diff --git a/model_data/simulation_system/generate_rdsap_change.py b/model_data/simulation_system/generate_rdsap_change.py
index 5bf8cde8..7c4c6029 100644
--- a/model_data/simulation_system/generate_rdsap_change.py
+++ b/model_data/simulation_system/generate_rdsap_change.py
@@ -16,7 +16,10 @@ from model_data.simulation_system.core.Settings import (
 from model_data.simulation_system.core.DataProcessor import DataProcessor
 from utils.s3 import save_dataframe_to_s3_parquet, read_from_s3, read_dataframe_from_s3_parquet
 from recommendations.rdsap_tables import england_wales_age_band_lookup
-from recommendations.recommendation_utils import get_wall_u_value, get_roof_u_value
+from recommendations.recommendation_utils import (
+    get_wall_u_value, get_roof_u_value, get_floor_u_value, estimate_perimeter_2_rooms, estimate_perimeter,
+    extract_insulation_thickness, get_wall_type
+)
 
 DATA_DIRECTORY = Path(__file__).parent / "model_data" / "simulation_system" / "data" / "all-domestic-certificates"
 
@@ -220,6 +223,7 @@ def make_uvalues(df):
 
         uprn = x["UPRN"]
         row_index = x["row_index"]
+        age_band = england_wales_age_band_lookup[x["CONSTRUCTION_AGE_BAND"]]
 
         # ~~~~~~~~~~~~~~~~~~
         # Walls
@@ -229,7 +233,7 @@ def make_uvalues(df):
         if pd.isnull(starting_wall_uvalue):
             starting_wall_uvalue = get_wall_u_value(
                 clean_description=x["walls_clean_description"],
-                age_band=england_wales_age_band_lookup[x["CONSTRUCTION_AGE_BAND"]],
+                age_band=age_band,
                 is_granite_or_whinstone=x["is_granite_or_whinstone"],
                 is_sandstone_or_limestone=x["is_sandstone_or_limestone"],
             )
@@ -239,7 +243,7 @@ def make_uvalues(df):
             if x["walls_clean_description"] != x["walls_clean_description_ENDING"]:
                 ending_wall_uvalue = get_wall_u_value(
                     clean_description=x["walls_clean_description_ENDING"],
-                    age_band=england_wales_age_band_lookup[x["CONSTRUCTION_AGE_BAND"]],
+                    age_band=age_band,
                     is_granite_or_whinstone=x["is_granite_or_whinstone"],
                     is_sandstone_or_limestone=x["is_sandstone_or_limestone"],
                 )
@@ -260,7 +264,7 @@ def make_uvalues(df):
                 is_flat=x["is_flat"],
                 is_pitched=x["is_pitched"],
                 is_at_rafters=x["is_at_rafters"],
-                age_band=england_wales_age_band_lookup[x["CONSTRUCTION_AGE_BAND"]]
+                age_band=age_band
             )
 
         ending_roof_uvalue = x["roof_thermal_transmittance_ENDING"]
@@ -275,12 +279,44 @@ def make_uvalues(df):
                 is_flat=x["is_flat"],
                 is_pitched=x["is_pitched"],
                 is_at_rafters=x["is_at_rafters"],
-                age_band=england_wales_age_band_lookup[x["CONSTRUCTION_AGE_BAND"]]
+                age_band=age_band
             )
 
         # ~~~~~~~~~~~~~~~~~~
         # Floor
         # ~~~~~~~~~~~~~~~~~~
+        perimeters = {}
+        for suffix in ["_STARTING", "_ENDING"]:
+            floor_area = x[f"TOTAL_FLOOR_AREA{suffix}"]
+            n_rooms = x["NUMBER_HABITABLE_ROOMS"]
+
+            perimeters[f"estimated_perimeter{suffix}"] = estimate_perimeter_2_rooms(floor_area) if n_rooms <= 2 else \
+                estimate_perimeter(floor_area, n_rooms)
+
+        floor_type = "suspended" if x["is_suspended"] else "solid"
+        wall_type = get_wall_type(**x)
+
+        starting_floor_uvalue = x["floor_thermal_transmittance"]
+        if pd.isnull(starting_floor_uvalue):
+            starting_floor_uvalue = get_floor_u_value(
+                floor_type=floor_type,
+                perimeter=perimeters["estimated_perimeter_STARTING"],
+                area=x[f"TOTAL_FLOOR_AREA_STARTING"],
+                insulation_thickness=extract_insulation_thickness(x["floor_insulation_thickness"]),
+                wall_type=wall_type,
+                age_band=age_band
+            )
+
+        ending_floor_uvalue = x["floor_thermal_transmittance_ENDING"]
+        if pd.isnull(ending_floor_uvalue):
+            ending_floor_uvalue = get_floor_u_value(
+                floor_type=floor_type,
+                perimeter=perimeters["estimated_perimeter_ENDING"],
+                area=x[f"TOTAL_FLOOR_AREA_ENDING"],
+                insulation_thickness=extract_insulation_thickness(x["floor_insulation_thickness_ENDING"]),
+                wall_type=wall_type,
+                age_band=age_band
+            )
 
         uvalues.append(
             {
@@ -290,6 +326,9 @@ def make_uvalues(df):
                 "ending_wall_uvalue": ending_wall_uvalue,
                 "starting_roof_uvalue": starting_roof_uvalue,
                 "ending_roof_uvalue": ending_roof_uvalue,
+                "starting_floor_uvalue": starting_floor_uvalue,
+                "ending_floor_uvalue": ending_floor_uvalue,
+                **perimeters
             }
         )
 
@@ -454,13 +493,6 @@ def app():
             columns=["walls_clean_description", "walls_clean_description_ENDING"]
         )
 
-
-
-
-
-
-        get_wall_u_value(clean_description=)
-
         if pd.isnull(data_by_urpn_df).sum().sum():
             raise ValueError("Null values found in dataset after process_and_prune_desriptions")
 
diff --git a/recommendations/rdsap_tables.py b/recommendations/rdsap_tables.py
index 748d4034..6abbea8b 100644
--- a/recommendations/rdsap_tables.py
+++ b/recommendations/rdsap_tables.py
@@ -438,6 +438,8 @@ table_s10 = pd.DataFrame(s10_list)
 # Table s11 is used for assigning the u-values of floors when the insulation thickness is unknown
 # which can be found on page 25 of the BRE document
 # https://bregroup.com/wp-content/uploads/2019/09/RdSAP_2012_9.94-20-09-2019.pdf
+#
+# The thickness values are in mm
 ########################################################################################################################
 
 s11_list = [
@@ -446,17 +448,17 @@ s11_list = [
     {"Age_band": "C to F", "Floor_construction": "solid", "England_Wales": 0, "Scotland": 0,
      "Northern_Ireland": 0, "Park_home": 0},
     {"Age_band": "G", "Floor_construction": "solid", "England_Wales": 0, "Scotland": 0,
-     "Northern_Ireland": 0, "Park_home": "25"},
-    {"Age_band": "H", "Floor_construction": "solid", "England_Wales": 0, "Scotland": "25",
-     "Northern_Ireland": "25", "Park_home": 0},
-    {"Age_band": "I", "Floor_construction": "solid", "England_Wales": "25", "Scotland": "50",
-     "Northern_Ireland": "50", "Park_home": "50"},
-    {"Age_band": "J", "Floor_construction": "solid", "England_Wales": "75", "Scotland": "75",
+     "Northern_Ireland": 0, "Park_home": 25},
+    {"Age_band": "H", "Floor_construction": "solid", "England_Wales": 0, "Scotland": 25,
+     "Northern_Ireland": 25, "Park_home": 0},
+    {"Age_band": "I", "Floor_construction": "solid", "England_Wales": 25, "Scotland": 50,
+     "Northern_Ireland": 50, "Park_home": 50},
+    {"Age_band": "J", "Floor_construction": "solid", "England_Wales": 75, "Scotland": 75,
      "Northern_Ireland": 0, "Park_home": 0},
-    {"Age_band": "K", "Floor_construction": "solid", "England_Wales": "100", "Scotland": "100",
-     "Northern_Ireland": "100", "Park_home": "70"},
-    {"Age_band": "L", "Floor_construction": "solid", "England_Wales": "100", "Scotland": "120",
-     "Northern_Ireland": "100", "Park_home": 0},
+    {"Age_band": "K", "Floor_construction": "solid", "England_Wales": 100, "Scotland": 100,
+     "Northern_Ireland": 100, "Park_home": 70},
+    {"Age_band": "L", "Floor_construction": "solid", "England_Wales": 100, "Scotland": 120,
+     "Northern_Ireland": 100, "Park_home": 0},
 ]
 
 table_s11 = pd.DataFrame(s11_list)
diff --git a/recommendations/recommendation_utils.py b/recommendations/recommendation_utils.py
index d1d90de9..9ffab939 100644
--- a/recommendations/recommendation_utils.py
+++ b/recommendations/recommendation_utils.py
@@ -369,7 +369,7 @@ def estimate_perimeter_2_rooms(floor_area):
     return perimeter
 
 
-def calculate_floor_u_value(floor_type, area, perimeter, age_band, wall_type, insulation_thickness=None):
+def get_floor_u_value(floor_type, area, perimeter, age_band, wall_type, insulation_thickness=None):
     """
     Estimate the u-value of a suspended floor, based on RdSap methodology
     Default U-value for UNINSULATED suspended floor, based on RdSAP methodology
@@ -458,3 +458,52 @@ def calculate_floor_u_value(floor_type, area, perimeter, age_band, wall_type, in
         raise ValueError("Invalid floor type. Acceptable values are 'solid' or 'suspended'.")
 
     return round(U, 2)  # rounding U value to two decimal places
+
+
+def extract_insulation_thickness(insulation_thickness_str):
+    """
+    Converts insulation thickness to a float
+    :param insulation_thickness_str:
+    :return:
+    """
+    if insulation_thickness_str == "none":
+        return 0
+
+    return int(insulation_thickness_str.replace("mm", ""))
+
+
+def get_wall_type(
+    is_cavity_wall,
+    is_solid_brick,
+    is_granite_or_whinstone,
+    is_sandstone_or_limestone,
+    is_timber_frame,
+    is_cob,
+    is_system_built,
+    is_park_home,
+    **kwargs
+):
+    """
+    Converts booleans to a string wall type, for querying the wall thickness table
+    :return:
+    """
+    if is_cavity_wall:
+        return "cavity"
+
+    if is_solid_brick:
+        return "solid brick"
+
+    if is_granite_or_whinstone or is_sandstone_or_limestone:
+        return "stone"
+
+    if is_timber_frame:
+        return "timber frame"
+
+    if is_cob:
+        return "cob"
+
+    if is_system_built:
+        return "system build"
+
+    if is_park_home:
+        return "park home"