diff --git a/src/vt/vrt/collection/balance/model/weighted_messages.h b/src/vt/vrt/collection/balance/model/weighted_messages.h
index daadcf2533..68afc12399 100644
--- a/src/vt/vrt/collection/balance/model/weighted_messages.h
+++ b/src/vt/vrt/collection/balance/model/weighted_messages.h
@@ -59,7 +59,7 @@ struct WeightedMessages : public ComposedModel {
    */
   explicit WeightedMessages(
     std::shared_ptr<balance::LoadModel> base,
-    TimeType in_per_msg_weight, TimeType in_per_byte_weight
+    TimeType in_per_msg_weight = 0.0, TimeType in_per_byte_weight = 1.0
   ) : ComposedModel(base),
       per_msg_weight_(in_per_msg_weight),
       per_byte_weight_(in_per_byte_weight) { }
@@ -78,8 +78,8 @@ struct WeightedMessages : public ComposedModel {
   // observer pointer to the underlying comm data
   std::unordered_map<PhaseType, CommMapType> const* proc_comm_;
 
-  TimeType per_msg_weight_  = 0.0;
-  TimeType per_byte_weight_ = 1.0;
+  TimeType per_msg_weight_;
+  TimeType per_byte_weight_;
 };
 
 }}}} // namespace vt::vrt::collection::balance