diff --git a/apps/opencs/model/world/data.cpp b/apps/opencs/model/world/data.cpp
index 09296b55d6..a6268c1a48 100644
--- a/apps/opencs/model/world/data.cpp
+++ b/apps/opencs/model/world/data.cpp
@@ -1209,9 +1209,8 @@ bool CSMWorld::Data::continueLoading(CSMDoc::Messages& messages)
                 messages.add(id, "Logic error: cell index out of bounds", "", CSMDoc::Message::Severity_Error);
                 index = mCells.getSize() - 1;
             }
-            const std::string cellId = mCells.getId(index).getRefIdString();
 
-            mRefs.load(*mReader, index, mBase, mRefLoadCache[cellId], messages);
+            mRefs.load(*mReader, index, mBase, mRefLoadCache[mCells.getId(index)], messages);
             break;
         }
 
diff --git a/apps/opencs/model/world/data.hpp b/apps/opencs/model/world/data.hpp
index 6db992cca6..42c5309723 100644
--- a/apps/opencs/model/world/data.hpp
+++ b/apps/opencs/model/world/data.hpp
@@ -123,7 +123,7 @@ namespace CSMWorld
         const ESM::Dialogue* mDialogue; // last loaded dialogue
         bool mBase;
         bool mProject;
-        std::map<std::string, std::map<unsigned int, unsigned int>, Misc::StringUtils::CiComp> mRefLoadCache;
+        std::map<ESM::RefId, std::map<unsigned int, unsigned int>> mRefLoadCache;
         int mReaderIndex;
 
         bool mFsStrict;