diff --git a/unit_tests/test_zaza_charm_lifecycle_deploy.py b/unit_tests/test_zaza_charm_lifecycle_deploy.py
index 235f6be..a547cad 100644
--- a/unit_tests/test_zaza_charm_lifecycle_deploy.py
+++ b/unit_tests/test_zaza_charm_lifecycle_deploy.py
@@ -118,6 +118,33 @@ class TestCharmLifecycleDeploy(ut_utils.BaseTestCase):
         self.get_template.return_value = None
         self.assertIsNone(lc_deploy.render_overlay('mybundle.yaml', '/tmp/'))
 
+    def test_render_local_overlay(self):
+        self.patch_object(lc_deploy.jinja2, 'Environment')
+        self.patch_object(lc_deploy, 'get_template', return_value='atemplate')
+        self.patch_object(lc_deploy, 'render_template')
+        self.assertEqual(
+            lc_deploy.render_local_overlay('/target'),
+            '/target/local-charm-overlay.yaml')
+        self.assertFalse(self.Environment.called)
+        self.render_template.assert_called_once_with(
+            'atemplate',
+            '/target/local-charm-overlay.yaml')
+
+    def test_render_local_overlay_default(self):
+        jenv_mock = mock.MagicMock()
+        jenv_mock.from_string.return_value = 'atemplate'
+        self.patch_object(lc_deploy.jinja2, 'Environment',
+                          return_value=jenv_mock)
+        self.patch_object(lc_deploy, 'get_template', return_value=None)
+        self.patch_object(lc_deploy, 'render_template')
+        self.assertEqual(
+            lc_deploy.render_local_overlay('/target'),
+            '/target/local-charm-overlay.yaml')
+        jenv_mock.from_string.assert_called_once_with(mock.ANY)
+        self.render_template.assert_called_once_with(
+            'atemplate',
+            '/target/local-charm-overlay.yaml')
+
     def test_render_overlays(self):
         RESP = {
             'mybundles/mybundle.yaml': '/tmp/mybundle.yaml'}
diff --git a/zaza/charm_lifecycle/deploy.py b/zaza/charm_lifecycle/deploy.py
index 7a72f7c..96ae68d 100755
--- a/zaza/charm_lifecycle/deploy.py
+++ b/zaza/charm_lifecycle/deploy.py
@@ -24,6 +24,7 @@ applications:
   {{ charm_name }}:
     charm: {{ charm_location }}
 """
+LOCAL_OVERLAY_TEMPLATE_NAME = 'local-charm-overlay.yaml'
 
 
 def is_valid_env_key(key):
@@ -169,11 +170,13 @@ def render_local_overlay(target_dir):
     :returns: Path to rendered overlay
     :rtype: str
     """
-    template = jinja2.Environment(loader=jinja2.BaseLoader).from_string(
-        LOCAL_OVERLAY_TEMPLATE)
+    template = get_template(LOCAL_OVERLAY_TEMPLATE_NAME)
+    if not template:
+        template = jinja2.Environment(loader=jinja2.BaseLoader).from_string(
+            LOCAL_OVERLAY_TEMPLATE)
     rendered_template_file = os.path.join(
         target_dir,
-        os.path.basename('local-charm-overlay.yaml'))
+        os.path.basename(LOCAL_OVERLAY_TEMPLATE_NAME))
     render_template(template, rendered_template_file)
     return rendered_template_file