diff --git a/src/blenderbim/blenderbim/bim/module/model/opening.py b/src/blenderbim/blenderbim/bim/module/model/opening.py
index 2c21ba8352..6795a02147 100644
--- a/src/blenderbim/blenderbim/bim/module/model/opening.py
+++ b/src/blenderbim/blenderbim/bim/module/model/opening.py
@@ -24,10 +24,14 @@ import shapely
 import logging
 import numpy as np
 import ifcopenshell
+import ifcopenshell.api
+import ifcopenshell.geom
 import ifcopenshell.util.shape
 import ifcopenshell.util.element
 import ifcopenshell.util.shape_builder
+import ifcopenshell.util.placement
 import ifcopenshell.util.representation
+import ifcopenshell.util.unit
 import blenderbim.tool as tool
 import blenderbim.core.geometry
 import blenderbim.bim.import_ifc as import_ifc
diff --git a/src/blenderbim/blenderbim/bim/module/model/product.py b/src/blenderbim/blenderbim/bim/module/model/product.py
index 8d255a38a0..96cef5e893 100644
--- a/src/blenderbim/blenderbim/bim/module/model/product.py
+++ b/src/blenderbim/blenderbim/bim/module/model/product.py
@@ -25,9 +25,13 @@ import ifcopenshell.util.system
 import ifcopenshell.util.element
 import ifcopenshell.util.placement
 import ifcopenshell.util.representation
+import ifcopenshell.util.type
+import ifcopenshell.util.unit
 import blenderbim.tool as tool
+import blenderbim.core.aggregate
 import blenderbim.core.type
 import blenderbim.core.geometry
+import blenderbim.core.spatial
 from . import wall, slab, profile, mep
 from blenderbim.bim.ifc import IfcStore
 from blenderbim.bim.module.model.data import AuthoringData
@@ -273,7 +277,7 @@ class AddConstrTypeInstance(bpy.types.Operator):
             obj.location[2] = collection_obj.location[2] + bpy.context.scene.BIMModelProperties.rl2
 
     @staticmethod
-    def generate_layered_element(ifc_class, relating_type):
+    def generate_layered_element(ifc_class: str, relating_type: ifcopenshell.entity_instance) -> bool:
         layer_set_direction = None
 
         parametric = ifcopenshell.util.element.get_psets(relating_type).get("EPset_Parametric")
@@ -297,6 +301,7 @@ class AddConstrTypeInstance(bpy.types.Operator):
             material = ifcopenshell.util.element.get_material(tool.Ifc.get_entity(obj))
             material.LayerSetDirection = layer_set_direction
             return True
+        return False
 
 
 class ChangeTypePage(bpy.types.Operator, tool.Ifc.Operator):
diff --git a/src/blenderbim/blenderbim/bim/module/model/profile.py b/src/blenderbim/blenderbim/bim/module/model/profile.py
index 0b889ba035..8a4bde560d 100644
--- a/src/blenderbim/blenderbim/bim/module/model/profile.py
+++ b/src/blenderbim/blenderbim/bim/module/model/profile.py
@@ -21,14 +21,18 @@ import copy
 import bmesh
 import mathutils.geometry
 import ifcopenshell
+import ifcopenshell.api
 import ifcopenshell.util.type
 import ifcopenshell.util.unit
 import ifcopenshell.util.element
+import ifcopenshell.util.placement
+import ifcopenshell.util.representation
 import blenderbim.bim.handler
 import blenderbim.tool as tool
 import blenderbim.core.type
 import blenderbim.core.geometry
 import blenderbim.core.material
+import blenderbim.core.root
 from math import pi, degrees, inf
 from mathutils import Vector, Matrix, Quaternion
 from blenderbim.bim.module.geometry.helper import Helper
diff --git a/src/blenderbim/blenderbim/bim/module/model/slab.py b/src/blenderbim/blenderbim/bim/module/model/slab.py
index fb042a9046..de1d44715b 100644
--- a/src/blenderbim/blenderbim/bim/module/model/slab.py
+++ b/src/blenderbim/blenderbim/bim/module/model/slab.py
@@ -29,6 +29,7 @@ import ifcopenshell.util.type
 import blenderbim.bim.handler
 import blenderbim.core.type
 import blenderbim.core.geometry
+import blenderbim.core.root
 import blenderbim.tool as tool
 from math import radians
 from mathutils import Vector, Matrix
@@ -113,7 +114,7 @@ def calculate_quantities(usecase_path, ifc_file, settings):
 
 
 class DumbSlabGenerator:
-    def __init__(self, relating_type):
+    def __init__(self, relating_type: ifcopenshell.entity_instance):
         self.relating_type = relating_type
 
     def generate(self):
diff --git a/src/blenderbim/blenderbim/bim/module/model/wall.py b/src/blenderbim/blenderbim/bim/module/model/wall.py
index 59f49b254b..3463cb5f78 100644
--- a/src/blenderbim/blenderbim/bim/module/model/wall.py
+++ b/src/blenderbim/blenderbim/bim/module/model/wall.py
@@ -24,7 +24,9 @@ import ifcopenshell
 import ifcopenshell.api
 import ifcopenshell.util.unit
 import ifcopenshell.util.element
+import ifcopenshell.util.placement
 import ifcopenshell.util.representation
+import ifcopenshell.util.type
 import mathutils.geometry
 import blenderbim.bim.handler
 import blenderbim.core.type
diff --git a/src/blenderbim/test/tool/test_root.py b/src/blenderbim/test/tool/test_root.py
index 448fb4bc4d..099880df3f 100644
--- a/src/blenderbim/test/tool/test_root.py
+++ b/src/blenderbim/test/tool/test_root.py
@@ -18,6 +18,7 @@
 
 import bpy
 import ifcopenshell
+import ifcopenshell.api
 import blenderbim.core.tool
 import blenderbim.tool as tool
 from test.bim.bootstrap import NewFile
diff --git a/src/ifcopenshell-python/ifcopenshell/api/type/map_type_representations.py b/src/ifcopenshell-python/ifcopenshell/api/type/map_type_representations.py
index b8480dc211..940fd25902 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/type/map_type_representations.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/type/map_type_representations.py
@@ -22,7 +22,12 @@ import ifcopenshell.util.element
 
 
 class Usecase:
-    def __init__(self, file, related_object=None, relating_type=None):
+    def __init__(
+        self,
+        file: ifcopenshell.file,
+        related_object: ifcopenshell.entity_instance,
+        relating_type: ifcopenshell.entity_instance,
+    ):
         """Ensures that all occurrences has the same representation as the type
 
         If a type has a representation, all occurrences must have the same
@@ -87,7 +92,7 @@ class Usecase:
             "relating_type": relating_type,
         }
 
-    def execute(self):
+    def execute(self) -> None:
         if not self.settings["relating_type"].RepresentationMaps:
             return
         representations = []
diff --git a/src/ifcopenshell-python/ifcopenshell/util/element.py b/src/ifcopenshell-python/ifcopenshell/util/element.py
index 4f6ead203b..4e1a03eb1e 100644
--- a/src/ifcopenshell-python/ifcopenshell/util/element.py
+++ b/src/ifcopenshell-python/ifcopenshell/util/element.py
@@ -19,7 +19,7 @@
 from __future__ import annotations
 import ifcopenshell
 import ifcopenshell.util.element
-from typing import Any, Callable, Optional, Union
+from typing import Any, Callable, Optional, Union, Literal, overload
 
 
 def get_pset(
@@ -53,13 +53,13 @@ def get_pset(
     :type should_inherit: bool,optional
     :return: A dictionary of property names and values, or a single value if a
         property is specified.
-    :rtype: dict[str, Any]
+    :rtype: Union[Any, dict[str, Any]]
 
     Example:
 
     .. code:: python
 
-        element = ifcopenshell.by_type("IfcWall")[0]
+        element = ifc_file.by_type("IfcWall")[0]
         psets_and_qtos = ifcopenshell.util.element.get_pset(element, "Pset_WallCommon")
     """
     pset = None
@@ -132,6 +132,8 @@ def get_psets(
     :type qtos_only: bool,optional
     :param should_inherit: Default as True. Set to false if you don't want to inherit property sets from the Type.
     :type should_inherit: bool,optional
+    :param verbose: More detailed prop values, defaults to False.
+    :type verbose: bool,optional
     :return: Key, value pair of psets' names and their properties' names & values
     :rtype: dict[str, dict[str, Any]]
 
@@ -139,7 +141,7 @@ def get_psets(
 
     .. code:: python
 
-        element = ifcopenshell.by_type("IfcWall")[0]
+        element = ifc_file.by_type("IfcWall")[0]
         psets = ifcopenshell.util.element.get_psets(element, psets_only=True)
         qsets = ifcopenshell.util.element.get_psets(element, qtos_only=True)
         psets_and_qtos = ifcopenshell.util.element.get_psets(element)
@@ -173,9 +175,20 @@ def get_psets(
     return psets
 
 
+@overload
 def get_property_definition(
-    definition: ifcopenshell.entity_instance, prop: Optional[str] = None, verbose=False
+    definition: Optional[ifcopenshell.entity_instance], prop: None = None, verbose=False
+) -> dict[str, Any]: ...
+@overload
+def get_property_definition(definition: Optional[ifcopenshell.entity_instance], prop: str, verbose=False) -> Any: ...
+@overload
+def get_property_definition(definition: None, prop: None = None, verbose: bool = False) -> None: ...
+def get_property_definition(
+    definition: Optional[ifcopenshell.entity_instance], prop: Optional[str] = None, verbose=False
 ) -> Union[Any, dict[str, Any]]:
+    """if prop name is not provided in `prop`, will return dict of all available properties
+    otherwise will return the value of the specified `prop`.
+    """
     if not definition:
         return
 
@@ -214,6 +227,12 @@ def get_property_definition(
     return props
 
 
+@overload
+def get_quantity(quantities: list[ifcopenshell.entity_instance], name: str, verbose: Literal[False] = False) -> Any: ...
+@overload
+def get_quantity(
+    quantities: list[ifcopenshell.entity_instance], name: str, verbose: Literal[True]
+) -> dict[str, Any]: ...
 def get_quantity(
     quantities: list[ifcopenshell.entity_instance], name: str, verbose=False
 ) -> Union[Any, dict[str, Any]]:
@@ -232,7 +251,17 @@ def get_quantity(
         return result
 
 
-def get_quantities(quantities: list[ifcopenshell.entity_instance], verbose=False) -> dict[str, dict[str, Any]]:
+@overload
+def get_quantities(
+    quantities: list[ifcopenshell.entity_instance], verbose: Literal[False] = False
+) -> dict[str, Any]: ...
+@overload
+def get_quantities(
+    quantities: list[ifcopenshell.entity_instance], verbose: Literal[True]
+) -> dict[str, dict[str, Any]]: ...
+def get_quantities(
+    quantities: list[ifcopenshell.entity_instance], verbose=False
+) -> dict[str, Union[Any, dict[str, Any]]]:
     results = {}
     for quantity in quantities or []:
         if quantity.is_a("IfcPhysicalSimpleQuantity"):
@@ -257,6 +286,12 @@ def get_quantities(quantities: list[ifcopenshell.entity_instance], verbose=False
     return results
 
 
+@overload
+def get_property(properties: list[ifcopenshell.entity_instance], name: str, verbose: Literal[False] = False) -> Any: ...
+@overload
+def get_property(
+    properties: list[ifcopenshell.entity_instance], name: str, verbose: Literal[True]
+) -> dict[str, Any]: ...
 def get_property(
     properties: list[ifcopenshell.entity_instance], name: str, verbose=False
 ) -> Union[Any, dict[str, Any]]:
@@ -285,7 +320,17 @@ def get_property(
         return result
 
 
-def get_properties(properties: list[ifcopenshell.entity_instance], verbose=False) -> dict[str, dict[str, Any]]:
+@overload
+def get_properties(
+    properties: list[ifcopenshell.entity_instance], verbose: Literal[False] = False
+) -> dict[str, Any]: ...
+@overload
+def get_properties(
+    properties: list[ifcopenshell.entity_instance], verbose: Literal[True]
+) -> dict[str, dict[str, Any]]: ...
+def get_properties(
+    properties: list[ifcopenshell.entity_instance], verbose=False
+) -> dict[str, Union[Any, dict[str, Any]]]:
     results = {}
     for prop in properties or []:
         ifc_class = prop.is_a()
@@ -433,7 +478,7 @@ def get_shape_aspects(element: ifcopenshell.entity_instance) -> list[ifcopenshel
 
 def get_material(
     element: ifcopenshell.entity_instance, should_skip_usage=False, should_inherit=True
-) -> ifcopenshell.entity_instance:
+) -> Union[ifcopenshell.entity_instance, None]:
     """Gets the material of the element
 
     The material may be a single material, material set (layered, profiled, or
@@ -449,8 +494,8 @@ def get_material(
     :param should_inherit: If True, any inherited materials from associated
         types will be considered.
     :type should_inherit: bool
-    :return: The associated material of the element.
-    :rtype: ifcopenshell.entity_instance.entity_instance
+    :return: The associated material of the element or `None`.
+    :rtype: Union[ifcopenshell.entity_instance.entity_instance, None]
 
     Example:
 
diff --git a/src/ifcopenshell-python/ifcopenshell/util/system.py b/src/ifcopenshell-python/ifcopenshell/util/system.py
index 0c8789a098..3a5be9693f 100644
--- a/src/ifcopenshell-python/ifcopenshell/util/system.py
+++ b/src/ifcopenshell-python/ifcopenshell/util/system.py
@@ -17,9 +17,10 @@
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
 
-import ifcopenshell.util
+import ifcopenshell.util.system
+from typing import Optional, Union, Literal
 
-group_types = {
+group_types: dict[str, tuple[str, ...]] = {
     "IfcZone": ("IfcZone", "IfcSpace", "IfcSpatialZone"),
     "IfcBuiltSystem": (
         "IfcBuiltElement",
@@ -39,22 +40,24 @@ group_types = {
     "IfcGroup": ("IfcObjectDefinition",),
 }
 
+FLOW_DIRECTION = Literal["SINK", "SOURCE", "SOURCEANDSINK", "NOTEDEFINED"]
 
-def is_assignable(product, system) -> bool:
+
+def is_assignable(product: ifcopenshell.entity_instance, system: ifcopenshell.entity_instance) -> bool:
     for assignable in group_types.get(system.is_a(), ()):
         if product.is_a(assignable):
             return True
     return False
 
 
-def get_system_elements(system):
+def get_system_elements(system: ifcopenshell.entity_instance) -> list[ifcopenshell.entity_instance]:
     results = []
     for rel in system.IsGroupedBy:
         results.extend(rel.RelatedObjects)
     return results
 
 
-def get_element_systems(element):
+def get_element_systems(element: ifcopenshell.entity_instance) -> list[ifcopenshell.entity_instance]:
     results = []
     for rel in element.HasAssignments:
         if rel.is_a("IfcRelAssignsToGroup") and rel.RelatingGroup.is_a() in (
@@ -67,7 +70,9 @@ def get_element_systems(element):
     return results
 
 
-def get_ports(element, flow_direction=None):
+def get_ports(
+    element: ifcopenshell.entity_instance, flow_direction: Optional[FLOW_DIRECTION] = None
+) -> list[ifcopenshell.entity_instance]:
     results = []
     for rel in getattr(element, "IsNestedBy", []) or []:
         for port in rel.RelatedObjects:
@@ -85,14 +90,14 @@ def get_ports(element, flow_direction=None):
     return results
 
 
-def get_connected_port(port):
+def get_connected_port(port: ifcopenshell.entity_instance) -> Union[ifcopenshell.entity_instance, None]:
     for rel in port.ConnectedTo:
         return rel.RelatedPort
     for rel in port.ConnectedFrom:
         return rel.RelatingPort
 
 
-def get_port_element(port):
+def get_port_element(port: ifcopenshell.entity_instance) -> ifcopenshell.entity_instance:
     if hasattr(port, "Nests"):
         for rel in port.Nests:
             return rel.RelatingObject
@@ -102,7 +107,9 @@ def get_port_element(port):
             return rel.RelatedElement
 
 
-def get_connected_to(element, flow_direction=None):
+def get_connected_to(
+    element: ifcopenshell.entity_instance, flow_direction: Optional[FLOW_DIRECTION] = None
+) -> list[ifcopenshell.entity_instance]:
     results = []
     for port in ifcopenshell.util.system.get_ports(element, flow_direction=flow_direction):
         for rel in port.ConnectedTo:
@@ -115,7 +122,9 @@ def get_connected_to(element, flow_direction=None):
     return results
 
 
-def get_connected_from(element, flow_direction=None):
+def get_connected_from(
+    element: ifcopenshell.entity_instance, flow_direction: Optional[FLOW_DIRECTION] = None
+) -> list[ifcopenshell.entity_instance]:
     results = []
     for port in ifcopenshell.util.system.get_ports(element, flow_direction=flow_direction):
         for rel in port.ConnectedFrom:
diff --git a/src/ifcopenshell-python/test/api/project/test_append_asset.py b/src/ifcopenshell-python/test/api/project/test_append_asset.py
index 3e03be43d5..bca7a1580d 100644
--- a/src/ifcopenshell-python/test/api/project/test_append_asset.py
+++ b/src/ifcopenshell-python/test/api/project/test_append_asset.py
@@ -18,6 +18,7 @@
 
 import test.bootstrap
 import ifcopenshell.api
+import ifcopenshell.util.element
 
 
 class TestAppendAsset(test.bootstrap.IFC4):
diff --git a/src/ifcopenshell-python/test/api/pset/test_add_pset.py b/src/ifcopenshell-python/test/api/pset/test_add_pset.py
index 3170b53abd..9d18e16ee2 100644
--- a/src/ifcopenshell-python/test/api/pset/test_add_pset.py
+++ b/src/ifcopenshell-python/test/api/pset/test_add_pset.py
@@ -18,6 +18,7 @@
 
 import test.bootstrap
 import ifcopenshell.api
+import ifcopenshell.util.element
 
 
 class TestAddPset(test.bootstrap.IFC4):
diff --git a/src/ifcopenshell-python/test/api/pset/test_add_qto.py b/src/ifcopenshell-python/test/api/pset/test_add_qto.py
index d4cbd74a5c..3afb847c89 100644
--- a/src/ifcopenshell-python/test/api/pset/test_add_qto.py
+++ b/src/ifcopenshell-python/test/api/pset/test_add_qto.py
@@ -18,6 +18,7 @@
 
 import test.bootstrap
 import ifcopenshell.api
+import ifcopenshell.util.element
 
 
 class TestAddQto(test.bootstrap.IFC4):
diff --git a/src/ifcopenshell-python/test/api/root/test_copy_class.py b/src/ifcopenshell-python/test/api/root/test_copy_class.py
index 5fcaf8cb90..a4177150fa 100644
--- a/src/ifcopenshell-python/test/api/root/test_copy_class.py
+++ b/src/ifcopenshell-python/test/api/root/test_copy_class.py
@@ -19,6 +19,8 @@
 import numpy
 import test.bootstrap
 import ifcopenshell.api
+import ifcopenshell.util
+import ifcopenshell.util.system
 
 
 class TestCopyClass(test.bootstrap.IFC4):
diff --git a/src/ifcopenshell-python/test/api/system/test_assign_port.py b/src/ifcopenshell-python/test/api/system/test_assign_port.py
index 836222298c..130e208b02 100644
--- a/src/ifcopenshell-python/test/api/system/test_assign_port.py
+++ b/src/ifcopenshell-python/test/api/system/test_assign_port.py
@@ -19,6 +19,7 @@
 import numpy
 import test.bootstrap
 import ifcopenshell.api
+import ifcopenshell.util.placement
 import ifcopenshell.util.system