diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7124548c39..82ce102756 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -145,11 +145,7 @@ endif()
 #########################################################
 # Base directories, compatible with legacy OAI building #
 #########################################################
-set (OPENAIR_DIR     $ENV{OPENAIR_DIR})
-if("${OPENAIR_DIR}" STREQUAL "")
-  string(REGEX REPLACE "/cmake_targets.*$" "" OPENAIR_DIR ${CMAKE_CURRENT_BINARY_DIR})
-endif()
-
+set (OPENAIR_DIR     ${CMAKE_SOURCE_DIR})
 set (NFAPI_DIR       ${OPENAIR_DIR}/nfapi/open-nFAPI)
 set (NFAPI_USER_DIR  ${OPENAIR_DIR}/nfapi/oai_integration)
 set (OPENAIR1_DIR    ${OPENAIR_DIR}/openair1)