diff --git a/AsyncDisplayKit/Layout/ASDimension.mm b/AsyncDisplayKit/Layout/ASDimension.mm
index 53b03b7670..cf58e1c517 100644
--- a/AsyncDisplayKit/Layout/ASDimension.mm
+++ b/AsyncDisplayKit/Layout/ASDimension.mm
@@ -18,16 +18,21 @@ ASRelativeDimension const ASRelativeDimensionUnconstrained = {};
 ASRelativeDimension ASRelativeDimensionMake(ASRelativeDimensionType type, CGFloat value)
 {
   if (type == ASRelativeDimensionTypePoints) { ASDisplayNodeCAssertPositiveReal(@"Points", value); }
+  if (type == ASRelativeDimensionTypePercent) {
+    ASDisplayNodeCAssert( 0 <= value && value <= 1.0, @"ASRelativeDimension percent value (%f) must be between 0 and 1.", value);
+  }
   ASRelativeDimension dimension; dimension.type = type; dimension.value = value; return dimension;
 }
 
 ASRelativeDimension ASRelativeDimensionMakeWithPoints(CGFloat points)
 {
+  ASDisplayNodeCAssertPositiveReal(@"Points", points);
   return ASRelativeDimensionMake(ASRelativeDimensionTypePoints, points);
 }
 
 ASRelativeDimension ASRelativeDimensionMakeWithPercent(CGFloat percent)
 {
+  ASDisplayNodeCAssert( 0 <= percent && percent <= 1.0, @"ASRelativeDimension percent value (%f) must be between 0 and 1.", percent);
   return ASRelativeDimensionMake(ASRelativeDimensionTypePercent, percent);
 }