diff --git a/src/lib/bind/accessors.html b/src/lib/bind/accessors.html
index 68f2b3355c..19af32507e 100644
--- a/src/lib/bind/accessors.html
+++ b/src/lib/bind/accessors.html
@@ -70,7 +70,7 @@
         var effects = node._propertyEffects && node._propertyEffects[property];
         if (effects) {
           node._propertySetter(property, value, effects, quiet);
-        } else {
+        } else if (node[property] !== value) {
           node[property] = value;
         }
       },
diff --git a/test/unit/bind.html b/test/unit/bind.html
index 9837496dc8..cfd92ee91e 100644
--- a/test/unit/bind.html
+++ b/test/unit/bind.html
@@ -869,6 +869,20 @@
     assert.isTrue(el._isAttachedChanged.calledOnce);
     document.body.removeChild(el);
   });
+
+  test('do not override property when going downwards', function() {
+    var value = 5, value_set_again = false, targetObj = {
+      get value () {
+        return value;
+      },
+      set value (v) {
+        value = v;
+        value_set_again = true;
+      }
+    };
+    Polymer.Bind._modelApi.__setProperty('value', 5, false, targetObj);
+    assert.isFalse(value_set_again);
+  });
 });
 
 suite('compound binding / string interpolation', function() {