diff --git a/avogadro.spec b/avogadro.spec
index e17b0f2..0ec823f 100644
--- a/avogadro.spec
+++ b/avogadro.spec
@@ -1,5 +1,7 @@
 # Avogadro supports Python2 only
 
+%global __cmake_in_source_build 1
+
 %undefine _ld_as_needed
 
 Name:           avogadro