diff --git a/XMonad/Layout/IfMax.hs b/XMonad/Layout/IfMax.hs
index 58af06c0..77a16cfb 100644
--- a/XMonad/Layout/IfMax.hs
+++ b/XMonad/Layout/IfMax.hs
@@ -14,7 +14,7 @@
 --
 -----------------------------------------------------------------------------
 
-{-# LANGUAGE FlexibleInstances, MultiParamTypeClasses #-}
+{-# LANGUAGE FlexibleInstances, MultiParamTypeClasses, FlexibleContexts #-}
 
 module XMonad.Layout.IfMax
     ( -- * Usage
@@ -24,6 +24,9 @@ module XMonad.Layout.IfMax
     ) where
 
 import Control.Applicative((<$>))
+import Control.Arrow
+import qualified Data.List as L
+import qualified Data.Map  as M
 import Data.Maybe
 
 import XMonad
@@ -48,25 +51,25 @@ import qualified XMonad.StackSet as W
 data IfMax l1 l2 w = IfMax Int (l1 w) (l2 w)
   deriving (Read, Show)
 
-instance (LayoutClass l1 a, LayoutClass l2 a) => LayoutClass (IfMax l1 l2) a where
+instance (LayoutClass l1 Window, LayoutClass l2 Window) => LayoutClass (IfMax l1 l2) Window where
 
-  runLayout (W.Workspace _ (IfMax n l1 l2) s) rect = arrange (W.integrate' s)
+  runLayout (W.Workspace _ (IfMax n l1 l2) s) rect = withWindowSet $ \ws -> arrange (W.integrate' s) (M.keys . W.floating $ ws)
     where
-      arrange [] = do l1' <- maybe l1 id `fmap` handleMessage l1 (SomeMessage ReleaseResources)
-                      l2' <- maybe l2 id `fmap` handleMessage l2 (SomeMessage ReleaseResources)
-                      return ([], Just $ IfMax n l1' l2')
-      arrange ws | length ws <= n = do
+      arrange [] _ = do l1' <- maybe l1 id `fmap` handleMessage l1 (SomeMessage ReleaseResources)
+                        l2' <- maybe l2 id `fmap` handleMessage l2 (SomeMessage ReleaseResources)
+                        return ([], Just $ IfMax n l1' l2')
+      arrange ws fw | length (ws L.\\ fw) <= n = do
                                     (wrs, ml1') <- runLayout (W.Workspace "" l1 s) rect
                                     let l1' = fromMaybe l1 ml1'
                                     return (wrs, Just $ IfMax n l1' l2)
-                 | otherwise      = do
+                    | otherwise      = do
                                     (wrs, ml2') <- runLayout (W.Workspace "" l2 s) rect
                                     let l2' = fromMaybe l2 ml2'
                                     return (wrs, Just $ IfMax n l1 l2')
 
   handleMessage (IfMax n l1 l2) m = do
-      len <- gets (length . W.integrate' . W.stack . W.workspace . W.current . windowset)
-      if len <= n
+      (allWindows, floatingWindows) <- gets ((W.integrate' . W.stack . W.workspace . W.current &&& M.keys . W.floating) . windowset)
+      if length (allWindows L.\\ floatingWindows) <= n
         then do
           l1' <- handleMessage l1 m
           return $ flip (IfMax n) l2 <$> l1'