diff --git a/firebase-firestore-mixin.html b/firebase-firestore-mixin.html
index a7bcc07..f9ed87c 100644
--- a/firebase-firestore-mixin.html
+++ b/firebase-firestore-mixin.html
@@ -169,13 +169,15 @@
 
         this._firestoreProps = {};
         this._firestoreListeners = {};
-        this.db = this.constructor.db || firebase.firestore();
       }
 
       connectedCallback() {
         if (this[CONNECTED_CALLBACK_TOKEN] !== true) {
           this[CONNECTED_CALLBACK_TOKEN] = true;
 
+          this.db = this.constructor.db || firebase.firestore();
+          this.db.settings({timestampsInSnapshots: true});
+
           const props = collect(this.constructor, 'properties');
           Object
             .values(props)