diff --git a/resources/views/rd/fire-shutter-drawing/index.blade.php b/resources/views/rd/fire-shutter-drawing/index.blade.php
index 5ca8ea86..a81791b8 100644
--- a/resources/views/rd/fire-shutter-drawing/index.blade.php
+++ b/resources/views/rd/fire-shutter-drawing/index.blade.php
@@ -1280,28 +1280,45 @@ function fs3dBuild() {
         meshes.bottomBar.position.set(0, H - shutterH - 20, 0);
         scene.add(meshes.bottomBar);
 
-        // === WALL (3면 벽체: 좌날개 + 우날개 + 뒷벽) ===
+        // === WALL (개구부 뚫린 벽체: 좌벽 + 우벽 + 상부 인방 + 좌/우 날개벽) ===
         const wl = S.wall;
         const wallH = H + b.height + wl.topMargin; // 전체 벽 높이
         const wallColor = new THREE.Color(wl.color);
         const wallMat = new THREE.MeshStandardMaterial({ color: wallColor, transparent: true, opacity: wl.opacity / 100, side: THREE.DoubleSide });
         meshes.wall = new THREE.Group();
 
-        // 뒷벽 (전체 폭 커버: 날개벽 포함)
-        const totalW = W1 + wl.wing * 2;
-        const backGeo = new THREE.BoxGeometry(totalW, wallH, wl.thick);
-        const backMesh = new THREE.Mesh(backGeo, wallMat);
-        backMesh.position.set(0, wallH / 2, -wl.thick / 2);
-        meshes.wall.add(backMesh);
+        // 뒷벽: 개구부(W1 x H) 부분을 제외하고 3조각으로 구성
+        // 1) 좌측 뒷벽 (날개벽 폭만큼)
+        if (wl.wing > 0) {
+            const backLGeo = new THREE.BoxGeometry(wl.wing, wallH, wl.thick);
+            const backL = new THREE.Mesh(backLGeo, wallMat);
+            backL.position.set(-W1 / 2 - wl.wing / 2, wallH / 2, -wl.thick / 2);
+            meshes.wall.add(backL);
 
-        // 좌측 날개벽
+            // 2) 우측 뒷벽
+            const backR = new THREE.Mesh(backLGeo.clone(), wallMat);
+            backR.position.set(W1 / 2 + wl.wing / 2, wallH / 2, -wl.thick / 2);
+            meshes.wall.add(backR);
+        }
+
+        // 3) 상부 인방 (개구부 위, 셔터박스+상단여유 높이)
+        const lintelH = b.height + wl.topMargin;
+        if (lintelH > 0) {
+            const totalW = W1 + wl.wing * 2;
+            const lintelGeo = new THREE.BoxGeometry(totalW, lintelH, wl.thick);
+            const lintel = new THREE.Mesh(lintelGeo, wallMat);
+            lintel.position.set(0, H + lintelH / 2, -wl.thick / 2);
+            meshes.wall.add(lintel);
+        }
+
+        // 좌/우 날개벽 (앞쪽으로 돌출, 가이드레일 옆)
         if (wl.wing > 0) {
             const wingGeo = new THREE.BoxGeometry(wl.wing, wallH, wl.thick);
             const leftWing = new THREE.Mesh(wingGeo, wallMat);
             leftWing.position.set(-W1 / 2 - wl.wing / 2, wallH / 2, wl.thick / 2);
             meshes.wall.add(leftWing);
 
-            const rightWing = new THREE.Mesh(wingGeo, wallMat);
+            const rightWing = new THREE.Mesh(wingGeo.clone(), wallMat);
             rightWing.position.set(W1 / 2 + wl.wing / 2, wallH / 2, wl.thick / 2);
             meshes.wall.add(rightWing);
         }