diff --git a/build.sh b/build.sh
index b372168f98..f9c6beefed 100755
--- a/build.sh
+++ b/build.sh
@@ -228,7 +228,7 @@ do
       fi
     else
       begin_section "Build$variant"
-      build "$variant" "$build_dir" > "$build_log" 2>&1
+      build "$variant" "$build_dir" >> "$build_log" 2>&1
       begin_section Tests
       grep --line-buffered "^##teamcity" "$build_log"
       end_section Tests