diff --git a/js/id/core/relation.js b/js/id/core/relation.js
index f233ac470..049c4ddd9 100644
--- a/js/id/core/relation.js
+++ b/js/id/core/relation.js
@@ -134,24 +134,26 @@ _.extend(iD.Relation.prototype, {
     },
 
     asGeoJSON: function(resolver) {
-        if (this.isMultipolygon()) {
-            return {
-                type: 'Feature',
-                properties: this.tags,
-                geometry: {
-                    type: 'MultiPolygon',
-                    coordinates: this.multipolygon(resolver)
-                }
-            };
-        } else {
-            return {
-                type: 'FeatureCollection',
-                properties: this.tags,
-                features: this.members.map(function(member) {
-                    return _.extend({role: member.role}, resolver.entity(member.id).asGeoJSON(resolver));
-                })
-            };
-        }
+        return resolver.transient(this, 'GeoJSON', function () {
+            if (this.isMultipolygon()) {
+                return {
+                    type: 'Feature',
+                    properties: this.tags,
+                    geometry: {
+                        type: 'MultiPolygon',
+                        coordinates: this.multipolygon(resolver)
+                    }
+                };
+            } else {
+                return {
+                    type: 'FeatureCollection',
+                    properties: this.tags,
+                    features: this.members.map(function (member) {
+                        return _.extend({role: member.role}, resolver.entity(member.id).asGeoJSON(resolver));
+                    })
+                };
+            }
+        });
     },
 
     isMultipolygon: function() {
diff --git a/js/id/core/way.js b/js/id/core/way.js
index f62d58dd7..c0b5fb058 100644
--- a/js/id/core/way.js
+++ b/js/id/core/way.js
@@ -137,39 +137,41 @@ _.extend(iD.Way.prototype, {
     },
 
     asGeoJSON: function(resolver, polygon) {
-        var nodes = resolver.childNodes(this);
+        return resolver.transient(this, 'GeoJSON', function() {
+            var nodes = resolver.childNodes(this);
 
-        if (this.isArea() && polygon && nodes.length >= 4) {
-            if (!this.isClosed()) {
-                nodes = nodes.concat([nodes[0]]);
-            }
-
-            var json = {
-                type: 'Feature',
-                properties: this.tags,
-                geometry: {
-                    type: 'Polygon',
-                    coordinates: [_.pluck(nodes, 'loc')]
+            if (this.isArea() && polygon && nodes.length >= 4) {
+                if (!this.isClosed()) {
+                    nodes = nodes.concat([nodes[0]]);
                 }
-            };
 
-            // Heuristic for detecting counterclockwise winding order. Assumes
-            // that OpenStreetMap polygons are not hemisphere-spanning.
-            if (d3.geo.area(json) > 2 * Math.PI) {
-                json.geometry.coordinates[0] = json.geometry.coordinates[0].reverse();
-            }
+                var json = {
+                    type: 'Feature',
+                    properties: this.tags,
+                    geometry: {
+                        type: 'Polygon',
+                        coordinates: [_.pluck(nodes, 'loc')]
+                    }
+                };
 
-            return json;
-        } else {
-            return {
-                type: 'Feature',
-                properties: this.tags,
-                geometry: {
-                    type: 'LineString',
-                    coordinates: _.pluck(nodes, 'loc')
+                // Heuristic for detecting counterclockwise winding order. Assumes
+                // that OpenStreetMap polygons are not hemisphere-spanning.
+                if (d3.geo.area(json) > 2 * Math.PI) {
+                    json.geometry.coordinates[0] = json.geometry.coordinates[0].reverse();
                 }
-            };
-        }
+
+                return json;
+            } else {
+                return {
+                    type: 'Feature',
+                    properties: this.tags,
+                    geometry: {
+                        type: 'LineString',
+                        coordinates: _.pluck(nodes, 'loc')
+                    }
+                };
+            }
+        });
     }
 });