diff --git a/src/app/services/formulaire/formulaire.service.ts b/src/app/services/formulaire/formulaire.service.ts
index 7433bb6313fdaa5d40aaadf9c0743202e276d104..a7ba491b37217baac73dcbea389c99d8fdf28e61 100644
--- a/src/app/services/formulaire/formulaire.service.ts
+++ b/src/app/services/formulaire/formulaire.service.ts
@@ -334,8 +334,13 @@ export class FormulaireService extends Observable {
             }
 
             // when creating a new Pab, add one wall with one device, plus the downwall
-            // (when loading session only)
-            if (f instanceof FormulairePab && f.currentNub instanceof Pab) {
+            // (when loading session, those items are already present)
+            if (
+                f instanceof FormulairePab
+                && f.currentNub instanceof Pab
+                && f.currentNub.children.length === 0
+                && f.currentNub.downWall === undefined
+            ) {
                 // 1. one wall
                 const newWall = Session.getInstance().createNub(
                     new Props({