diff --git a/make.bat b/make.bat
index fa71760..fcf2107 100644
--- a/make.bat
+++ b/make.bat
@@ -7,8 +7,10 @@ REM Command file for Sphinx documentation
 if "%SPHINXBUILD%" == "" (
 	set SPHINXBUILD=sphinx-build
 )
+if "%BUILDDIR%" == "" (
+	set SPHINXBUILD=build
+)
 set SOURCEDIR=src
-set BUILDDIR=build
 
 if "%1" == "" goto help