diff --git a/heaptrack.spec b/heaptrack.spec
index bd90dfd..3695941 100644
--- a/heaptrack.spec
+++ b/heaptrack.spec
@@ -85,8 +85,13 @@ A Qt5/KF5 based GUI for Heaptrack.
 # Disable building tests, they're not used and post-build-checks trips over it
 sed -i"" '/add_subdirectory(tests)/d' CMakeLists.txt
 
+extra_options=""
+%if "%{?_lib}" == "lib64"
+extra_options="-DLIB_SUFFIX=64"
+%endif
+
 %build
-  %cmake_kf5 -d build -- -DLIB_INSTALL_DIR=%{_libdir}
+  %cmake_kf5 -d build -- $extra_options
   %cmake_build
 
 %install