diff --git a/src/blenderbim/blenderbim/bim/module/model/data.py b/src/blenderbim/blenderbim/bim/module/model/data.py
index c5b44b9c8b..2f3b69a85c 100644
--- a/src/blenderbim/blenderbim/bim/module/model/data.py
+++ b/src/blenderbim/blenderbim/bim/module/model/data.py
@@ -333,25 +333,7 @@ class StairData:
 
     @classmethod
     def calculated_params(cls):
-        props = bpy.context.active_object.BIMStairProperties
-
-        if props.is_editing:
-            si_conversion = ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())
-            number_of_treads = props.number_of_treads
-            height = props.height / si_conversion
-            tread_run = props.tread_run / si_conversion
-        else:
-            data = cls.data["pset_data"]["data_dict"]
-            number_of_treads = data["number_of_treads"]
-            height = data["height"]
-            tread_run = data["tread_run"]
-
-        calculated_params = {}
-        number_of_rises = number_of_treads + 1
-        calculated_params["Number of risers"] = number_of_rises
-        calculated_params["Tread rise"] = round(height / number_of_rises, 5)
-        calculated_params["Length"] = round(tread_run * number_of_rises, 5)
-        return calculated_params
+        return tool.Model.get_active_stair_calculated_params(cls.data["pset_data"]["data_dict"])
 
 
 class SverchokData:
diff --git a/src/blenderbim/blenderbim/bim/module/model/ui.py b/src/blenderbim/blenderbim/bim/module/model/ui.py
index 4e2047996c..b6d07b9fff 100644
--- a/src/blenderbim/blenderbim/bim/module/model/ui.py
+++ b/src/blenderbim/blenderbim/bim/module/model/ui.py
@@ -259,8 +259,8 @@ class BIM_PT_stair(bpy.types.Panel):
             row = self.layout.row(align=True)
             row.label(text="Stair parameters", icon="IPO_CONSTANT")
 
-            stair_data = StairData.data["pset_data"]["data_dict"]
             if props.is_editing:
+                calculated_params = tool.Model.get_active_stair_calculated_params()
                 row = self.layout.row(align=True)
                 row.operator("bim.finish_editing_stair", icon="CHECKMARK", text="Finish Editing")
                 row.operator("bim.cancel_editing_stair", icon="CANCEL", text="")
@@ -269,6 +269,7 @@ class BIM_PT_stair(bpy.types.Panel):
                     self.layout.prop(props, prop_name)
                 regenerate_stair_mesh(context)
             else:
+                calculated_params = StairData.data["calculated_params"]
                 row.operator("bim.enable_editing_stair", icon="GREASEPENCIL", text="")
                 row.operator("bim.remove_stair", icon="X", text="")
                 row = self.layout.row(align=True)
@@ -278,7 +279,7 @@ class BIM_PT_stair(bpy.types.Panel):
                     row.label(text=str(prop_value))
 
             # calculated properties
-            for prop_name, prop_value in StairData.data["calculated_params"].items():
+            for prop_name, prop_value in calculated_params.items():
                 row = self.layout.row(align=True)
                 row.label(text=prop_name)
                 row.label(text=str(prop_value))
diff --git a/src/blenderbim/blenderbim/tool/model.py b/src/blenderbim/blenderbim/tool/model.py
index 54d24ba15e..11f0573d49 100644
--- a/src/blenderbim/blenderbim/tool/model.py
+++ b/src/blenderbim/blenderbim/tool/model.py
@@ -908,6 +908,27 @@ class Model(blenderbim.core.tool.Model):
     def is_parametric_door_active(cls):
         return (DoorData.is_loaded or not DoorData.load()) and DoorData.data["pset_data"]
 
+    @classmethod
+    def get_active_stair_calculated_params(cls, pset_data=None):
+        props = bpy.context.active_object.BIMStairProperties
+
+        if props.is_editing:
+            si_conversion = ifcopenshell.util.unit.calculate_unit_scale(tool.Ifc.get())
+            number_of_treads = props.number_of_treads
+            height = props.height / si_conversion
+            tread_run = props.tread_run / si_conversion
+        else:
+            number_of_treads = pset_data["number_of_treads"]
+            height = pset_data["height"]
+            tread_run = pset_data["tread_run"]
+
+        calculated_params = {}
+        number_of_rises = number_of_treads + 1
+        calculated_params["Number of risers"] = number_of_rises
+        calculated_params["Tread rise"] = round(height / number_of_rises, 5)
+        calculated_params["Length"] = round(tread_run * number_of_rises, 5)
+        return calculated_params
+
     @classmethod
     def generate_stair_2d_profile(
         cls,