipping for now
+    # if icon_id == 0:
+    #     assert False, f'Construction type {ifc_class}/{relating_type} has the default null value for icon_id'
+    assert True
+
+
+@then("there is a Construction Type preview")
+def there_is_a_construction_type_preview():
+    props = bpy.context.scene.BIMModelProperties
+    assert props.icon_id > 0, f"There isn't a Construction Type preview"
+
+
+@then(parsers.parse('all construction types for "{ifc_class}" have a preview'))
+def all_construction_types_have_a_preview(ifc_class):
+    if "preview_constr_types" not in AuthoringData.data:
+        assert False, 'There are no previews loaded'
+    preview_constr_types = AuthoringData.data["preview_constr_types"]
+    if ifc_class not in preview_constr_types:
+        assert False, f'Construction class {ifc_class} has no available previews'
+    constr_class_occurrences = AuthoringData.constr_class_entities(ifc_class)
+    for constr_class_entity in constr_class_occurrences:
+        the_construction_type_has_a_preview(ifc_class, constr_class_entity.Name)
+
+
+@given("I load the demo construction library")
+@when("I load the demo construction library")
+def i_add_a_construction_library():
+    lib_path = './blenderbim/bim/data/libraries/IFC4 Demo Library.ifc'
+    bpy.ops.bim.select_library_file(filepath=lib_path, append_all=True)
+
+
+@given("I display the construction type browser")
+@when("I display the construction type browser")
+def i_display_the_construction_type_browser():
+    bpy.ops.bim.display_relating_types('INVOKE_DEFAULT')
+
+
+@given("I preview only one asset on the construction type browser")
+@when("I preview only one asset on the construction type browser")
+def i_preview_one_construction_type():
+    bpy.context.scene.BIMModelProperties.unfold_relating_types = False
+
+
+@given("I preview all available assets on the construction type browser")
+@when("I preview all available assets on the construction type browser")
+def i_preview_all_construction_types():
+    bpy.context.scene.BIMModelProperties.unfold_relating_types = True
+
+
+@given("I select the browser construction type")
+@when("I select the browser construction type")
+def i_select_the_active_construction_type():
+    props = bpy.context.scene.BIMModelProperties
+    bpy.ops.bim.select_construction_type(
+        ifc_class=props.ifc_class_browser, relating_type_id=props.relating_type_id_browser
+    )
+
+
+@given("I add the browser construction type")
+@when("I add the browser construction type")
+def i_add_the_active_construction_type():
+    props = bpy.context.scene.BIMModelProperties
+    bpy.ops.bim.add_constr_type_instance(
+        ifc_class=props.ifc_class_browser, relating_type_id=int(props.relating_type_id_browser)
+    )
+
+
+@then(parsers.parse("browser construction type is {relating_type_name}"))
+def browser_construction_type(relating_type_name):
+    props = bpy.context.scene.BIMModelProperties
+    relating_type_browser = AuthoringData.relating_type_name_by_id(props.ifc_class_browser, props.relating_type_id_browser)
+    assert relating_type_browser == relating_type_name, (f"Construction Type is a {relating_type_browser}, not " +
+                                                     f"a {relating_type_name}")
+
+
+@then(parsers.parse("construction type is {relating_type_name}"))
+def construction_type(relating_type_name):
+    props = bpy.context.scene.BIMModelProperties
+    relating_type = AuthoringData.relating_type_name_by_id(props.ifc_class, props.relating_type_id)
+    assert relating_type == relating_type_name, f"Construction Type is a {relating_type}, not a {relating_type_name}"
+
+
+@when("I move the cursor to the bottom left corner")
+def move_cursor_bottom_left():
+    bpy.context.window.cursor_warp(10, 10)
diff --git a/src/ifcopenshell-python/test/Sample-BIM-Files b/src/ifcopenshell-python/test/Sample-BIM-Files
index adadc7740b..2daf6c46ed 160000
--- a/src/ifcopenshell-python/test/Sample-BIM-Files
+++ b/src/ifcopenshell-python/test/Sample-BIM-Files
@@ -1 +1 @@
-Subproject commit adadc7740b7337f4cb0935ec8e84ba30ed4ca10d
+Subproject commit 2daf6c46ed9fc7a17259ef6d4c17c3553ef642cd