diff --git a/synfig-core/src/synfig/rendering/resource.cpp b/synfig-core/src/synfig/rendering/resource.cpp
index 11c09f5..3c03a98 100644
--- a/synfig-core/src/synfig/rendering/resource.cpp
+++ b/synfig-core/src/synfig/rendering/resource.cpp
@@ -46,7 +46,7 @@ using namespace rendering;
 
 Resource::Id Resource::last_id = 0;
 
-Resource::Storage::Storage(): refcount() { }
+Resource::Storage::Storage(): refcount(0) { }
 
 Resource::Storage::~Storage() { }
 
diff --git a/synfig-core/src/synfig/rendering/resource.h b/synfig-core/src/synfig/rendering/resource.h
index 283e9fc..cfb226c 100644
--- a/synfig-core/src/synfig/rendering/resource.h
+++ b/synfig-core/src/synfig/rendering/resource.h
@@ -62,7 +62,7 @@ public:
 		typedef etl::handle<Storage> Handle;
 
 	private:
-		mutable int refcount;
+		mutable std::atomic<int> refcount;
 
 		friend class Resource;