diff --git a/heat/engine/checkeddict.py b/heat/engine/checkeddict.py
index a2b6d55750..0a0cdb0488 100644
--- a/heat/engine/checkeddict.py
+++ b/heat/engine/checkeddict.py
@@ -135,9 +135,11 @@ class Properties(CheckedDict):
     def validate(self):
         for key in self.data:
             # are there missing required Properties
-            if 'Required' in self.data[key] and not 'Value' in self.data[key]:
-                return {'Error': \
-                    '%s Property must be provided' % key}
+            if 'Required' in self.data[key]:
+                if self.data[key]['Required'] \
+                    and not 'Value' in self.data[key]:
+                    return {'Error': \
+                        '%s Property must be provided' % key}
 
             # are there unimplemented Properties
             if not self.data[key]['Implemented'] and 'Value' in self.data[key]:
diff --git a/heat/engine/security_group.py b/heat/engine/security_group.py
index 43083facbe..82a463ecdb 100644
--- a/heat/engine/security_group.py
+++ b/heat/engine/security_group.py
@@ -29,9 +29,9 @@ class SecurityGroup(Resource):
                                               'Required': True},
                          'VpcId': {'Type': 'String',
                                    'Implemented': False},
-                         'SecurityGroupIngress': {'Type': 'CommaDelimitedList',
+                         'SecurityGroupIngress': {'Type': 'TuplesList',
                                                   'Implemented': False},
-                         'SecurityGroupEgress': {'Type': 'CommaDelimitedList'}}
+                         'SecurityGroupEgress': {'Type': 'TuplesList'}}
 
     def __init__(self, name, json_snippet, stack):
         super(SecurityGroup, self).__init__(name, json_snippet, stack)
diff --git a/heat/engine/volume.py b/heat/engine/volume.py
index b506ce218c..df49b20edd 100644
--- a/heat/engine/volume.py
+++ b/heat/engine/volume.py
@@ -28,7 +28,8 @@ class Volume(Resource):
     properties_schema = {'AvailabilityZone': {'Type': 'String',
                                               'Required': True},
                          'Size': {'Type': 'Number'},
-                         'SnapshotId': {'Type': 'String'}}
+                         'SnapshotId': {'Type': 'String'},
+                         'Tags': {'Type': 'TuplesList'}}
 
     def __init__(self, name, json_snippet, stack):
         super(Volume, self).__init__(name, json_snippet, stack)