diff --git a/index.html b/index.html
index 282b4fc6..bb320c7a 100644
--- a/index.html
+++ b/index.html
@@ -63,7 +63,6 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
       /**
       * [polymer-root-path]
       *
-      * By default, we set `Polymer.rootPath` to the server root path (`/`).
       * Leave this line unchanged if you intend to serve your app from the root
       * path (e.g., with URLs like `my.domain/` and `my.domain/view1`).
       *
@@ -72,13 +71,13 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
       * to indicate the path from which you'll be serving, including leading
       * and trailing slashes (e.g., `/my-app/`).
       */
-      window.Polymer = { rootPath: '/' };
+      window.MyAppGlobals = { rootPath: '/' };
 
       // Load and register pre-caching Service Worker
       if ('serviceWorker' in navigator) {
         window.addEventListener('load', function() {
           navigator.serviceWorker.register('service-worker.js', {
-            scope: Polymer.rootPath
+            scope: MyAppGlobals.rootPath
           });
         });
       }
diff --git a/src/my-app.js b/src/my-app.js
index c8dee8b0..ca79032b 100644
--- a/src/my-app.js
+++ b/src/my-app.js
@@ -27,7 +27,9 @@ import './my-icons.js';
 // preventable, allowing for better scrolling performance.
 setPassiveTouchGestures(true);
 
-setRootPath(Polymer.rootPath);
+// Set Polymer's root path to the same value we passed to our service worker
+// in `index.html`.
+setRootPath(MyAppGlobals.rootPath);
 
 class MyApp extends PolymerElement {
   static get template() {