diff --git a/docs/sap-spec/PCDF_Spec_Rev-06b_12_May_2021.pdf b/docs/sap-spec/PCDF_Spec_Rev-06b_12_May_2021.pdf
new file mode 100644
index 00000000..22c40945
Binary files /dev/null and b/docs/sap-spec/PCDF_Spec_Rev-06b_12_May_2021.pdf differ
diff --git a/docs/sap-spec/rdsap-10-specification-2025-06-10.pdf b/docs/sap-spec/RdSAP 10 Specification 10-06-2025.pdf
similarity index 100%
rename from docs/sap-spec/rdsap-10-specification-2025-06-10.pdf
rename to docs/sap-spec/RdSAP 10 Specification 10-06-2025.pdf
diff --git a/packages/domain/src/domain/sap/rdsap/tests/fixtures/golden/0535-9020-6509-0821-6222.json b/packages/domain/src/domain/sap/rdsap/tests/fixtures/golden/0535-9020-6509-0821-6222.json
new file mode 100644
index 00000000..a9221ca8
--- /dev/null
+++ b/packages/domain/src/domain/sap/rdsap/tests/fixtures/golden/0535-9020-6509-0821-6222.json
@@ -0,0 +1,513 @@
+{
+  "address_line_1": "67 Howick Park Drive",
+  "address_line_2": "Penwortham",
+  "air_tightness": {
+    "description": "(not tested)",
+    "energy_efficiency_rating": 0,
+    "environmental_efficiency_rating": 0
+  },
+  "assessment_type": "RdSAP",
+  "built_form": 2,
+  "calculation_software_version": "5.02r0316",
+  "cfl_fixed_lighting_bulbs_count": 6,
+  "co2_emissions_current": 2.5,
+  "co2_emissions_current_per_floor_area": 37,
+  "co2_emissions_potential": 2.2,
+  "completion_date": "2025-10-31",
+  "conservatory_type": 1,
+  "country_code": "ENG",
+  "created_at": "2025-10-31 17:58:26",
+  "current_energy_efficiency_band": "C",
+  "door_count": 1,
+  "draughtproofed_door_count": 0,
+  "dwelling_type": "Semi-detached house",
+  "energy_consumption_current": 201,
+  "energy_consumption_potential": 171,
+  "energy_rating_average": 60,
+  "energy_rating_current": 69,
+  "energy_rating_potential": 76,
+  "environmental_impact_current": 68,
+  "environmental_impact_potential": 72,
+  "extensions_count": 2,
+  "extract_fans_count": 2,
+  "floors": [
+    {
+      "description": "Suspended, no insulation (assumed)",
+      "energy_efficiency_rating": 0,
+      "environmental_efficiency_rating": 0
+    },
+    {
+      "description": "Suspended, insulated (assumed)",
+      "energy_efficiency_rating": 0,
+      "environmental_efficiency_rating": 0
+    }
+  ],
+  "habitable_room_count": 4,
+  "has_fixed_air_conditioning": "false",
+  "has_heated_separate_conservatory": "false",
+  "has_hot_water_cylinder": "false",
+  "heated_room_count": 4,
+  "heating_cost_current": {
+    "currency": "GBP",
+    "value": 763
+  },
+  "heating_cost_potential": {
+    "currency": "GBP",
+    "value": 705
+  },
+  "hot_water": {
+    "description": "From main system",
+    "energy_efficiency_rating": 4,
+    "environmental_efficiency_rating": 4
+  },
+  "hot_water_cost_current": {
+    "currency": "GBP",
+    "value": 155
+  },
+  "hot_water_cost_potential": {
+    "currency": "GBP",
+    "value": 155
+  },
+  "incandescent_fixed_lighting_bulbs_count": 0,
+  "inspection_date": "2025-10-29",
+  "insulated_door_count": 0,
+  "language_code": 1,
+  "led_fixed_lighting_bulbs_count": 17,
+  "lighting": {
+    "description": "Good lighting efficiency",
+    "energy_efficiency_rating": 4,
+    "environmental_efficiency_rating": 4
+  },
+  "lighting_cost_current": {
+    "currency": "GBP",
+    "value": 46
+  },
+  "lighting_cost_potential": {
+    "currency": "GBP",
+    "value": 46
+  },
+  "main_heating": [
+    {
+      "description": "Boiler and radiators, mains gas",
+      "energy_efficiency_rating": 4,
+      "environmental_efficiency_rating": 4
+    }
+  ],
+  "main_heating_controls": [
+    {
+      "description": "Programmer, room thermostat and TRVs",
+      "energy_efficiency_rating": 4,
+      "environmental_efficiency_rating": 4
+    }
+  ],
+  "measurement_type": 1,
+  "mechanical_ventilation": 0,
+  "multiple_glazed_proportion": 100,
+  "percent_draughtproofed": 90,
+  "post_town": "PRESTON",
+  "postcode": "PR1 0LX",
+  "potential_energy_efficiency_band": "C",
+  "pressure_test": 4,
+  "property_type": 0,
+  "region_code": 19,
+  "registration_date": "2025-10-31",
+  "renewable_heat_incentive": {
+    "space_heating_existing_dwelling": 7428.0,
+    "water_heating": 2074.92
+  },
+  "report_type": 2,
+  "roofs": [
+    {
+      "description": "Pitched, 300 mm loft insulation",
+      "energy_efficiency_rating": 5,
+      "environmental_efficiency_rating": 5
+    },
+    {
+      "description": "Pitched, insulated",
+      "energy_efficiency_rating": 5,
+      "environmental_efficiency_rating": 5
+    }
+  ],
+  "sap_building_parts": [
+    {
+      "building_part_number": 1,
+      "construction_age_band": "C",
+      "floor_heat_loss": 7,
+      "floor_insulation_thickness": "NI",
+      "identifier": "Main Dwelling",
+      "party_wall_construction": 2,
+      "roof_construction": 4,
+      "roof_insulation_location": 2,
+      "roof_insulation_thickness": "300mm",
+      "sap_floor_dimensions": [
+        {
+          "floor": 0,
+          "floor_construction": 2,
+          "floor_insulation": 1,
+          "heat_loss_perimeter": {
+            "quantity": "metres",
+            "value": 11.99
+          },
+          "party_wall_length": {
+            "quantity": "metres",
+            "value": 6.94
+          },
+          "room_height": {
+            "quantity": "metres",
+            "value": 2.39
+          },
+          "total_floor_area": {
+            "quantity": "square metres",
+            "value": 30.45
+          }
+        },
+        {
+          "floor": 1,
+          "heat_loss_perimeter": {
+            "quantity": "metres",
+            "value": 13.55
+          },
+          "party_wall_length": {
+            "quantity": "metres",
+            "value": 6.94
+          },
+          "room_height": {
+            "quantity": "metres",
+            "value": 2.28
+          },
+          "total_floor_area": {
+            "quantity": "square metres",
+            "value": 30.77
+          }
+        }
+      ],
+      "wall_construction": 4,
+      "wall_dry_lined": "N",
+      "wall_insulation_thickness": "NI",
+      "wall_insulation_type": 2,
+      "wall_thickness": 280,
+      "wall_thickness_measured": "Y"
+    },
+    {
+      "building_part_number": 2,
+      "construction_age_band": "M",
+      "floor_heat_loss": 7,
+      "floor_insulation_thickness": "NI",
+      "identifier": "Extension 1",
+      "party_wall_construction": "NA",
+      "roof_construction": 8,
+      "roof_insulation_location": 7,
+      "sap_floor_dimensions": [
+        {
+          "floor": 0,
+          "floor_construction": 2,
+          "floor_insulation": 1,
+          "heat_loss_perimeter": {
+            "quantity": "metres",
+            "value": 6.67
+          },
+          "party_wall_length": {
+            "quantity": "metres",
+            "value": 0
+          },
+          "room_height": {
+            "quantity": "metres",
+            "value": 2.48
+          },
+          "total_floor_area": {
+            "quantity": "square metres",
+            "value": 5.37
+          }
+        }
+      ],
+      "sloping_ceiling_insulation_thickness": "AB",
+      "wall_construction": 4,
+      "wall_dry_lined": "N",
+      "wall_insulation_thickness": "NI",
+      "wall_insulation_type": 4,
+      "wall_thickness": 280,
+      "wall_thickness_measured": "Y"
+    },
+    {
+      "building_part_number": 3,
+      "construction_age_band": "C",
+      "floor_heat_loss": 1,
+      "floor_insulation_thickness": "NI",
+      "identifier": "Extension 2",
+      "party_wall_construction": "NA",
+      "roof_construction": 8,
+      "roof_insulation_location": 7,
+      "sap_floor_dimensions": [
+        {
+          "floor": 0,
+          "floor_construction": 2,
+          "floor_insulation": 1,
+          "heat_loss_perimeter": {
+            "quantity": "metres",
+            "value": 2.81
+          },
+          "party_wall_length": {
+            "quantity": "metres",
+            "value": 0
+          },
+          "room_height": {
+            "quantity": "metres",
+            "value": 2.1
+          },
+          "total_floor_area": {
+            "quantity": "square metres",
+            "value": 1.92
+          }
+        }
+      ],
+      "sloping_ceiling_insulation_thickness": "AB",
+      "wall_construction": 4,
+      "wall_dry_lined": "N",
+      "wall_insulation_thickness": "NI",
+      "wall_insulation_type": 2,
+      "wall_thickness": 280,
+      "wall_thickness_measured": "Y"
+    }
+  ],
+  "sap_energy_source": {
+    "electricity_smart_meter_present": "true",
+    "gas_smart_meter_present": "true",
+    "is_dwelling_export_capable": "false",
+    "mains_gas": "Y",
+    "meter_type": 2,
+    "photovoltaic_supply": {
+      "none_or_no_details": {
+        "percent_roof_area": 0
+      }
+    },
+    "pv_connection": 0,
+    "wind_turbines_count": 0,
+    "wind_turbines_terrain_type": 2
+  },
+  "sap_heating": {
+    "cylinder_size": 1,
+    "has_fixed_air_conditioning": "false",
+    "immersion_heating_type": "NA",
+    "main_heating_details": [
+      {
+        "boiler_flue_type": 2,
+        "central_heating_pump_age": 0,
+        "emitter_temperature": 0,
+        "fan_flue_present": "Y",
+        "has_fghrs": "N",
+        "heat_emitter_type": 1,
+        "main_fuel_type": 26,
+        "main_heating_category": 2,
+        "main_heating_control": 2106,
+        "main_heating_data_source": 1,
+        "main_heating_fraction": 1,
+        "main_heating_index_number": 17507,
+        "main_heating_number": 1
+      }
+    ],
+    "number_baths": 0,
+    "number_baths_wwhrs": 0,
+    "secondary_fuel_type": 26,
+    "secondary_heating_type": 605,
+    "shower_outlets": [
+      {
+        "shower_outlet": {
+          "shower_outlet_type": 1,
+          "shower_wwhrs": 1
+        }
+      }
+    ],
+    "water_heating_code": 901,
+    "water_heating_fuel": 26
+  },
+  "sap_version": 10.2,
+  "sap_windows": [
+    {
+      "draught_proofed": "true",
+      "glazing_gap": 12,
+      "glazing_type": 3,
+      "orientation": 8,
+      "permanent_shutters_insulated": "N",
+      "permanent_shutters_present": "N",
+      "pvc_frame": "true",
+      "window_height": 1.32,
+      "window_location": 0,
+      "window_type": 1,
+      "window_wall_type": 1,
+      "window_width": 2.53
+    },
+    {
+      "draught_proofed": "true",
+      "glazing_gap": 12,
+      "glazing_type": 3,
+      "orientation": 2,
+      "permanent_shutters_insulated": "N",
+      "permanent_shutters_present": "N",
+      "pvc_frame": "true",
+      "window_height": 1.3,
+      "window_location": 0,
+      "window_type": 1,
+      "window_wall_type": 1,
+      "window_width": 0.56
+    },
+    {
+      "draught_proofed": "true",
+      "glazing_type": 13,
+      "orientation": 4,
+      "permanent_shutters_insulated": "N",
+      "permanent_shutters_present": "N",
+      "window_height": 2.11,
+      "window_location": 1,
+      "window_type": 1,
+      "window_wall_type": 1,
+      "window_width": 3.02
+    },
+    {
+      "draught_proofed": "true",
+      "glazing_gap": 12,
+      "glazing_type": 3,
+      "orientation": 8,
+      "permanent_shutters_insulated": "N",
+      "permanent_shutters_present": "N",
+      "pvc_frame": "true",
+      "window_height": 1.53,
+      "window_location": 0,
+      "window_type": 1,
+      "window_wall_type": 1,
+      "window_width": 1.99
+    },
+    {
+      "draught_proofed": "true",
+      "glazing_gap": 12,
+      "glazing_type": 3,
+      "orientation": 2,
+      "permanent_shutters_insulated": "N",
+      "permanent_shutters_present": "N",
+      "pvc_frame": "true",
+      "window_height": 1.28,
+      "window_location": 0,
+      "window_type": 1,
+      "window_wall_type": 1,
+      "window_width": 1.04
+    },
+    {
+      "draught_proofed": "true",
+      "glazing_gap": 12,
+      "glazing_type": 3,
+      "orientation": 2,
+      "permanent_shutters_insulated": "N",
+      "permanent_shutters_present": "N",
+      "pvc_frame": "true",
+      "window_height": 1.28,
+      "window_location": 0,
+      "window_type": 1,
+      "window_wall_type": 1,
+      "window_width": 0.55
+    },
+    {
+      "draught_proofed": "true",
+      "glazing_gap": 12,
+      "glazing_type": 3,
+      "orientation": 2,
+      "permanent_shutters_insulated": "N",
+      "permanent_shutters_present": "N",
+      "pvc_frame": "true",
+      "window_height": 1.16,
+      "window_location": 0,
+      "window_type": 1,
+      "window_wall_type": 1,
+      "window_width": 0.85
+    },
+    {
+      "draught_proofed": "true",
+      "glazing_gap": 12,
+      "glazing_type": 3,
+      "orientation": 4,
+      "permanent_shutters_insulated": "N",
+      "permanent_shutters_present": "N",
+      "pvc_frame": "true",
+      "window_height": 1.29,
+      "window_location": 0,
+      "window_type": 1,
+      "window_wall_type": 1,
+      "window_width": 1.65
+    },
+    {
+      "draught_proofed": "true",
+      "glazing_gap": 12,
+      "glazing_type": 3,
+      "orientation": 1,
+      "permanent_shutters_insulated": "N",
+      "permanent_shutters_present": "N",
+      "pvc_frame": "true",
+      "window_height": 1.32,
+      "window_location": 0,
+      "window_type": 1,
+      "window_wall_type": 1,
+      "window_width": 1.29
+    }
+  ],
+  "schema_type": "RdSAP-Schema-21.0.1",
+  "schema_version_original": "21.0.1",
+  "secondary_heating": {
+    "description": "Room heaters, mains gas",
+    "energy_efficiency_rating": 0,
+    "environmental_efficiency_rating": 0
+  },
+  "solar_water_heating": "N",
+  "status": "entered",
+  "suggested_improvements": [
+    {
+      "energy_performance_rating": 71,
+      "environmental_impact_rating": 71,
+      "improvement_category": 5,
+      "improvement_details": {
+        "improvement_number": 57
+      },
+      "improvement_type": "W1",
+      "indicative_cost": "\u00a35,000 - \u00a310,000",
+      "sequence": 1,
+      "typical_saving": {
+        "currency": "GBP",
+        "value": 58
+      }
+    },
+    {
+      "energy_performance_rating": 76,
+      "environmental_impact_rating": 72,
+      "improvement_category": 5,
+      "improvement_details": {
+        "improvement_number": 34
+      },
+      "improvement_type": "U",
+      "indicative_cost": "\u00a38,000 - \u00a310,000",
+      "sequence": 2,
+      "typical_saving": {
+        "currency": "GBP",
+        "value": 196
+      }
+    }
+  ],
+  "tenure": 3,
+  "total_floor_area": 69,
+  "transaction_type": 15,
+  "uprn": 100010634425,
+  "uprn_source": "Energy Assessor",
+  "walls": [
+    {
+      "description": "Cavity wall, filled cavity",
+      "energy_efficiency_rating": 4,
+      "environmental_efficiency_rating": 4
+    },
+    {
+      "description": "Cavity wall, as built, insulated (assumed)",
+      "energy_efficiency_rating": 5,
+      "environmental_efficiency_rating": 5
+    }
+  ],
+  "window": {
+    "description": "Fully double glazed",
+    "energy_efficiency_rating": 3,
+    "environmental_efficiency_rating": 3
+  }
+}
\ No newline at end of file
diff --git a/packages/domain/src/domain/sap/worksheet/tests/test_dimensions.py b/packages/domain/src/domain/sap/worksheet/tests/test_dimensions.py
index 88811585..afd01852 100644
--- a/packages/domain/src/domain/sap/worksheet/tests/test_dimensions.py
+++ b/packages/domain/src/domain/sap/worksheet/tests/test_dimensions.py
@@ -468,7 +468,7 @@ def test_all_rir_shapes_apply_section_1_2_45m_convention_uniformly(
 ) -> None:
     """RdSAP §3.9.2 wall-area formulas and §3.10 detailed measurements
     are for §3 heat-loss U-value calculation, **not** §1 dimensions —
-    confirmed at docs/sap-spec/rdsap-10-specification-2025-06-10.pdf
+    confirmed at `docs/sap-spec/RdSAP 10 Specification 10-06-2025.pdf`
     pages 22-24. The §1 storey-height convention of 2.45 m from §3.9.1
     extends uniformly to every RR shape: each contributes exactly
     `floor_area` to TFA, `floor_area × 2.45` to volume, and +1 storey.