diff --git a/include/rexy/string_base.tpp b/include/rexy/string_base.tpp
index 97c038f..e948688 100644
--- a/include/rexy/string_base.tpp
+++ b/include/rexy/string_base.tpp
@@ -175,7 +175,8 @@ namespace rexy{
 			m_data[m_length] = 0;
 		}else if(!m_data){
 			*this = string_intermediary(len, len);
-			memcpy(m_data, data, len+1);
+			memcpy(m_data, data, len);
+			m_data[len] = 0;
 		}else{
 			auto newsize = cx::max(m_length+len, m_cap*2);
 			string_intermediary tmp(newsize);