diff --git a/build-moose-core b/build-moose-core
index e97b1d28500493fff7c74e57c2dc6b0dbc19ff99..333601bf1c93a18667e6f638d499d408e2b6020e 100755
--- a/build-moose-core
+++ b/build-moose-core
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-(cd moose-core; make USE_SBML=1)
+(cd moose-core; make clean; make USE_SBML=1)
 local_site_package_directory=`python -c "import site; print site.getusersitepackages()"`
 mkdir -p "$local_site_package_directory"
 echo "`pwd`/moose-core/python" > "$local_site_package_directory/moose.pth"