diff --git a/env/rhel7/x86_64/admin/stable/spack.yaml b/env/rhel7/x86_64/admin/stable/spack.yaml
index 8ff4145..909c47b 100644
--- a/env/rhel7/x86_64/admin/stable/spack.yaml
+++ b/env/rhel7/x86_64/admin/stable/spack.yaml
@@ -12,6 +12,10 @@ spack:
   - $spack/spack-psi/env/rhel7/$target_family/sysconfigs/compilers.yaml
   mirrors:
     local_psi: file:///afs/psi.ch/software/spack/testing
+  modules:
+    default:
+      roots:
+        tcl: $spack/opt/spack/stable/modulefiles
   specs:
   - matrix:
     - [$gcc_12.3.0_openmpi]
diff --git a/env/rhel7/x86_64/admin/testing/spack.yaml b/env/rhel7/x86_64/admin/testing/spack.yaml
index 8389b9b..da216f7 100644
--- a/env/rhel7/x86_64/admin/testing/spack.yaml
+++ b/env/rhel7/x86_64/admin/testing/spack.yaml
@@ -12,5 +12,9 @@ spack:
     - $spack/spack-psi/env/rhel7/$target_family/sysconfigs/compilers.yaml
   mirrors:
     local_psi: file:///afs/psi.ch/software/spack/testing
+  modules:
+    default:
+      roots:
+        tcl: $spack/opt/spack/testing/modulefiles
   specs: []
   view: false
diff --git a/env/rhel7/x86_64/admin/unstable/spack.yaml b/env/rhel7/x86_64/admin/unstable/spack.yaml
index b0d9722..7af5989 100644
--- a/env/rhel7/x86_64/admin/unstable/spack.yaml
+++ b/env/rhel7/x86_64/admin/unstable/spack.yaml
@@ -26,6 +26,10 @@ spack:
     - $spack/spack-psi/env/rhel7/$target_family/sysconfigs/compilers.yaml
   mirrors:
     local_psi: file:///afs/psi.ch/software/spack/testing
+  modules:
+    default:
+      roots:
+        tcl: $spack/opt/spack/unstable/modulefiles
   specs:
   - matrix:
     - [$gcc_12.3.0]
diff --git a/env/sles15/x86_64/admin/testing/spack.yaml b/env/sles15/x86_64/admin/testing/spack.yaml
index 9fe5ea8..ea17d6d 100644
--- a/env/sles15/x86_64/admin/testing/spack.yaml
+++ b/env/sles15/x86_64/admin/testing/spack.yaml
@@ -9,5 +9,9 @@ spack:
   - $spack/spack-psi/env/$os/$target_family/sysconfigs/compilers.yaml
   mirrors:
     local_psi: file:///afs/psi.ch/software/spack/testing
+  modules:
+    default:
+      roots:
+        tcl: $spack/opt/spack/testing/modulefiles
   specs: []
   view: false