diff --git a/include/internal/catch_result_builder.h b/include/internal/catch_result_builder.h
index 8249456..b1808cc 100644
--- a/include/internal/catch_result_builder.h
+++ b/include/internal/catch_result_builder.h
@@ -47,7 +47,7 @@ namespace Catch {
 
         template<typename T>
         ResultBuilder& operator << ( T const& value ) {
-            m_stream.oss << value;
+            m_stream().oss << value;
             return *this;
         }
 
@@ -80,7 +80,12 @@ namespace Catch {
     private:
         AssertionInfo m_assertionInfo;
         AssertionResultData m_data;
-        CopyableStream m_stream;
+
+        static CopyableStream &m_stream()
+        {
+            static CopyableStream s;
+            return s;
+        }
 
         bool m_shouldDebugBreak;
         bool m_shouldThrow;
diff --git a/include/internal/catch_result_builder.hpp b/include/internal/catch_result_builder.hpp
index 510fbc3..2abb9a9 100644
--- a/include/internal/catch_result_builder.hpp
+++ b/include/internal/catch_result_builder.hpp
@@ -27,12 +27,14 @@ namespace Catch {
         m_shouldDebugBreak( false ),
         m_shouldThrow( false ),
         m_guardException( false )
-    {}
+    {
+        m_stream().oss.str("");
+    }
 
     ResultBuilder::~ResultBuilder() {
 #if defined(CATCH_CONFIG_FAST_COMPILE)
         if ( m_guardException ) {
-            m_stream.oss << "Exception translation was disabled by CATCH_CONFIG_FAST_COMPILE";
+            m_stream().oss << "Exception translation was disabled by CATCH_CONFIG_FAST_COMPILE";
             captureResult( ResultWas::ThrewException );
             getCurrentContext().getResultCapture()->exceptionEarlyReported();
         }
@@ -55,7 +57,7 @@ namespace Catch {
 
     void ResultBuilder::useActiveException( ResultDisposition::Flags resultDisposition ) {
         m_assertionInfo.resultDisposition = resultDisposition;
-        m_stream.oss << Catch::translateActiveException();
+        m_stream().oss << Catch::translateActiveException();
         captureResult( ResultWas::ThrewException );
     }
 
@@ -143,7 +145,7 @@ namespace Catch {
             data.negate( expr.isBinaryExpression() );
         }
 
-        data.message = m_stream.oss.str();
+        data.message = m_stream().oss.str();
         data.decomposedExpression = &expr; // for lazy reconstruction
         return AssertionResult( m_assertionInfo, data );
     }