diff --git a/app/src/modules/builder/wall/Instances/instance/helpers/useWallClassification.ts b/app/src/modules/builder/wall/Instances/instance/helpers/useWallClassification.ts
index 7451501..aaa3912 100644
--- a/app/src/modules/builder/wall/Instances/instance/helpers/useWallClassification.ts
+++ b/app/src/modules/builder/wall/Instances/instance/helpers/useWallClassification.ts
@@ -6,9 +6,19 @@ export function useWallClassification(walls: Walls) {
         if (walls.length < 3) return [];
 
         const wallSet = new Map<string, Wall>();
+        const positionPairSet = new Set<string>();
 
         const makeKey = (p1: Point, p2: Point) => {
-            return [p1.pointUuid, p2.pointUuid].sort().join("-");
+            return [p1.pointUuid, p2.pointUuid].sort((a, b) => a.localeCompare(b)).join("-");
+        };
+
+        const makePositionPairKey = (p1: Point, p2: Point) => {
+            const sortedPositions = [
+                [p1.position[0].toFixed(6), p1.position[2].toFixed(6)],
+                [p2.position[0].toFixed(6), p2.position[2].toFixed(6)],
+            ].sort((a, b) => a[0].localeCompare(b[0]) || a[1].localeCompare(b[1]));
+
+            return sortedPositions.map((pos) => pos.join(",")).join("|");
         };
 
         for (const wall of walls) {
@@ -18,6 +28,14 @@ export function useWallClassification(walls: Walls) {
                 continue;
             }
 
+            const positionPairKey = makePositionPairKey(p1, p2);
+
+            if (positionPairSet.has(positionPairKey)) {
+                continue;
+            }
+
+            positionPairSet.add(positionPairKey);
+
             const key = makeKey(p1, p2);
             if (!wallSet.has(key)) {
                 wallSet.set(key, wall);