diff --git a/oslo_messaging/conffixture.py b/oslo_messaging/conffixture.py
index 0d05a5881..bb037b8db 100644
--- a/oslo_messaging/conffixture.py
+++ b/oslo_messaging/conffixture.py
@@ -128,7 +128,7 @@ class ConfFixture(fixtures.Fixture):
 
     @transport_driver.setter
     def transport_driver(self, value):
-        self.conf.set_override('rpc_backend', value)
+        self.conf.set_override('rpc_backend', value, enforce_type=True)
 
     @property
     def response_timeout(self):
@@ -137,4 +137,5 @@ class ConfFixture(fixtures.Fixture):
 
     @response_timeout.setter
     def response_timeout(self, value):
-        self.conf.set_override('rpc_response_timeout', value)
+        self.conf.set_override('rpc_response_timeout', value,
+                               enforce_type=True)
diff --git a/oslo_messaging/tests/rpc/test_client.py b/oslo_messaging/tests/rpc/test_client.py
index c5b7364d8..ebb72324b 100644
--- a/oslo_messaging/tests/rpc/test_client.py
+++ b/oslo_messaging/tests/rpc/test_client.py
@@ -221,7 +221,7 @@ class TestCallTimeout(test_utils.BaseTestCase):
         ('all_none',
          dict(confval=None, ctor=None, prepare=_notset, expect=None)),
         ('confval',
-         dict(confval=21.1, ctor=None, prepare=_notset, expect=21.1)),
+         dict(confval=21, ctor=None, prepare=_notset, expect=21)),
         ('ctor',
          dict(confval=None, ctor=21.1, prepare=_notset, expect=21.1)),
         ('ctor_zero',
diff --git a/oslo_messaging/tests/utils.py b/oslo_messaging/tests/utils.py
index eacfaedc8..aa2a56343 100644
--- a/oslo_messaging/tests/utils.py
+++ b/oslo_messaging/tests/utils.py
@@ -57,7 +57,7 @@ class BaseTestCase(base.BaseTestCase):
         """
         group = kw.pop('group', None)
         for k, v in six.iteritems(kw):
-            self.conf.set_override(k, v, group)
+            self.conf.set_override(k, v, group, enforce_type=True)
 
 
 class ServerThreadHelper(threading.Thread):