diff --git a/datatypes/epc/domain/tests/test_from_site_notes.py b/datatypes/epc/domain/tests/test_from_site_notes.py
index d5dc35ffc..0b19b4084 100644
--- a/datatypes/epc/domain/tests/test_from_site_notes.py
+++ b/datatypes/epc/domain/tests/test_from_site_notes.py
@@ -1223,6 +1223,7 @@ class TestGlazingTypeCoding:
         [
             ("Double glazing installed before 2002", 3),  # double pre-2002, U 2.8
             ("Double glazing installed between 2002 - 2021", 2),  # double 2002-2022, U 2.0
+            ("Triple glazing installed between 2002 - 2021", 9),  # triple 2002-2022, U 2.0
             ("Double glazing, Unknown install date", 3),  # unknown → pre-2002 default, U 2.8
             ("Double glazing installed during or after 2022", 13),  # double 2022+, U 1.4
             ("", ""),  # no lodging — passes through (calc nulls it)