diff --git a/src/geo/polygon.js b/src/geo/polygon.js
index fe4efe03..9de197e6 100644
--- a/src/geo/polygon.js
+++ b/src/geo/polygon.js
@@ -645,6 +645,13 @@
         }
     };
 
+    /**
+     * @returns {boolean} true if both polygons wind the same way
+     */
+    PRO.sameWindings = function(poly) {
+        return this.isClockwise() === poly.isClockwise();
+    };
+
     /**
      * reverse direction of polygon points.
      * @returns {Polygon} self
diff --git a/src/kiri/print.js b/src/kiri/print.js
index 27ea1e84..88cab303 100644
--- a/src/kiri/print.js
+++ b/src/kiri/print.js
@@ -1056,6 +1056,10 @@
                         // console.log({skip_open_above:above});
                         continue;
                     }
+                    // do not allow inner and outer polys to mix
+                    if (!above.sameWindings(pool)) {
+                        continue;
+                    }
                     // if pool fits into smallest above pool, add it and break
                     if (polygonFitsIn(pool, above, 0.1)) {
                         above.poolsDown.push(pool);