diff --git a/src/ol/style/fillsymbolizer.js b/src/ol/style/fillsymbolizer.js
index 6305315c12..0ef25c967a 100644
--- a/src/ol/style/fillsymbolizer.js
+++ b/src/ol/style/fillsymbolizer.js
@@ -43,7 +43,7 @@ ol.style.Fill = function(opt_options) {
    * @private
    */
   this.zIndex_ = !goog.isDefAndNotNull(options.zIndex) ?
-      null :
+      new ol.expr.Literal(ol.style.FillDefaults.zIndex) :
       (options.zIndex instanceof ol.expr.Expression) ?
           options.zIndex : new ol.expr.Literal(options.zIndex);
 
@@ -76,11 +76,8 @@ ol.style.Fill.prototype.createLiteral = function(featureOrType) {
     var opacity = Number(ol.expr.evaluateFeature(this.opacity_, feature));
     goog.asserts.assert(!isNaN(opacity), 'opacity must be a number');
 
-    var zIndex;
-    if (!goog.isNull(this.zIndex_)) {
-      zIndex = Number(ol.expr.evaluateFeature(this.zIndex_, feature));
-      goog.asserts.assert(!isNaN(zIndex), 'zIndex must be a number');
-    }
+    var zIndex = Number(ol.expr.evaluateFeature(this.zIndex_, feature));
+    goog.asserts.assert(!isNaN(zIndex), 'zIndex must be a number');
 
     literal = new ol.style.PolygonLiteral({
       fillColor: color,
@@ -151,10 +148,12 @@ ol.style.Fill.prototype.setZIndex = function(zIndex) {
 
 
 /**
- * @typedef {{fillColor: (string),
- *            fillOpacity: (number)}}
+ * @typedef {{fillColor: string,
+ *            fillOpacity: number,
+ *            zIndex: number}}
  */
 ol.style.FillDefaults = {
   color: '#ffffff',
-  opacity: 0.4
+  opacity: 0.4,
+  zIndex: 0
 };
diff --git a/src/ol/style/iconliteral.js b/src/ol/style/iconliteral.js
index c84997e0af..81ee54f326 100644
--- a/src/ol/style/iconliteral.js
+++ b/src/ol/style/iconliteral.js
@@ -1,5 +1,6 @@
 goog.provide('ol.style.IconLiteral');
 
+goog.require('goog.asserts');
 goog.require('ol.style.PointLiteral');
 
 
@@ -11,7 +12,7 @@ goog.require('ol.style.PointLiteral');
  *            rotation: number,
  *            xOffset: number,
  *            yOffset: number,
- *            zIndex: (number|undefined)}}
+ *            zIndex: number}}
  */
 ol.style.IconLiteralOptions;
 
@@ -45,7 +46,9 @@ ol.style.IconLiteral = function(options) {
   /** @type {number} */
   this.yOffset = options.yOffset;
 
-  /** @type {number|undefined} */
+  goog.asserts.assertNumber(
+      options.zIndex, 'zIndex must be a number');
+  /** @type {number} */
   this.zIndex = options.zIndex;
 
 };
diff --git a/src/ol/style/iconsymbolizer.js b/src/ol/style/iconsymbolizer.js
index 78f6e3eb89..284dce51fe 100644
--- a/src/ol/style/iconsymbolizer.js
+++ b/src/ol/style/iconsymbolizer.js
@@ -86,7 +86,7 @@ ol.style.Icon = function(options) {
    * @private
    */
   this.zIndex_ = !goog.isDefAndNotNull(options.zIndex) ?
-      null :
+      new ol.expr.Literal(ol.style.IconDefaults.zIndex) :
       (options.zIndex instanceof ol.expr.Expression) ?
           options.zIndex : new ol.expr.Literal(options.zIndex);
 
@@ -139,11 +139,8 @@ ol.style.Icon.prototype.createLiteral = function(featureOrType) {
     var yOffset = Number(ol.expr.evaluateFeature(this.yOffset_, feature));
     goog.asserts.assert(!isNaN(yOffset), 'yOffset must be a number');
 
-    var zIndex;
-    if (!goog.isNull(this.zIndex_)) {
-      zIndex = Number(ol.expr.evaluateFeature(this.zIndex_, feature));
-      goog.asserts.assert(!isNaN(zIndex), 'zIndex must be a number');
-    }
+    var zIndex = Number(ol.expr.evaluateFeature(this.zIndex_, feature));
+    goog.asserts.assert(!isNaN(zIndex), 'zIndex must be a number');
 
     literal = new ol.style.IconLiteral({
       url: url,
@@ -317,11 +314,13 @@ ol.style.Icon.prototype.setZIndex = function(zIndex) {
  * @typedef {{opacity: number,
  *            rotation: number,
  *            xOffset: number,
- *            yOffset: number}}
+ *            yOffset: number,
+ *            zIndex: number}}
  */
 ol.style.IconDefaults = {
   opacity: 1,
   rotation: 0,
   xOffset: 0,
-  yOffset: 0
+  yOffset: 0,
+  zIndex: 0
 };
diff --git a/src/ol/style/lineliteral.js b/src/ol/style/lineliteral.js
index 6ba2759d8e..c13198c630 100644
--- a/src/ol/style/lineliteral.js
+++ b/src/ol/style/lineliteral.js
@@ -5,10 +5,10 @@ goog.require('ol.style.Literal');
 
 
 /**
- * @typedef {{color: (string),
- *            opacity: (number),
- *            width: (number),
- *            zIndex: (number|undefined)}}
+ * @typedef {{color: string,
+ *            opacity: number,
+ *            width: number,
+ *            zIndex: number}}
  */
 ol.style.LineLiteralOptions;
 
@@ -37,7 +37,9 @@ ol.style.LineLiteral = function(options) {
   /** @type {number} */
   this.width = options.width;
 
-  /** @type {number|undefined} */
+  goog.asserts.assertNumber(
+      options.zIndex, 'zIndex must be a number');
+  /** @type {number} */
   this.zIndex = options.zIndex;
 
 };
diff --git a/src/ol/style/polygonliteral.js b/src/ol/style/polygonliteral.js
index 3b6c4316f3..e16c482860 100644
--- a/src/ol/style/polygonliteral.js
+++ b/src/ol/style/polygonliteral.js
@@ -10,7 +10,7 @@ goog.require('ol.style.Literal');
  *            strokeColor: (string|undefined),
  *            strokeOpacity: (number|undefined),
  *            strokeWidth: (number|undefined),
- *            zIndex: (number|undefined)}}
+ *            zIndex: number}}
  */
 ol.style.PolygonLiteralOptions;
 
@@ -67,7 +67,9 @@ ol.style.PolygonLiteral = function(options) {
       'Either fillColor and fillOpacity or ' +
       'strokeColor and strokeOpacity and strokeWidth must be set');
 
-  /** @type {number|undefined} */
+  goog.asserts.assertNumber(
+      options.zIndex, 'zIndex must be a number');
+  /** @type {number} */
   this.zIndex = options.zIndex;
 
 };
diff --git a/src/ol/style/shapeliteral.js b/src/ol/style/shapeliteral.js
index 9d95a2418f..602c58c28b 100644
--- a/src/ol/style/shapeliteral.js
+++ b/src/ol/style/shapeliteral.js
@@ -21,7 +21,7 @@ ol.style.ShapeType = {
  *            strokeColor: (string|undefined),
  *            strokeOpacity: (number|undefined),
  *            strokeWidth: (number|undefined),
- *            zIndex: (number|undefined)}}
+ *            zIndex: number}}
  */
 ol.style.ShapeLiteralOptions;
 
@@ -85,7 +85,9 @@ ol.style.ShapeLiteral = function(options) {
       'Either fillColor and fillOpacity or ' +
       'strokeColor and strokeOpacity and strokeWidth must be set');
 
-  /** @type {number|undefined} */
+  goog.asserts.assertNumber(
+      options.zIndex, 'zIndex must be a number');
+  /** @type {number} */
   this.zIndex = options.zIndex;
 
 };
diff --git a/src/ol/style/shapesymbolizer.js b/src/ol/style/shapesymbolizer.js
index d9074319f1..6c4ffde4f8 100644
--- a/src/ol/style/shapesymbolizer.js
+++ b/src/ol/style/shapesymbolizer.js
@@ -58,7 +58,7 @@ ol.style.Shape = function(options) {
    * @private
    */
   this.zIndex_ = !goog.isDefAndNotNull(options.zIndex) ?
-      null :
+      new ol.expr.Literal(ol.style.ShapeDefaults.zIndex) :
       (options.zIndex instanceof ol.expr.Expression) ?
           options.zIndex : new ol.expr.Literal(options.zIndex);
 
@@ -109,11 +109,8 @@ ol.style.Shape.prototype.createLiteral = function(featureOrType) {
       goog.asserts.assert(!isNaN(strokeWidth), 'strokeWidth must be a number');
     }
 
-    var zIndex;
-    if (!goog.isNull(this.zIndex_)) {
-      zIndex = Number(ol.expr.evaluateFeature(this.zIndex_, feature));
-      goog.asserts.assert(!isNaN(zIndex), 'zIndex must be a number');
-    }
+    var zIndex = Number(ol.expr.evaluateFeature(this.zIndex_, feature));
+    goog.asserts.assert(!isNaN(zIndex), 'zIndex must be a number');
 
     literal = new ol.style.ShapeLiteral({
       type: this.type_,
@@ -230,10 +227,12 @@ ol.style.Shape.prototype.setZIndex = function(zIndex) {
 
 
 /**
- * @typedef {{type: (ol.style.ShapeType),
- *            size: (number)}}
+ * @typedef {{type: ol.style.ShapeType,
+ *            size: number,
+ *            zIndex: number}}
  */
 ol.style.ShapeDefaults = {
   type: ol.style.ShapeType.CIRCLE,
-  size: 5
+  size: 5,
+  zIndex: 0
 };
diff --git a/src/ol/style/strokesymbolizer.js b/src/ol/style/strokesymbolizer.js
index 6997f63e94..610c79fc4e 100644
--- a/src/ol/style/strokesymbolizer.js
+++ b/src/ol/style/strokesymbolizer.js
@@ -54,7 +54,7 @@ ol.style.Stroke = function(opt_options) {
    * @private
    */
   this.zIndex_ = !goog.isDefAndNotNull(options.zIndex) ?
-      null :
+      new ol.expr.Literal(ol.style.StrokeDefaults.zIndex) :
       (options.zIndex instanceof ol.expr.Expression) ?
           options.zIndex : new ol.expr.Literal(options.zIndex);
 
@@ -88,11 +88,8 @@ ol.style.Stroke.prototype.createLiteral = function(featureOrType) {
       this.width_, feature));
   goog.asserts.assert(!isNaN(width), 'width must be a number');
 
-  var zIndex;
-  if (!goog.isNull(this.zIndex_)) {
-    zIndex = Number(ol.expr.evaluateFeature(this.zIndex_, feature));
-    goog.asserts.assert(!isNaN(zIndex), 'zIndex must be a number');
-  }
+  var zIndex = Number(ol.expr.evaluateFeature(this.zIndex_, feature));
+  goog.asserts.assert(!isNaN(zIndex), 'zIndex must be a number');
 
   var literal = null;
   if (type === ol.geom.GeometryType.LINESTRING ||
@@ -194,24 +191,28 @@ ol.style.Stroke.prototype.setZIndex = function(zIndex) {
 
 
 /**
- * @typedef {{strokeColor: (string),
- *            strokeOpacity: (number),
- *            strokeWidth: (number)}}
+ * @typedef {{strokeColor: string,
+ *            strokeOpacity: number,
+ *            strokeWidth: number,
+ *            zIndex: number}}
  */
 ol.style.StrokeDefaults = {
   color: '#696969',
   opacity: 0.75,
-  width: 1.5
+  width: 1.5,
+  zIndex: 0
 };
 
 
 /**
- * @typedef {{color: (string),
- *            opacity: (number),
- *            width: (number)}}
+ * @typedef {{color: string,
+ *            opacity: number,
+ *            width: number,
+ *            zIndex: number}}
  */
 ol.style.StrokeDefaultsSelect = {
   color: '#696969',
   opacity: 0.9,
-  width: 2.0
+  width: 2.0,
+  zIndex: 0
 };
diff --git a/src/ol/style/textliteral.js b/src/ol/style/textliteral.js
index 948ccdf673..ec3036bed3 100644
--- a/src/ol/style/textliteral.js
+++ b/src/ol/style/textliteral.js
@@ -10,7 +10,7 @@ goog.require('ol.style.Literal');
  *            fontSize: number,
  *            text: string,
  *            opacity: number,
- *            zIndex: (number|undefined)}}
+ *            zIndex: number}}
  */
 ol.style.TextLiteralOptions;
 
@@ -43,7 +43,8 @@ ol.style.TextLiteral = function(options) {
   /** @type {number} */
   this.opacity = options.opacity;
 
-  /** @type {number|undefined} */
+  goog.asserts.assertNumber(options.zIndex, 'zIndex must be a number');
+  /** @type {number} */
   this.zIndex = options.zIndex;
 
 };
diff --git a/src/ol/style/textsymbolizer.js b/src/ol/style/textsymbolizer.js
index 3daac82b91..95e00864f0 100644
--- a/src/ol/style/textsymbolizer.js
+++ b/src/ol/style/textsymbolizer.js
@@ -65,7 +65,7 @@ ol.style.Text = function(options) {
    * @private
    */
   this.zIndex_ = !goog.isDefAndNotNull(options.zIndex) ?
-      null :
+      new ol.expr.Literal(ol.style.TextDefaults.zIndex) :
       (options.zIndex instanceof ol.expr.Expression) ?
           options.zIndex : new ol.expr.Literal(options.zIndex);
 
@@ -102,11 +102,8 @@ ol.style.Text.prototype.createLiteral = function(featureOrType) {
   var opacity = Number(ol.expr.evaluateFeature(this.opacity_, feature));
   goog.asserts.assert(!isNaN(opacity), 'opacity must be a number');
 
-  var zIndex;
-  if (!goog.isNull(this.zIndex_)) {
-    zIndex = Number(ol.expr.evaluateFeature(this.zIndex_, feature));
-    goog.asserts.assert(!isNaN(zIndex), 'zIndex must be a number');
-  }
+  var zIndex = Number(ol.expr.evaluateFeature(this.zIndex_, feature));
+  goog.asserts.assert(!isNaN(zIndex), 'zIndex must be a number');
 
   return new ol.style.TextLiteral({
     color: color,
@@ -237,11 +234,13 @@ ol.style.Text.prototype.setZIndex = function(zIndex) {
  * @typedef {{color: string,
  *            fontFamily: string,
  *            fontSize: number,
- *            opacity: number}}
+ *            opacity: number,
+ *            zIndex: number}}
  */
 ol.style.TextDefaults = {
   color: '#000',
   fontFamily: 'sans-serif',
   fontSize: 10,
-  opacity: 1
+  opacity: 1,
+  zIndex: 0
 };
diff --git a/test/spec/ol/style/fillsymbolizer.test.js b/test/spec/ol/style/fillsymbolizer.test.js
index 2d74b71730..d3b58223c7 100644
--- a/test/spec/ol/style/fillsymbolizer.test.js
+++ b/test/spec/ol/style/fillsymbolizer.test.js
@@ -49,7 +49,7 @@ describe('ol.style.Fill', function() {
       expect(literal).to.be.a(ol.style.PolygonLiteral);
       expect(literal.fillOpacity).to.be(42 / 100);
       expect(literal.fillColor).to.be('#ff0000');
-      expect(literal.zIndex).to.be(undefined);
+      expect(literal.zIndex).to.be(0);
     });
 
     it('applies default opacity', function() {
@@ -104,6 +104,33 @@ describe('ol.style.Fill', function() {
       expect(literal.zIndex).to.be(2);
     });
 
+    it('applies default zIndex', function() {
+      var symbolizer = new ol.style.Fill({
+        opacity: 0.8
+      });
+
+      var literal = symbolizer.createLiteral(ol.geom.GeometryType.POLYGON);
+      expect(literal).to.be.a(ol.style.PolygonLiteral);
+      expect(literal.zIndex).to.be(0);
+    });
+
+    it('casts zIndex to number', function() {
+      var symbolizer = new ol.style.Fill({
+        zIndex: ol.expr.parse('zIndex'),
+        color: '#ff00ff'
+      });
+
+      var feature = new ol.Feature({
+        zIndex: '11',
+        geometry: new ol.geom.Polygon(
+            [[[0, 0], [1, 0], [1, 1], [0, 1], [0, 0]]])
+      });
+
+      var literal = symbolizer.createLiteral(feature);
+      expect(literal).to.be.a(ol.style.PolygonLiteral);
+      expect(literal.zIndex).to.be(11);
+    });
+
   });
 
   describe('#getColor()', function() {
@@ -135,6 +162,21 @@ describe('ol.style.Fill', function() {
 
   });
 
+  describe('#getZIndex()', function() {
+
+    it('returns the zIndex', function() {
+      var symbolizer = new ol.style.Fill({
+        color: '#ffffff',
+        zIndex: 11
+      });
+
+      var zIndex = symbolizer.getZIndex();
+      expect(zIndex).to.be.a(ol.expr.Literal);
+      expect(zIndex.getValue()).to.be(11);
+    });
+
+  });
+
   describe('#setColor()', function() {
 
     it('sets the fill color', function() {
diff --git a/test/spec/ol/style/iconliteral.test.js b/test/spec/ol/style/iconliteral.test.js
index eac009d4e2..4f5aed80f1 100644
--- a/test/spec/ol/style/iconliteral.test.js
+++ b/test/spec/ol/style/iconliteral.test.js
@@ -10,49 +10,56 @@ describe('ol.style.IconLiteral', function() {
         width: 20,
         opacity: 1,
         rotation: 0.1,
-        url: 'http://example.com/1.png'
+        url: 'http://example.com/1.png',
+        zIndex: 0
       });
       var equalLiteral = new ol.style.IconLiteral({
         height: 10,
         width: 20,
         opacity: 1,
         rotation: 0.1,
-        url: 'http://example.com/1.png'
+        url: 'http://example.com/1.png',
+        zIndex: 0
       });
-      var differentLiteral1 = new ol.style.IconLiteral({
+      var differentHeight = new ol.style.IconLiteral({
         height: 11,
         width: 20,
         opacity: 1,
         rotation: 0.1,
-        url: 'http://example.com/1.png'
+        url: 'http://example.com/1.png',
+        zIndex: 0
       });
-      var differentLiteral2 = new ol.style.IconLiteral({
+      var differentWidth = new ol.style.IconLiteral({
         height: 10,
         width: 2,
         opacity: 1,
         rotation: 0.1,
-        url: 'http://example.com/1.png'
+        url: 'http://example.com/1.png',
+        zIndex: 0
       });
-      var differentLiteral3 = new ol.style.IconLiteral({
+      var differentOpacity = new ol.style.IconLiteral({
         height: 10,
         width: 20,
         opacity: 0.5,
         rotation: 0.1,
-        url: 'http://example.com/1.png'
+        url: 'http://example.com/1.png',
+        zIndex: 0
       });
-      var differentLiteral4 = new ol.style.IconLiteral({
+      var differentRotation = new ol.style.IconLiteral({
         height: 10,
         width: 20,
         opacity: 1,
         rotation: 0.2,
-        url: 'http://example.com/1.png'
+        url: 'http://example.com/1.png',
+        zIndex: 0
       });
-      var differentLiteral5 = new ol.style.IconLiteral({
+      var differentUrl = new ol.style.IconLiteral({
         height: 10,
         width: 20,
         opacity: 1,
         rotation: 0.1,
-        url: 'http://example.com/2.png'
+        url: 'http://example.com/2.png',
+        zIndex: 0
       });
       var differentZIndex = new ol.style.IconLiteral({
         height: 10,
@@ -63,11 +70,11 @@ describe('ol.style.IconLiteral', function() {
         zIndex: 20
       });
       expect(literal.equals(equalLiteral)).to.be(true);
-      expect(literal.equals(differentLiteral1)).to.be(false);
-      expect(literal.equals(differentLiteral2)).to.be(false);
-      expect(literal.equals(differentLiteral3)).to.be(false);
-      expect(literal.equals(differentLiteral4)).to.be(false);
-      expect(literal.equals(differentLiteral5)).to.be(false);
+      expect(literal.equals(differentHeight)).to.be(false);
+      expect(literal.equals(differentWidth)).to.be(false);
+      expect(literal.equals(differentOpacity)).to.be(false);
+      expect(literal.equals(differentRotation)).to.be(false);
+      expect(literal.equals(differentUrl)).to.be(false);
       expect(literal.equals(differentZIndex)).to.be(false);
     });
 
diff --git a/test/spec/ol/style/iconsymbolizer.test.js b/test/spec/ol/style/iconsymbolizer.test.js
index a0d712b79b..0f0a736f7d 100644
--- a/test/spec/ol/style/iconsymbolizer.test.js
+++ b/test/spec/ol/style/iconsymbolizer.test.js
@@ -77,7 +77,7 @@ describe('ol.style.Icon', function() {
       expect(literal.xOffset).to.be(20);
       expect(literal.yOffset).to.be(30);
       expect(literal.url).to.be('http://example.com/1.png');
-      expect(literal.zIndex).to.be(undefined);
+      expect(literal.zIndex).to.be(0);
     });
 
     it('can be called without a feature', function() {
@@ -250,6 +250,35 @@ describe('ol.style.Icon', function() {
       expect(literal.zIndex).to.be(4);
     });
 
+    it('applies default zIndex if none', function() {
+      var symbolizer = new ol.style.Icon({
+        height: 10,
+        width: 20,
+        url: 'http://example.com/1.png'
+      });
+
+      var literal = symbolizer.createLiteral(ol.geom.GeometryType.POINT);
+      expect(literal).to.be.a(ol.style.IconLiteral);
+      expect(literal.zIndex).to.be(0);
+    });
+
+    it('casts zIndex to number', function() {
+      var symbolizer = new ol.style.Icon({
+        zIndex: ol.expr.parse('zIndex'),
+        width: 10,
+        url: 'http://example.com/1.png'
+      });
+
+      var feature = new ol.Feature({
+        zIndex: '42',
+        geometry: new ol.geom.Point([1, 2])
+      });
+
+      var literal = symbolizer.createLiteral(feature);
+      expect(literal).to.be.a(ol.style.IconLiteral);
+      expect(literal.zIndex).to.be(42);
+    });
+
   });
 
   describe('#getHeight()', function() {
diff --git a/test/spec/ol/style/lineliteral.test.js b/test/spec/ol/style/lineliteral.test.js
index 19349064bc..323c5e17af 100644
--- a/test/spec/ol/style/lineliteral.test.js
+++ b/test/spec/ol/style/lineliteral.test.js
@@ -8,27 +8,32 @@ describe('ol.style.LineLiteral', function() {
       var literal = new ol.style.LineLiteral({
         width: 3,
         color: '#BADA55',
-        opacity: 1
+        opacity: 1,
+        zIndex: 0
       });
       var equalLiteral = new ol.style.LineLiteral({
         color: '#BADA55',
         width: 3,
-        opacity: 1
+        opacity: 1,
+        zIndex: 0
       });
       var differentColor = new ol.style.LineLiteral({
         width: 3,
         color: '#ff0000',
-        opacity: 1
+        opacity: 1,
+        zIndex: 0
       });
       var differentWidth = new ol.style.LineLiteral({
         width: 3.5,
         color: '#BADA55',
-        opacity: 1
+        opacity: 1,
+        zIndex: 0
       });
       var differentOpacity = new ol.style.LineLiteral({
         width: 3,
         color: '#BADA55',
-        opacity: 0.5
+        opacity: 0.5,
+        zIndex: 0
       });
       var differentZIndex = new ol.style.LineLiteral({
         width: 3,
diff --git a/test/spec/ol/style/polygonliteral.test.js b/test/spec/ol/style/polygonliteral.test.js
index 4471ed4db6..642af45f48 100644
--- a/test/spec/ol/style/polygonliteral.test.js
+++ b/test/spec/ol/style/polygonliteral.test.js
@@ -10,49 +10,56 @@ describe('ol.style.PolygonLiteral', function() {
         strokeColor: '#013',
         strokeOpacity: 0.4,
         fillColor: '#BADA55',
-        fillOpacity: 0.3
+        fillOpacity: 0.3,
+        zIndex: 0
       });
       var equalLiteral = new ol.style.PolygonLiteral({
         strokeWidth: 3,
         strokeColor: '#013',
         strokeOpacity: 0.4,
         fillColor: '#BADA55',
-        fillOpacity: 0.3
+        fillOpacity: 0.3,
+        zIndex: 0
       });
       var differentStrokeWidth = new ol.style.PolygonLiteral({
         strokeWidth: 5,
         strokeColor: '#013',
         strokeOpacity: 0.4,
         fillColor: '#BADA55',
-        fillOpacity: 0.3
+        fillOpacity: 0.3,
+        zIndex: 0
       });
       var differentStrokeColor = new ol.style.PolygonLiteral({
         strokeWidth: 3,
         strokeColor: '#ffff00',
         strokeOpacity: 0.4,
         fillColor: '#BADA55',
-        fillOpacity: 0.3
+        fillOpacity: 0.3,
+        zIndex: 0
       });
       var differentStrokeOpacity = new ol.style.PolygonLiteral({
         strokeWidth: 3,
         strokeColor: '#013',
         strokeOpacity: 0.41,
         fillColor: '#BADA55',
-        fillOpacity: 0.3
+        fillOpacity: 0.3,
+        zIndex: 0
       });
       var differentFillColor = new ol.style.PolygonLiteral({
         strokeWidth: 3,
         strokeColor: '#013',
         strokeOpacity: 0.4,
         fillColor: '#00ffff',
-        fillOpacity: 0.3
+        fillOpacity: 0.3,
+        zIndex: 0
       });
       var differentFillOpacity = new ol.style.PolygonLiteral({
         strokeWidth: 3,
         strokeColor: '#013',
         strokeOpacity: 0.4,
         fillColor: '#BADA55',
-        fillOpacity: 0.31
+        fillOpacity: 0.31,
+        zIndex: 0
       });
       var differentZIndex = new ol.style.PolygonLiteral({
         strokeWidth: 3,
diff --git a/test/spec/ol/style/shapeliteral.test.js b/test/spec/ol/style/shapeliteral.test.js
index 68768be103..f5af82b807 100644
--- a/test/spec/ol/style/shapeliteral.test.js
+++ b/test/spec/ol/style/shapeliteral.test.js
@@ -12,7 +12,8 @@ describe('ol.style.ShapeLiteral', function() {
         fillOpacity: 0.9,
         strokeColor: '#013',
         strokeOpacity: 0.8,
-        strokeWidth: 3
+        strokeWidth: 3,
+        zIndex: 0
       });
       var equalLiteral = new ol.style.ShapeLiteral({
         type: ol.style.ShapeType.CIRCLE,
@@ -21,7 +22,8 @@ describe('ol.style.ShapeLiteral', function() {
         fillOpacity: 0.9,
         strokeColor: '#013',
         strokeOpacity: 0.8,
-        strokeWidth: 3
+        strokeWidth: 3,
+        zIndex: 0
       });
       var differentSize = new ol.style.ShapeLiteral({
         type: ol.style.ShapeType.CIRCLE,
@@ -30,7 +32,8 @@ describe('ol.style.ShapeLiteral', function() {
         fillOpacity: 0.9,
         strokeColor: '#013',
         strokeOpacity: 0.8,
-        strokeWidth: 3
+        strokeWidth: 3,
+        zIndex: 0
       });
       var differentFillColor = new ol.style.ShapeLiteral({
         type: ol.style.ShapeType.CIRCLE,
@@ -39,7 +42,8 @@ describe('ol.style.ShapeLiteral', function() {
         fillOpacity: 0.9,
         strokeColor: '#013',
         strokeOpacity: 0.8,
-        strokeWidth: 3
+        strokeWidth: 3,
+        zIndex: 0
       });
       var differentFillOpacity = new ol.style.ShapeLiteral({
         type: ol.style.ShapeType.CIRCLE,
@@ -48,7 +52,8 @@ describe('ol.style.ShapeLiteral', function() {
         fillOpacity: 0.8,
         strokeColor: '#013',
         strokeOpacity: 0.8,
-        strokeWidth: 3
+        strokeWidth: 3,
+        zIndex: 0
       });
       var differentStrokeColor = new ol.style.ShapeLiteral({
         type: ol.style.ShapeType.CIRCLE,
@@ -57,7 +62,8 @@ describe('ol.style.ShapeLiteral', function() {
         fillOpacity: 0.9,
         strokeColor: '#ffffff',
         strokeOpacity: 0.8,
-        strokeWidth: 3
+        strokeWidth: 3,
+        zIndex: 0
       });
       var differentStrokeOpacity = new ol.style.ShapeLiteral({
         type: ol.style.ShapeType.CIRCLE,
@@ -66,7 +72,8 @@ describe('ol.style.ShapeLiteral', function() {
         fillOpacity: 0.9,
         strokeColor: '#013',
         strokeOpacity: 0.7,
-        strokeWidth: 3
+        strokeWidth: 3,
+        zIndex: 0
       });
       var differentStrokeWidth = new ol.style.ShapeLiteral({
         type: ol.style.ShapeType.CIRCLE,
@@ -75,7 +82,8 @@ describe('ol.style.ShapeLiteral', function() {
         fillOpacity: 0.9,
         strokeColor: '#013',
         strokeOpacity: 0.8,
-        strokeWidth: 4
+        strokeWidth: 4,
+        zIndex: 0
       });
       var differentZIndex = new ol.style.ShapeLiteral({
         type: ol.style.ShapeType.CIRCLE,
diff --git a/test/spec/ol/style/shapesymbolizer.test.js b/test/spec/ol/style/shapesymbolizer.test.js
index 7b4bbce3ee..d6c1b56450 100644
--- a/test/spec/ol/style/shapesymbolizer.test.js
+++ b/test/spec/ol/style/shapesymbolizer.test.js
@@ -58,7 +58,7 @@ describe('ol.style.Shape', function() {
       expect(literal).to.be.a(ol.style.ShapeLiteral);
       expect(literal.size).to.be(42);
       expect(literal.fillOpacity).to.be(0.4);
-      expect(literal.zIndex).to.be(undefined);
+      expect(literal.zIndex).to.be(0);
     });
 
     it('can be called without a feature', function() {
@@ -185,6 +185,24 @@ describe('ol.style.Shape', function() {
       expect(literal.zIndex).to.be(-2);
     });
 
+    it('casts zIndex to number', function() {
+      var symbolizer = new ol.style.Shape({
+        fill: new ol.style.Fill({
+          color: '#BADA55'
+        }),
+        zIndex: ol.expr.parse('zIndex')
+      });
+
+      var feature = new ol.Feature({
+        zIndex: '42',
+        geometry: new ol.geom.Point([1, 2])
+      });
+
+      var literal = symbolizer.createLiteral(feature);
+      expect(literal).to.be.a(ol.style.ShapeLiteral);
+      expect(literal.zIndex).to.be(42);
+    });
+
   });
 
   describe('#getFill()', function() {
diff --git a/test/spec/ol/style/strokesymbolizer.test.js b/test/spec/ol/style/strokesymbolizer.test.js
index 4d28fdfc69..bd4890fe8c 100644
--- a/test/spec/ol/style/strokesymbolizer.test.js
+++ b/test/spec/ol/style/strokesymbolizer.test.js
@@ -49,7 +49,7 @@ describe('ol.style.Stroke', function() {
       expect(literal).to.be.a(ol.style.LineLiteral);
       expect(literal.opacity).to.be(42 / 100);
       expect(literal.width).to.be(1.5);
-      expect(literal.zIndex).to.be(undefined);
+      expect(literal.zIndex).to.be(0);
     });
 
     it('applies the default values', function() {
@@ -60,6 +60,7 @@ describe('ol.style.Stroke', function() {
       expect(literal.color).to.be('#696969');
       expect(literal.opacity).to.be(0.75);
       expect(literal.width).to.be(1.5);
+      expect(literal.zIndex).to.be(0);
     });
 
   });
diff --git a/test/spec/ol/style/style.test.js b/test/spec/ol/style/style.test.js
index 18fdb5e8c8..5bc1314f36 100644
--- a/test/spec/ol/style/style.test.js
+++ b/test/spec/ol/style/style.test.js
@@ -194,12 +194,14 @@ describe('ol.style.Style', function() {
       var literals = [
         new ol.style.PolygonLiteral({
           fillColor: '#ff0000',
-          fillOpacity: 0.5
+          fillOpacity: 0.5,
+          zIndex: 0
         }),
         new ol.style.PolygonLiteral({
           strokeColor: '#00ff00',
           strokeOpacity: 0.6,
-          strokeWidth: 3
+          strokeWidth: 3,
+          zIndex: 0
         })
       ];
 
@@ -221,12 +223,14 @@ describe('ol.style.Style', function() {
           fillOpacity: 0.5,
           strokeColor: '#00ff00',
           strokeOpacity: 0.6,
-          strokeWidth: 3
+          strokeWidth: 3,
+          zIndex: 0
         }),
         new ol.style.PolygonLiteral({
           strokeColor: '#0000ff',
           strokeOpacity: 0.7,
-          strokeWidth: 1
+          strokeWidth: 1,
+          zIndex: 0
         })
       ];
 
@@ -253,18 +257,21 @@ describe('ol.style.Style', function() {
         new ol.style.PolygonLiteral({
           strokeColor: '#00ff00',
           strokeOpacity: 0.6,
-          strokeWidth: 3
+          strokeWidth: 3,
+          zIndex: 0
         }),
         new ol.style.PolygonLiteral({
           fillColor: '#ff0000',
-          fillOpacity: 0.5
+          fillOpacity: 0.5,
+          zIndex: 0
         }),
         new ol.style.TextLiteral({
           color: '#ffffff',
           fontFamily: 'Arial',
           fontSize: 11,
           text: 'Test',
-          opacity: 0.5
+          opacity: 0.5,
+          zIndex: 0
         })
       ];
 
diff --git a/test/spec/ol/style/textliteral.test.js b/test/spec/ol/style/textliteral.test.js
index 8a4d3010c4..b3b945675a 100644
--- a/test/spec/ol/style/textliteral.test.js
+++ b/test/spec/ol/style/textliteral.test.js
@@ -10,49 +10,56 @@ describe('ol.style.TextLiteral', function() {
         fontFamily: 'Arial',
         fontSize: 11,
         text: 'Test',
-        opacity: 0.5
+        opacity: 0.5,
+        zIndex: 0
       });
       var equalLiteral = new ol.style.TextLiteral({
         color: '#ff0000',
         fontFamily: 'Arial',
         fontSize: 11,
         text: 'Test',
-        opacity: 0.5
+        opacity: 0.5,
+        zIndex: 0
       });
-      var differentLiteral1 = new ol.style.TextLiteral({
+      var differentColor = new ol.style.TextLiteral({
         color: '#0000ff',
         fontFamily: 'Arial',
         fontSize: 11,
         text: 'Test',
-        opacity: 0.5
+        opacity: 0.5,
+        zIndex: 0
       });
-      var differentLiteral2 = new ol.style.TextLiteral({
+      var differentFontFamily = new ol.style.TextLiteral({
         color: '#ff0000',
         fontFamily: 'Dingbats',
         fontSize: 11,
         text: 'Test',
-        opacity: 0.5
+        opacity: 0.5,
+        zIndex: 0
       });
-      var differentLiteral3 = new ol.style.TextLiteral({
+      var differentFontSize = new ol.style.TextLiteral({
         color: '#ff0000',
         fontFamily: 'Arial',
         fontSize: 12,
         text: 'Test',
-        opacity: 0.5
+        opacity: 0.5,
+        zIndex: 0
       });
-      var differentLiteral4 = new ol.style.TextLiteral({
+      var differentOpacity = new ol.style.TextLiteral({
         color: '#ff0000',
         fontFamily: 'Arial',
         fontSize: 11,
         text: 'Test',
-        opacity: 0.6
+        opacity: 0.6,
+        zIndex: 0
       });
       var equalLiteral2 = new ol.style.TextLiteral({
         color: '#ff0000',
         fontFamily: 'Arial',
         fontSize: 11,
         text: 'Text is not compared for equality',
-        opacity: 0.5
+        opacity: 0.5,
+        zIndex: 0
       });
       var differentZIndex = new ol.style.TextLiteral({
         color: '#ff0000',
@@ -63,10 +70,10 @@ describe('ol.style.TextLiteral', function() {
         zIndex: 3
       });
       expect(literal.equals(equalLiteral)).to.be(true);
-      expect(literal.equals(differentLiteral1)).to.be(false);
-      expect(literal.equals(differentLiteral2)).to.be(false);
-      expect(literal.equals(differentLiteral3)).to.be(false);
-      expect(literal.equals(differentLiteral4)).to.be(false);
+      expect(literal.equals(differentColor)).to.be(false);
+      expect(literal.equals(differentFontFamily)).to.be(false);
+      expect(literal.equals(differentFontSize)).to.be(false);
+      expect(literal.equals(differentOpacity)).to.be(false);
       expect(literal.equals(equalLiteral2)).to.be(true);
       expect(literal.equals(differentZIndex)).to.be(false);
     });