diff --git a/addons/mission/XEH_PREP.hpp b/addons/mission/XEH_PREP.hpp
index e9274159..a2d05bf5 100644
--- a/addons/mission/XEH_PREP.hpp
+++ b/addons/mission/XEH_PREP.hpp
@@ -22,6 +22,7 @@ PREP(enableAI);
 PREP(forceShooting);
 PREP(groundFog);
 PREP(jam);
+PREP(lockDoors);
 PREP(markBuildings);
 PREP(mortarStrike);
 PREP(ping);
diff --git a/addons/mission/functions/fnc_lockDoors.sqf b/addons/mission/functions/fnc_lockDoors.sqf
new file mode 100644
index 00000000..74a01015
--- /dev/null
+++ b/addons/mission/functions/fnc_lockDoors.sqf
@@ -0,0 +1,39 @@
+#include "..\script_component.hpp"
+/*
+ * Author: Mike
+ *
+ * Call on the server with isGlobal flag or locally without it.
+ *
+ * Arguments:
+ * 0: Building <OBJECT>
+ * 1: Door Index <ARRAY> (default: [])
+ * 2: Lock State <NUMBER> (default: 1)
+ * 2: Global <BOOL> (default: true)
+ *
+ * Return Value:
+ * None
+ *
+ * Examples:
+ * [My_Building, [1, 2]] call MFUNC(lockDoors);
+ * [My_Building, [1, 2, 3, 4], 0, false] call MFUNC(lockDoors);
+*/
+
+params ["_building", ["_doorIndex", []], ["_lockState", 1], ["_isGlobal", true]];
+
+// If running globally, exit if not the server.
+if (_isGlobal && !isServer) exitWith {};
+
+// Exit if door index array is empty
+if (_doorIndex isEqualTo []) exitWith {
+    ERROR_MSG("Door Index is empty.");
+};
+
+// Check lockstate value is correct.
+if !(_lockState in [0, 1]) exitWith {
+    ERROR_MSG_1("Lock State is invalid (%1), expected 0 or 1.",_lockState);
+};
+
+{
+    private _door = format ["BIS_Disabled_Door_%1", _x];
+    _building setVariable [_door, _lockState, _isGlobal];
+} forEach _doorIndex;