diff --git a/domain/sap10_calculator/rdsap/cert_to_inputs.py b/domain/sap10_calculator/rdsap/cert_to_inputs.py
index 469223ab..0ea700e8 100644
--- a/domain/sap10_calculator/rdsap/cert_to_inputs.py
+++ b/domain/sap10_calculator/rdsap/cert_to_inputs.py
@@ -995,6 +995,8 @@ _SECONDARY_HEATING_FRACTION_BY_CATEGORY: Final[dict[int, float]] = {
                # p.188). Cert 0380 (warm air mains gas, code 506, +
                # electric room-heater secondary) raised here before.
     10: 0.20,
+    11: 0.10,   # Electric ceiling heating (SAP code 701): direct-acting
+                # electric, SAP 10.2 Table 11 "Other electric systems" row.
 }
 _SECONDARY_HEATING_FRACTION_DEFAULT: Final[float] = 0.10