diff --git a/var/spack/repos/builtin/packages/nut/package.py b/var/spack/repos/builtin/packages/nut/package.py
index 45eff1207a4a950933cdf0a52d5205882fc8d738..0cc637fbaa1377426dc16210ad2ebac252ac55f9 100644
--- a/var/spack/repos/builtin/packages/nut/package.py
+++ b/var/spack/repos/builtin/packages/nut/package.py
@@ -38,7 +38,7 @@ def install(self, spec, prefix):
         install('README.md', prefix)
         mkdirp(prefix.bin)
         mkdirp(prefix.lib)
-        install('../spack-build/apps/bh-3', prefix.bin)
-        install('../spack-build/lib/libnut.a', prefix.lib)
+        install(join_path(self.build_directory, 'apps/bh-3'), prefix.bin)
+        install(join_path(self.build_directory, 'lib/libnut.a'), prefix.lib)
         install_tree('test/data', prefix.data)
         install_tree('lib', prefix.include)