diff --git a/src/Psalm/Checker/Statements/ExpressionChecker.php b/src/Psalm/Checker/Statements/ExpressionChecker.php
index d87b0df74..767328f71 100644
--- a/src/Psalm/Checker/Statements/ExpressionChecker.php
+++ b/src/Psalm/Checker/Statements/ExpressionChecker.php
@@ -121,17 +121,28 @@ class ExpressionChecker
             $stmt->inferredType = Type::getInt();
         } elseif ($stmt instanceof PhpParser\Node\Scalar\DNumber) {
             $stmt->inferredType = Type::getFloat();
-        } elseif ($stmt instanceof PhpParser\Node\Expr\UnaryMinus) {
-            if (self::analyze($statements_checker, $stmt->expr, $context) === false) {
-                return false;
-            }
-            $stmt->inferredType = isset($stmt->expr->inferredType) ? $stmt->expr->inferredType : null;
-        } elseif ($stmt instanceof PhpParser\Node\Expr\UnaryPlus) {
+        } elseif ($stmt instanceof PhpParser\Node\Expr\UnaryMinus ||
+            $stmt instanceof PhpParser\Node\Expr\UnaryPlus
+        ) {
             if (self::analyze($statements_checker, $stmt->expr, $context) === false) {
                 return false;
             }
 
-            $stmt->inferredType = isset($stmt->expr->inferredType) ? $stmt->expr->inferredType : null;
+            if (!isset($stmt->expr->inferredType)) {
+                $stmt->inferredType = new Type\Union([new TInt, new TFloat]);
+            } else {
+                if ($stmt->expr->inferredType->hasInt() || $stmt->expr->inferredType->hasFloat()) {
+                    if (!$stmt->expr->inferredType->hasFloat()) {
+                        $stmt->inferredType = Type::getInt();
+                    } elseif (!$stmt->expr->inferredType->hasInt()) {
+                        $stmt->inferredType = Type::getFloat();
+                    } else {
+                        $stmt->inferredType = new Type\Union([new TInt, new TFloat]);
+                    }
+                } else {
+                    $stmt->inferredType = new Type\Union([new TInt, new TFloat]);
+                }
+            }
         } elseif ($stmt instanceof PhpParser\Node\Expr\Isset_) {
             self::analyzeIsset($statements_checker, $stmt, $context);
             $stmt->inferredType = Type::getBool();
diff --git a/tests/TypeTest.php b/tests/TypeTest.php
index 7a83d62eb..e28b5d29d 100644
--- a/tests/TypeTest.php
+++ b/tests/TypeTest.php
@@ -1924,4 +1924,20 @@ class TypeTest extends PHPUnit_Framework_TestCase
         $context = new Context();
         $file_checker->visitAndAnalyzeMethods($context);
     }
+
+    /**
+     * @return void
+     */
+    public function testIsIntOnUnaryPlus()
+    {
+        $stmts = self::$parser->parse('<?php
+        $a = +"5";
+        if (!is_int($a)) {
+        }
+        ');
+
+        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
+        $context = new Context();
+        $file_checker->visitAndAnalyzeMethods($context);
+    }
 }