diff --git a/js/isotope.js b/js/isotope.js
index 7a3621e..86fa44e 100644
--- a/js/isotope.js
+++ b/js/isotope.js
@@ -80,7 +80,7 @@ var trim = String.prototype.trim ?
 
   // create an Outlayer layout class
   var Isotope = Outlayer.create( 'isotope', {
-    layoutMode: "masonry",
+    layoutMode: 'masonry',
     isJQueryFiltering: true,
     sortAscending: true
   });
@@ -88,7 +88,9 @@ var trim = String.prototype.trim ?
   Isotope.Item = Item;
   Isotope.LayoutMode = LayoutMode;
 
-  Isotope.prototype._create = function() {
+  var proto = Isotope.prototype;
+
+  proto._create = function() {
     this.itemGUID = 0;
     // functions that sort items
     this._sorters = {};
@@ -108,14 +110,14 @@ var trim = String.prototype.trim ?
     }
   };
 
-  Isotope.prototype.reloadItems = function() {
+  proto.reloadItems = function() {
     // reset item ID counter
     this.itemGUID = 0;
     // call super
     Outlayer.prototype.reloadItems.call( this );
   };
 
-  Isotope.prototype._itemize = function() {
+  proto._itemize = function() {
     var items = Outlayer.prototype._itemize.apply( this, arguments );
     // assign ID for original-order
     for ( var i=0; i < items.length; i++ ) {
@@ -129,7 +131,7 @@ var trim = String.prototype.trim ?
 
   // -------------------------- layout -------------------------- //
 
-  Isotope.prototype._initLayoutMode = function( name ) {
+  proto._initLayoutMode = function( name ) {
     var Mode = LayoutMode.modes[ name ];
     // set mode options
     // HACK extend initial options, back-fill in default options
@@ -141,7 +143,7 @@ var trim = String.prototype.trim ?
   };
 
 
-  Isotope.prototype.layout = function() {
+  proto.layout = function() {
     // if first time doing layout, do all magic
     if ( !this._isLayoutInited && this._getOption('initLayout') ) {
       this.arrange();
@@ -151,7 +153,7 @@ var trim = String.prototype.trim ?
   };
 
   // private method to be used in layout() & magic()
-  Isotope.prototype._layout = function() {
+  proto._layout = function() {
     // don't animate first layout
     var isInstant = this._getIsInstant();
     // layout flow
@@ -164,7 +166,7 @@ var trim = String.prototype.trim ?
   };
 
   // filter + sort + layout
-  Isotope.prototype.arrange = function( opts ) {
+  proto.arrange = function( opts ) {
     // set any options pass
     this.option( opts );
     this._getIsInstant();
@@ -186,9 +188,9 @@ var trim = String.prototype.trim ?
     this._layout();
   };
   // alias to _init for main plugin method
-  Isotope.prototype._init = Isotope.prototype.arrange;
+  proto._init = proto.arrange;
 
-  Isotope.prototype._hideReveal = function( filtered ) {
+  proto._hideReveal = function( filtered ) {
     this.reveal( filtered.needReveal );
     this.hide( filtered.needHide );
   };
@@ -196,7 +198,7 @@ var trim = String.prototype.trim ?
   // HACK
   // Don't animate/transition first layout
   // Or don't animate/transition other layouts
-  Isotope.prototype._getIsInstant = function() {
+  proto._getIsInstant = function() {
     var isLayoutInstant = this._getOption('layoutInstant');
     var isInstant = isLayoutInstant !== undefined ? isLayoutInstant :
       !this._isLayoutInited;
@@ -206,7 +208,7 @@ var trim = String.prototype.trim ?
 
   // listen for layoutComplete, hideComplete and revealComplete
   // to trigger arrangeComplete
-  Isotope.prototype._bindArrangeComplete = function() {
+  proto._bindArrangeComplete = function() {
     // listen for 3 events to trigger arrangeComplete
     var isLayoutComplete, isHideComplete, isRevealComplete;
     var _this = this;
@@ -231,7 +233,7 @@ var trim = String.prototype.trim ?
 
   // -------------------------- filter -------------------------- //
 
-  Isotope.prototype._filter = function( items ) {
+  proto._filter = function( items ) {
     var filter = this.options.filter;
     filter = filter || '*';
     var matches = [];
@@ -270,7 +272,7 @@ var trim = String.prototype.trim ?
   };
 
   // get a jQuery, function, or a matchesSelector test given the filter
-  Isotope.prototype._getFilterTest = function( filter ) {
+  proto._getFilterTest = function( filter ) {
     if ( jQuery && this.options.isJQueryFiltering ) {
       // use jQuery
       return function( item ) {
@@ -295,7 +297,7 @@ var trim = String.prototype.trim ?
    * @params {Array} elems
    * @public
    */
-  Isotope.prototype.updateSortData = function( elems ) {
+  proto.updateSortData = function( elems ) {
     // get items
     var items;
     if ( elems ) {
@@ -310,7 +312,7 @@ var trim = String.prototype.trim ?
     this._updateItemsSortData( items );
   };
 
-  Isotope.prototype._getSorters = function() {
+  proto._getSorters = function() {
     var getSortData = this.options.getSortData;
     for ( var key in getSortData ) {
       var sorter = getSortData[ key ];
@@ -322,7 +324,7 @@ var trim = String.prototype.trim ?
    * @params {Array} items - of Isotope.Items
    * @private
    */
-  Isotope.prototype._updateItemsSortData = function( items ) {
+  proto._updateItemsSortData = function( items ) {
     // do not update if no items
     var len = items && items.length;
 
@@ -400,7 +402,7 @@ var trim = String.prototype.trim ?
   // ----- sort method ----- //
 
   // sort filteredItem order
-  Isotope.prototype._sort = function() {
+  proto._sort = function() {
     var sortByOpt = this.options.sortBy;
     if ( !sortByOpt ) {
       return;
@@ -439,7 +441,7 @@ var trim = String.prototype.trim ?
   // -------------------------- methods -------------------------- //
 
   // get layout mode
-  Isotope.prototype._mode = function() {
+  proto._mode = function() {
     var layoutMode = this.options.layoutMode;
     var mode = this.modes[ layoutMode ];
     if ( !mode ) {
@@ -452,32 +454,32 @@ var trim = String.prototype.trim ?
     return mode;
   };
 
-  Isotope.prototype._resetLayout = function() {
+  proto._resetLayout = function() {
     // trigger original reset layout
     Outlayer.prototype._resetLayout.call( this );
     this._mode()._resetLayout();
   };
 
-  Isotope.prototype._getItemLayoutPosition = function( item  ) {
+  proto._getItemLayoutPosition = function( item  ) {
     return this._mode()._getItemLayoutPosition( item );
   };
 
-  Isotope.prototype._manageStamp = function( stamp ) {
+  proto._manageStamp = function( stamp ) {
     this._mode()._manageStamp( stamp );
   };
 
-  Isotope.prototype._getContainerSize = function() {
+  proto._getContainerSize = function() {
     return this._mode()._getContainerSize();
   };
 
-  Isotope.prototype.needsResizeLayout = function() {
+  proto.needsResizeLayout = function() {
     return this._mode().needsResizeLayout();
   };
 
   // -------------------------- adding & removing -------------------------- //
 
   // HEADS UP overwrites default Outlayer appended
-  Isotope.prototype.appended = function( elems ) {
+  proto.appended = function( elems ) {
     var items = this.addItems( elems );
     if ( !items.length ) {
       return;
@@ -489,7 +491,7 @@ var trim = String.prototype.trim ?
   };
 
   // HEADS UP overwrites default Outlayer prepended
-  Isotope.prototype.prepended = function( elems ) {
+  proto.prepended = function( elems ) {
     var items = this._itemize( elems );
     if ( !items.length ) {
       return;
@@ -506,7 +508,7 @@ var trim = String.prototype.trim ?
     this.items = items.concat( this.items );
   };
 
-  Isotope.prototype._filterRevealAdded = function( items ) {
+  proto._filterRevealAdded = function( items ) {
     var filtered = this._filter( items );
     this.hide( filtered.needHide );
     // reveal all new items
@@ -520,7 +522,7 @@ var trim = String.prototype.trim ?
    * Filter, sort, and layout newly-appended item elements
    * @param {Array or NodeList or Element} elems
    */
-  Isotope.prototype.insert = function( elems ) {
+  proto.insert = function( elems ) {
     var items = this.addItems( elems );
     if ( !items.length ) {
       return;
@@ -546,8 +548,8 @@ var trim = String.prototype.trim ?
     this.reveal( filteredInsertItems );
   };
 
-  var _remove = Isotope.prototype.remove;
-  Isotope.prototype.remove = function( elems ) {
+  var _remove = proto.remove;
+  proto.remove = function( elems ) {
     elems = utils.makeArray( elems );
     var removeItems = this.getItems( elems );
     // do regular thing
@@ -565,7 +567,7 @@ var trim = String.prototype.trim ?
     }
   };
 
-  Isotope.prototype.shuffle = function() {
+  proto.shuffle = function() {
     // update random sortData
     for ( var i=0; i < this.items.length; i++ ) {
       var item = this.items[i];
@@ -584,7 +586,7 @@ var trim = String.prototype.trim ?
    * @returns ret
    * @private
    */
-  Isotope.prototype._noTransition = function( fn, args ) {
+  proto._noTransition = function( fn, args ) {
     // save transitionDuration before disabling
     var transitionDuration = this.options.transitionDuration;
     // disable transition
@@ -602,7 +604,7 @@ var trim = String.prototype.trim ?
    * getter method for getting filtered item elements
    * @returns {Array} elems - collection of item elements
    */
-  Isotope.prototype.getFilteredItemElements = function() {
+  proto.getFilteredItemElements = function() {
     return this.filteredItems.map( function( item ) {
       return item.element;
     });
diff --git a/js/item.js b/js/item.js
index 40aa25c..d2549bc 100644
--- a/js/item.js
+++ b/js/item.js
@@ -34,16 +34,17 @@ function Item() {
   Outlayer.Item.apply( this, arguments );
 }
 
-Item.prototype = new Outlayer.Item();
+var proto = Item.prototype = Object.create( Outlayer.Item.prototype );
 
-Item.prototype._create = function() {
+var _create = proto._create;
+proto._create = function() {
   // assign id, used for original-order sorting
   this.id = this.layout.itemGUID++;
-  Outlayer.Item.prototype._create.call( this );
+  _create.call( this );
   this.sortData = {};
 };
 
-Item.prototype.updateSortData = function() {
+proto.updateSortData = function() {
   if ( this.isIgnored ) {
     return;
   }
@@ -61,8 +62,8 @@ Item.prototype.updateSortData = function() {
   }
 };
 
-var _destroy = Item.prototype.destroy;
-Item.prototype.destroy = function() {
+var _destroy = proto.destroy;
+proto.destroy = function() {
   // call super
   _destroy.apply( this, arguments );
   // reset display, #741
diff --git a/js/layout-mode.js b/js/layout-mode.js
index ffc3589..e569de4 100644
--- a/js/layout-mode.js
+++ b/js/layout-mode.js
@@ -43,6 +43,8 @@
     }
   }
 
+  var proto = LayoutMode.prototype;
+
   /**
    * some methods should just defer to default Outlayer method
    * and reference the Isotope instance as `this`
@@ -58,7 +60,7 @@
   ];
 
   facadeMethods.forEach( function( methodName ) {
-    LayoutMode.prototype[ methodName ] = function() {
+    proto[ methodName ] = function() {
       return Outlayer.prototype[ methodName ].apply( this.isotope, arguments );
     };
   });
@@ -66,7 +68,7 @@
   // -----  ----- //
 
   // for horizontal layout modes, check vertical size
-  LayoutMode.prototype.needsVerticalResizeLayout = function() {
+  proto.needsVerticalResizeLayout = function() {
     // don't trigger if size did not change
     var size = getSize( this.isotope.element );
     // check that this.size and size are there
@@ -77,15 +79,15 @@
 
   // ----- measurements ----- //
 
-  LayoutMode.prototype._getMeasurement = function() {
+  proto._getMeasurement = function() {
     this.isotope._getMeasurement.apply( this, arguments );
   };
 
-  LayoutMode.prototype.getColumnWidth = function() {
+  proto.getColumnWidth = function() {
     this.getSegmentSize( 'column', 'Width' );
   };
 
-  LayoutMode.prototype.getRowHeight = function() {
+  proto.getRowHeight = function() {
     this.getSegmentSize( 'row', 'Height' );
   };
 
@@ -94,7 +96,7 @@
    * segment: 'column' or 'row'
    * size 'Width' or 'Height'
   **/
-  LayoutMode.prototype.getSegmentSize = function( segment, size ) {
+  proto.getSegmentSize = function( segment, size ) {
     var segmentName = segment + size;
     var outerSize = 'outer' + size;
     // columnWidth / outerWidth // rowHeight / outerHeight
@@ -110,18 +112,18 @@
       this.isotope.size[ 'inner' + size ];
   };
 
-  LayoutMode.prototype.getFirstItemSize = function() {
+  proto.getFirstItemSize = function() {
     var firstItem = this.isotope.filteredItems[0];
     return firstItem && firstItem.element && getSize( firstItem.element );
   };
 
   // ----- methods that should reference isotope ----- //
 
-  LayoutMode.prototype.layout = function() {
+  proto.layout = function() {
     this.isotope.layout.apply( this.isotope, arguments );
   };
 
-  LayoutMode.prototype.getSize = function() {
+  proto.getSize = function() {
     this.isotope.getSize();
     this.size = this.isotope.size;
   };
@@ -136,7 +138,7 @@
       LayoutMode.apply( this, arguments );
     }
 
-    Mode.prototype = Object.create( LayoutMode.prototype );
+    Mode.prototype = Object.create( proto );
     Mode.prototype.constructor = Mode;
 
     // default options
diff --git a/js/layout-modes/fit-rows.js b/js/layout-modes/fit-rows.js
index 582d2c5..ef52c63 100644
--- a/js/layout-modes/fit-rows.js
+++ b/js/layout-modes/fit-rows.js
@@ -28,14 +28,16 @@
 
 var FitRows = LayoutMode.create('fitRows');
 
-FitRows.prototype._resetLayout = function() {
+var proto = FitRows.prototype;
+
+proto._resetLayout = function() {
   this.x = 0;
   this.y = 0;
   this.maxY = 0;
   this._getMeasurement( 'gutter', 'outerWidth' );
 };
 
-FitRows.prototype._getItemLayoutPosition = function( item ) {
+proto._getItemLayoutPosition = function( item ) {
   item.getSize();
 
   var itemWidth = item.size.outerWidth + this.gutter;
@@ -57,7 +59,7 @@ FitRows.prototype._getItemLayoutPosition = function( item ) {
   return position;
 };
 
-FitRows.prototype._getContainerSize = function() {
+proto._getContainerSize = function() {
   return { height: this.maxY };
 };
 
diff --git a/js/layout-modes/vertical.js b/js/layout-modes/vertical.js
index 35c425e..2d05a7a 100644
--- a/js/layout-modes/vertical.js
+++ b/js/layout-modes/vertical.js
@@ -30,11 +30,13 @@ var Vertical = LayoutMode.create( 'vertical', {
   horizontalAlignment: 0
 });
 
-Vertical.prototype._resetLayout = function() {
+var proto = Vertical.prototype;
+
+proto._resetLayout = function() {
   this.y = 0;
 };
 
-Vertical.prototype._getItemLayoutPosition = function( item ) {
+proto._getItemLayoutPosition = function( item ) {
   item.getSize();
   var x = ( this.isotope.size.innerWidth - item.size.outerWidth ) *
     this.options.horizontalAlignment;
@@ -43,7 +45,7 @@ Vertical.prototype._getItemLayoutPosition = function( item ) {
   return { x: x, y: y };
 };
 
-Vertical.prototype._getContainerSize = function() {
+proto._getContainerSize = function() {
   return { height: this.y };
 };