diff --git a/etl/join_building_data/load_conservation_areas.py b/etl/join_building_data/load_conservation_areas.py
new file mode 100644
index 00000000..cd84c595
--- /dev/null
+++ b/etl/join_building_data/load_conservation_areas.py
@@ -0,0 +1,77 @@
+"""Load CSV data to API
+
+This is effectively an example script using the HTTP API, tailored to particular collected
+datasets for conservation areas around London.
+
+Preprocess to filter down to unique buildings:
+
+    head -n 1 file.csv > file.uniq.csv
+    cat file.csv | \
+        cut -d "," -f 1,2 --complement | \
+        sort -n | \
+        uniq >> file.uniq.csv
+
+Then with this script:
+- read through CSV file, where entries have been pre-matched to building_id
+- update building with data
+
+
+"""
+import json
+import csv
+import os
+import subprocess
+import sys
+
+import requests
+from tqdm import tqdm
+
+
+def main(base_url, api_key, source_file):
+    """Read from file, update buildings
+    """
+    with open(source_file, 'r') as source_fh:
+        source = csv.DictReader(source_fh)
+        for feature in tqdm(source, total=line_count(source_file)):
+            building_id, data = process_ca(feature)
+            if building_id and building_id != 'building_id':
+                save_data(building_id, data, api_key, base_url)
+
+
+def line_count(fname):
+    """Count lines - relies on 'wc'
+    """
+    p = subprocess.run(['wc', '-l', fname], stdout=subprocess.PIPE)
+    if p.returncode != 0:
+        raise IOError(err)
+    return int(p.stdout.strip().split()[0])
+
+def process_ca(props):
+    building_id = props['building_id']
+    data = {
+        'planning_in_conservation_area': True,
+        'planning_conservation_area_name': props['conservation_area_name']
+    }
+    return building_id, data
+
+
+def save_data(building_id, data, api_key, base_url):
+    """Save data to a building
+    """
+    r = requests.post(
+        "{}/building/{}.json?api_key={}".format(base_url, building_id, api_key),
+        json=data
+    )
+
+
+if __name__ == '__main__':
+    try:
+        url, api_key, filename = sys.argv[1], sys.argv[2], sys.argv[3]
+    except IndexError:
+        print(
+            "Usage: {} <URL> <api_key> ./path/to/conservation_areas.csv".format(
+            os.path.basename(__file__)
+        ))
+        exit()
+
+    main(url, api_key, filename)