diff --git a/source/blender/radiosity/intern/source/Makefile b/source/blender/radiosity/intern/source/Makefile
index 7040f17f448..fd2ff50ca41 100644
--- a/source/blender/radiosity/intern/source/Makefile
+++ b/source/blender/radiosity/intern/source/Makefile
@@ -56,4 +56,4 @@ CPPFLAGS += -I$(NAN_GUARDEDALLOC)/include
 # first /include is my own includes, second are the external includes
 # third is the external interface. there should be a nicer way to say this 
 CPPFLAGS += -I../include -I../../../include -I../../extern/include
-
+CPPFLAGS += -I../../../render/extern/include