diff --git a/source/common/engine/serializer.h b/source/common/engine/serializer.h
index 714c0d168..b4342ae6c 100644
--- a/source/common/engine/serializer.h
+++ b/source/common/engine/serializer.h
@@ -302,6 +302,11 @@ FSerializer& Serialize(FSerializer& arc, const char* key, FixedBitArray<size>& v
 	return arc.SerializeMemory(key, value.Storage(), value.StorageSize());
 }
 
+inline FSerializer& Serialize(FSerializer& arc, const char* key, BitArray& value, BitArray* def)
+{
+	return arc.SerializeMemory(key, value.Storage().Data(), value.Storage().Size());
+}
+
 template<> FSerializer& Serialize(FSerializer& arc, const char* key, PClass*& clst, PClass** def);
 template<> FSerializer& Serialize(FSerializer& arc, const char* key, FFont*& font, FFont** def);
 template<> FSerializer &Serialize(FSerializer &arc, const char *key, Dictionary *&dict, Dictionary **def);
diff --git a/source/core/automap.cpp b/source/core/automap.cpp
index e9eeb076b..d633121c2 100644
--- a/source/core/automap.cpp
+++ b/source/core/automap.cpp
@@ -267,9 +267,8 @@ void SerializeAutomap(FSerializer& arc)
 	{
 		arc("automapping", automapping)
 			("fullmap", gFullMap)
-			// Only store what's needed. Unfortunately for sprites it is not that easy
-			.SerializeMemory("mappedsectors", show2dsector.Storage().Data(), (numsectors + 7) / 8)
-			.SerializeMemory("mappedwalls", show2dwall.Storage().Data(), (numwalls + 7) / 8)
+			("mappedsectors", show2dsector)
+			("mappedwalls", show2dwall)
 			.EndObject();
 	}
 }