diff --git a/vulkano/src/framebuffer/traits.rs b/vulkano/src/framebuffer/traits.rs
index 80d4cf2f..670147c2 100644
--- a/vulkano/src/framebuffer/traits.rs
+++ b/vulkano/src/framebuffer/traits.rs
@@ -308,7 +308,39 @@ pub unsafe trait RenderPassDesc {
     }
 }
 
-unsafe impl<T> RenderPassDesc for Arc<T> where T: RenderPassDesc {
+unsafe impl<T: ?Sized> RenderPassDesc for Box<T> where T: RenderPassDesc {
+    #[inline]
+    fn num_attachments(&self) -> usize {
+        (**self).num_attachments()
+    }
+
+    #[inline]
+    fn attachment(&self, num: usize) -> Option<LayoutAttachmentDescription> {
+        (**self).attachment(num)
+    }
+
+    #[inline]
+    fn num_subpasses(&self) -> usize {
+        (**self).num_subpasses()
+    }
+
+    #[inline]
+    fn subpass(&self, num: usize) -> Option<LayoutPassDescription> {
+        (**self).subpass(num)
+    }
+
+    #[inline]
+    fn num_dependencies(&self) -> usize {
+        (**self).num_dependencies()
+    }
+
+    #[inline]
+    fn dependency(&self, num: usize) -> Option<LayoutPassDependencyDescription> {
+        (**self).dependency(num)
+    }
+}
+
+unsafe impl<T: ?Sized> RenderPassDesc for Arc<T> where T: RenderPassDesc {
     #[inline]
     fn num_attachments(&self) -> usize {
         (**self).num_attachments()