diff --git a/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.m b/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.m
index e90cd461d6..5ce3b9bfb6 100644
--- a/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.m
+++ b/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.m
@@ -39,8 +39,8 @@
 - (void)didChangeCollectionViewDelegate:(id<ASCollectionViewDelegate>)delegate;
 {
   if (delegate == nil) {
-    _delegateImplementsReferenceSizeForHeader = nil;
-    _delegateImplementsReferenceSizeForFooter = nil;
+    _delegateImplementsReferenceSizeForHeader = NO;
+    _delegateImplementsReferenceSizeForFooter = NO;
   } else {
     _delegateImplementsReferenceSizeForHeader = [delegate respondsToSelector:@selector(collectionView:layout:referenceSizeForHeaderInSection:)];
     _delegateImplementsReferenceSizeForFooter = [delegate respondsToSelector:@selector(collectionView:layout:referenceSizeForFooterInSection:)];