diff --git a/setup.py b/setup.py
index f4bc5f45..1d1b3700 100644
--- a/setup.py
+++ b/setup.py
@@ -24,7 +24,7 @@ def initialize_options(self):
         # clashes with directories many developers have in their source trees;
         # this can create confusing results with "pip install .", which clones
         # the whole source tree by default
-        self.build_base = "_tmppythonbuild"
+        self.build_base = os.path.join("_tmppythonbuild", "amrex")
 
     def run(self):
         # remove existing build directory