diff --git a/packages/core/src/store/actions/node-actions.ts b/packages/core/src/store/actions/node-actions.ts
index f4503c25..f6e64a7d 100644
--- a/packages/core/src/store/actions/node-actions.ts
+++ b/packages/core/src/store/actions/node-actions.ts
@@ -173,7 +173,14 @@ function buildWallMergePlans(
         continue
       }
 
-      const [primary, secondary] = candidates
+      const sortedCandidates = [...candidates].sort((a, b) => {
+        const attachmentDiff = (b.children?.length ?? 0) - (a.children?.length ?? 0)
+        if (attachmentDiff !== 0) {
+          return attachmentDiff
+        }
+        return a.id.localeCompare(b.id)
+      })
+      const [primary, secondary] = sortedCandidates
       if (
         !primary ||
         !secondary ||
diff --git a/packages/viewer/src/components/renderers/door/door-renderer.tsx b/packages/viewer/src/components/renderers/door/door-renderer.tsx
index 9d87eba1..6c978f3e 100644
--- a/packages/viewer/src/components/renderers/door/door-renderer.tsx
+++ b/packages/viewer/src/components/renderers/door/door-renderer.tsx
@@ -1,5 +1,5 @@
-import { type DoorNode, useRegistry } from '@pascal-app/core'
-import { useMemo, useRef } from 'react'
+import { type DoorNode, useRegistry, useScene } from '@pascal-app/core'
+import { useLayoutEffect, useMemo, useRef } from 'react'
 import type { Mesh } from 'three'
 import { useNodeEvents } from '../../../hooks/use-node-events'
 import { createMaterial, DEFAULT_DOOR_MATERIAL } from '../../../lib/materials'
@@ -8,6 +8,9 @@ export const DoorRenderer = ({ node }: { node: DoorNode }) => {
   const ref = useRef<Mesh>(null!)
 
   useRegistry(node.id, 'door', ref)
+  useLayoutEffect(() => {
+    useScene.getState().markDirty(node.id)
+  }, [node.id])
   const handlers = useNodeEvents(node, 'door')
   const isTransient = !!(node.metadata as Record<string, unknown> | null)?.isTransient
 
diff --git a/packages/viewer/src/components/renderers/wall/wall-renderer.tsx b/packages/viewer/src/components/renderers/wall/wall-renderer.tsx
index f4e3fab9..ef6f70cf 100644
--- a/packages/viewer/src/components/renderers/wall/wall-renderer.tsx
+++ b/packages/viewer/src/components/renderers/wall/wall-renderer.tsx
@@ -42,7 +42,7 @@ export const WallRenderer = ({ node }: { node: WallNode }) => {
       </mesh>
 
       {node.children.map((childId) => (
-        <NodeRenderer key={childId} nodeId={childId} />
+        <NodeRenderer key={`${node.id}:${childId}`} nodeId={childId} />
       ))}
     </mesh>
   )
diff --git a/packages/viewer/src/components/renderers/window/window-renderer.tsx b/packages/viewer/src/components/renderers/window/window-renderer.tsx
index 1f5c2c8e..c953812f 100644
--- a/packages/viewer/src/components/renderers/window/window-renderer.tsx
+++ b/packages/viewer/src/components/renderers/window/window-renderer.tsx
@@ -1,5 +1,5 @@
-import { useRegistry, type WindowNode } from '@pascal-app/core'
-import { useMemo, useRef } from 'react'
+import { useRegistry, useScene, type WindowNode } from '@pascal-app/core'
+import { useLayoutEffect, useMemo, useRef } from 'react'
 import type { Mesh } from 'three'
 import { useNodeEvents } from '../../../hooks/use-node-events'
 import { createMaterial, DEFAULT_WINDOW_MATERIAL } from '../../../lib/materials'
@@ -8,6 +8,9 @@ export const WindowRenderer = ({ node }: { node: WindowNode }) => {
   const ref = useRef<Mesh>(null!)
 
   useRegistry(node.id, 'window', ref)
+  useLayoutEffect(() => {
+    useScene.getState().markDirty(node.id)
+  }, [node.id])
   const handlers = useNodeEvents(node, 'window')
   const isTransient = !!(node.metadata as Record<string, unknown> | null)?.isTransient