diff --git a/plexapi/library.py b/plexapi/library.py
index f62d5913..5afff962 100644
--- a/plexapi/library.py
+++ b/plexapi/library.py
@@ -356,6 +356,9 @@ class LibrarySection(PlexObject):
         self._filterTypes = None
         self._fieldTypes = None
         self._totalViewSize = None
+        self._totalSize = None
+        self._totalDuration = None
+        self._totalStorage = None
 
     def fetchItems(self, ekey, cls=None, container_start=None, container_size=None, **kwargs):
         """ Load the specified key to find and build all items with the specified tag
@@ -394,7 +397,36 @@ class LibrarySection(PlexObject):
     @property
     def totalSize(self):
         """ Returns the total number of items in the library for the default library type. """
-        return self.totalViewSize(includeCollections=False)
+        if self._totalSize is None:
+            self._totalSize = self.totalViewSize(includeCollections=False)
+        return self._totalSize
+
+    @property
+    def totalDuration(self):
+        """ Returns the total duration (in milliseconds) of items in the library. """
+        if self._totalDuration is None:
+            self._getTotalDurationStorage()
+        return self._totalDuration
+
+    @property
+    def totalStorage(self):
+        """ Returns the total storage (in bytes) of items in the library. """
+        if self._totalStorage is None:
+            self._getTotalDurationStorage()
+        return self._totalStorage
+
+    def _getTotalDurationStorage(self):
+        """ Queries the Plex server for the total library duration and storage and caches the values. """
+        data = self._server.query('/media/providers?includeStorage=1')
+        xpath = (
+            './MediaProvider[@identifier="com.plexapp.plugins.library"]'
+            '/Feature[@type="content"]'
+            '/Directory[@id="%s"]'
+        ) % self.key
+        directory = next(iter(data.findall(xpath)), None)
+        if directory:
+            self._totalDuration = utils.cast(int, directory.attrib.get('durationTotal'))
+            self._totalStorage = utils.cast(int, directory.attrib.get('storageTotal'))
 
     def totalViewSize(self, libtype=None, includeCollections=True):
         """ Returns the total number of items in the library for a specified libtype.
diff --git a/tests/test_library.py b/tests/test_library.py
index a6360279..da2bb015 100644
--- a/tests/test_library.py
+++ b/tests/test_library.py
@@ -61,7 +61,6 @@ def test_library_MovieSection_getGuid(movies, movie):
 
 
 def test_library_section_movies_all(movies):
-    # size should always be none unless pagenation is being used.
     assert movies.totalSize == 4
     assert len(movies.all(container_start=0, container_size=1, maxresults=1)) == 1
 
@@ -79,6 +78,14 @@ def test_library_section_movies_all_guids(movies):
         plexapi.base.USER_DONT_RELOAD_FOR_KEYS.remove('guids')
 
 
+def test_library_section_totalDuration(tvshows):
+    assert utils.is_int(tvshows.totalDuration)
+
+
+def test_library_section_totalStorage(tvshows):
+    assert utils.is_int(tvshows.totalStorage)
+
+
 def test_library_section_totalViewSize(tvshows):
     assert tvshows.totalViewSize() == 2
     assert tvshows.totalViewSize(libtype="show") == 2