diff --git a/nodepool/builder.py b/nodepool/builder.py
index 06c82d469..76013e77d 100644
--- a/nodepool/builder.py
+++ b/nodepool/builder.py
@@ -221,27 +221,26 @@ class CleanupWorker(BaseWorker):
             if e.errno != 2:    # No such file or directory
                 raise e
 
-    def _deleteLocalBuild(self, image, build_id, builder):
+    def _deleteLocalBuild(self, image, build):
         '''
         Remove expired image build from local disk.
 
         :param str image: Name of the image whose build we are deleting.
-        :param str build_id: ID of the build we want to delete.
-        :param str builder: hostname of the build.
+        :param ImageBuild build: The build we want to delete.
 
         :returns: True if files were deleted, False if none were found.
         '''
-        base = "-".join([image, build_id])
+        base = "-".join([image, build.id])
         files = DibImageFile.from_image_id(self._config.imagesdir, base)
         if not files:
             # NOTE(pabelanger): It is possible we don't have any files because
             # diskimage-builder failed. So, check to see if we have the correct
             # builder so we can removed the data from zookeeper.
-            if builder == self._hostname:
+            if build.builder == self._hostname:
                 return True
             return False
 
-        self.log.info("Doing cleanup for %s:%s" % (image, build_id))
+        self.log.info("Doing cleanup for %s:%s" % (image, build.id))
 
         manifest_dir = None
 
@@ -468,7 +467,7 @@ class CleanupWorker(BaseWorker):
                         self._zk.storeBuild(image, build, build.id)
 
                 # Release the lock here so we can delete the build znode
-                if self._deleteLocalBuild(image, build.id, build.builder):
+                if self._deleteLocalBuild(image, build):
                     if not self._zk.deleteBuild(image, build.id):
                         self.log.error("Unable to delete build %s because"
                                        " uploads still remain.", build)