diff --git a/composer.json b/composer.json
index 28606d9..a6df5a1 100644
--- a/composer.json
+++ b/composer.json
@@ -28,7 +28,8 @@
   },
   "require-dev": {
     "squizlabs/php_codesniffer": "^2.5",
-    "phpunit/phpunit": "^5.7|^6.0"
+    "phpunit/phpunit": "^5.7|^6.0",
+    "php-http/psr7-integration-tests": "dev-master"
   },
   "provide": {
     "psr/http-message-implementation": "1.0"
diff --git a/src/Uri.php b/src/Uri.php
index afac69c..9a589af 100644
--- a/src/Uri.php
+++ b/src/Uri.php
@@ -112,7 +112,7 @@ public function __construct(
         $password = ''
     ) {
         $this->scheme = $this->filterScheme($scheme);
-        $this->host = $host;
+        $this->host = strtolower($host);
         $this->port = $this->filterPort($port);
         $this->path = empty($path) ? '/' : $this->filterPath($path);
         $this->query = $this->filterQuery($query);
@@ -390,7 +390,7 @@ public function getHost()
     public function withHost($host)
     {
         $clone = clone $this;
-        $clone->host = $host;
+        $clone->host = strtolower($host);
 
         return $clone;
     }
diff --git a/tests/Integration/BaseTestFactories.php b/tests/Integration/BaseTestFactories.php
new file mode 100644
index 0000000..da6cb85
--- /dev/null
+++ b/tests/Integration/BaseTestFactories.php
@@ -0,0 +1,51 @@
+<?php
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @link      https://github.com/slimphp/Slim-Http
+ * @copyright Copyright (c) 2011-2017 Josh Lockhart
+ * @license   https://github.com/slimphp/Slim-Http/blob/master/LICENSE (MIT License)
+ */
+namespace Slim\Tests\Http\Integration;
+
+use Slim\Http\Stream;
+use Slim\Http\UploadedFile;
+use Slim\Http\Uri;
+
+trait BaseTestFactories
+{
+
+    /**
+     * @param $uri
+     * @return Uri
+     */
+    protected function buildUri($uri)
+    {
+        return Uri::createFromString($uri);
+    }
+
+    /**
+     * @param $data
+     * @return Stream
+     */
+    protected function buildStream($data)
+    {
+        if (!is_resource($data)) {
+            $h = fopen('php://temp', 'w+');
+            fwrite($h, $data);
+
+            $data = $h;
+        }
+
+        return new Stream($data);
+    }
+
+    /**
+     * @param $data
+     * @return UploadedFile
+     */
+    protected function buildUploadableFile($data)
+    {
+        return new UploadedFile($data);
+    }
+}
diff --git a/tests/Integration/ResponseTest.php b/tests/Integration/ResponseTest.php
new file mode 100644
index 0000000..5ed44f3
--- /dev/null
+++ b/tests/Integration/ResponseTest.php
@@ -0,0 +1,26 @@
+<?php
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @link      https://github.com/slimphp/Slim-Http
+ * @copyright Copyright (c) 2011-2017 Josh Lockhart
+ * @license   https://github.com/slimphp/Slim-Http/blob/master/LICENSE (MIT License)
+ */
+namespace Slim\Tests\Http\Integration;
+
+use Http\Psr7Test\ResponseIntegrationTest;
+use Psr\Http\Message\ResponseInterface;
+use Slim\Http\Response;
+
+class ResponseTest extends ResponseIntegrationTest
+{
+    use BaseTestFactories;
+
+    /**
+     * @return ResponseInterface that is used in the tests
+     */
+    public function createSubject()
+    {
+        return new Response();
+    }
+}
diff --git a/tests/Integration/ServerRequestTest.php b/tests/Integration/ServerRequestTest.php
new file mode 100644
index 0000000..263f485
--- /dev/null
+++ b/tests/Integration/ServerRequestTest.php
@@ -0,0 +1,27 @@
+<?php
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @link      https://github.com/slimphp/Slim-Http
+ * @copyright Copyright (c) 2011-2017 Josh Lockhart
+ * @license   https://github.com/slimphp/Slim-Http/blob/master/LICENSE (MIT License)
+ */
+namespace Slim\Tests\Http\Integration;
+
+use Psr\Http\Message\ServerRequestInterface;
+use Slim\Http\Headers;
+use Slim\Http\Request;
+use Http\Psr7Test\ServerRequestIntegrationTest;
+
+class ServerRequestTest extends ServerRequestIntegrationTest
+{
+    use BaseTestFactories;
+
+    /**
+     * @return ServerRequestInterface that is used in the tests
+     */
+    public function createSubject()
+    {
+        return new Request('GET', $this->buildUri('/'), new Headers(), [], $_SERVER, $this->buildStream(''));
+    }
+}
diff --git a/tests/Integration/StreamTest.php b/tests/Integration/StreamTest.php
new file mode 100644
index 0000000..0de6f4c
--- /dev/null
+++ b/tests/Integration/StreamTest.php
@@ -0,0 +1,38 @@
+<?php
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @link      https://github.com/slimphp/Slim-Http
+ * @copyright Copyright (c) 2011-2017 Josh Lockhart
+ * @license   https://github.com/slimphp/Slim-Http/blob/master/LICENSE (MIT License)
+ */
+namespace Slim\Tests\Http\Integration;
+
+use Http\Psr7Test\StreamIntegrationTest;
+use Psr\Http\Message\StreamInterface;
+use Slim\Http\Stream;
+
+class StreamTest extends StreamIntegrationTest
+{
+    use BaseTestFactories;
+
+    /**
+     * @param string|resource|StreamInterface $data
+     *
+     * @return StreamInterface
+     */
+    public function createStream($data)
+    {
+        if ($data instanceof StreamInterface) {
+            return $data;
+        } elseif (is_resource($data)) {
+            return new Stream($data);
+        } elseif (is_string($data)) {
+            $s = fopen('php://temp', 'w+');
+            fwrite($s, $data);
+            return new Stream($s);
+        }
+
+        throw new \InvalidArgumentException();
+    }
+}
diff --git a/tests/Integration/UploadedFileTest.php b/tests/Integration/UploadedFileTest.php
new file mode 100644
index 0000000..33f6dbd
--- /dev/null
+++ b/tests/Integration/UploadedFileTest.php
@@ -0,0 +1,26 @@
+<?php
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @link      https://github.com/slimphp/Slim-Http
+ * @copyright Copyright (c) 2011-2017 Josh Lockhart
+ * @license   https://github.com/slimphp/Slim-Http/blob/master/LICENSE (MIT License)
+ */
+namespace Slim\Tests\Http\Integration;
+
+use Http\Psr7Test\UploadedFileIntegrationTest;
+use Psr\Http\Message\UploadedFileInterface;
+use Slim\Http\UploadedFile;
+
+class UploadedFileTest extends UploadedFileIntegrationTest
+{
+    use BaseTestFactories;
+
+    /**
+     * @return UploadedFileInterface that is used in the tests
+     */
+    public function createSubject()
+    {
+        return new UploadedFile(tmpfile());
+    }
+}
diff --git a/tests/Integration/UriTest.php b/tests/Integration/UriTest.php
new file mode 100644
index 0000000..ca0c280
--- /dev/null
+++ b/tests/Integration/UriTest.php
@@ -0,0 +1,28 @@
+<?php
+/**
+ * Slim Framework (https://slimframework.com)
+ *
+ * @link      https://github.com/slimphp/Slim-Http
+ * @copyright Copyright (c) 2011-2017 Josh Lockhart
+ * @license   https://github.com/slimphp/Slim-Http/blob/master/LICENSE (MIT License)
+ */
+namespace Slim\Tests\Http\Integration;
+
+use Http\Psr7Test\UriIntegrationTest;
+use Psr\Http\Message\UriInterface;
+use Slim\Http\Uri;
+
+class UriTest extends UriIntegrationTest
+{
+    use BaseTestFactories;
+
+    /**
+     * @param string $uri
+     *
+     * @return UriInterface
+     */
+    public function createUri($uri)
+    {
+        return Uri::createFromString($uri);
+    }
+}