diff --git a/CHANGES.md b/CHANGES.md
index 7ef2852..12b741d 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -51,6 +51,9 @@
   * Added `withUnfocused` function to `XMonad.Operations`, allowing for `X`
     operations to be applied to unfocused windows.
 
+  * Added `willFloat` function to `XMonad.ManageHooks` to detect whether the
+    (about to be) managed window will be a floating window or not
+
 [these build scripts]: https://github.com/xmonad/xmonad-testing/tree/master/build-scripts
 
 ### Bug Fixes
diff --git a/src/XMonad/ManageHook.hs b/src/XMonad/ManageHook.hs
index 1a21f2a..fb28d10 100644
--- a/src/XMonad/ManageHook.hs
+++ b/src/XMonad/ManageHook.hs
@@ -27,7 +27,7 @@ import Control.Monad.Reader
 import Data.Maybe
 import Data.Monoid
 import qualified XMonad.StackSet as W
-import XMonad.Operations (floatLocation, reveal)
+import XMonad.Operations (floatLocation, reveal, isFixedSizeOrTransient)
 
 -- | Lift an 'X' action to a 'Query'.
 liftX :: X a -> Query a
@@ -106,6 +106,10 @@ getStringProperty d w p = do
   md <- io $ getWindowProperty8 d a w
   return $ fmap (map (toEnum . fromIntegral)) md
 
+-- | Return whether the window will be a floating window or not
+willFloat :: Query Bool
+willFloat = ask >>= \w -> liftX $ withDisplay $ \d -> isFixedSizeOrTransient d w
+
 -- | Modify the 'WindowSet' with a pure function.
 doF :: (s -> s) -> Query (Endo s)
 doF = return . Endo
diff --git a/src/XMonad/Operations.hs b/src/XMonad/Operations.hs
index 2422347..3e43fc9 100644
--- a/src/XMonad/Operations.hs
+++ b/src/XMonad/Operations.hs
@@ -18,7 +18,7 @@ module XMonad.Operations (
     manage, unmanage, killWindow, kill, isClient,
     setInitialProperties, setWMState, setWindowBorderWithFallback,
     hide, reveal, tileWindow,
-    setTopFocus, focus,
+    setTopFocus, focus, isFixedSizeOrTransient,
 
     -- * Manage Windows
     windows, refresh, rescreen, modifyWindowSet, windowBracket, windowBracket_, clearEvents, getCleanedScreenInfo,
@@ -78,6 +78,16 @@ import Graphics.X11.Xlib.Extras
 -- ---------------------------------------------------------------------
 -- Window manager operations
 
+-- | Detect whether a window has fixed size or is transient. This check
+-- can be used to determine whether the window should be floating or not
+--
+isFixedSizeOrTransient :: Display -> Window -> X Bool
+isFixedSizeOrTransient d w = do
+  sh <- io $ getWMNormalHints d w
+  let isFixedSize = isJust (sh_min_size sh) && sh_min_size sh == sh_max_size sh
+  isTransient <- isJust <$> io (getTransientForHint d w)
+  return (isFixedSize || isTransient)
+
 -- |
 -- Add a new window to be managed in the current workspace.
 -- Bring it into focus.
@@ -87,10 +97,8 @@ import Graphics.X11.Xlib.Extras
 --
 manage :: Window -> X ()
 manage w = whenX (not <$> isClient w) $ withDisplay $ \d -> do
-    sh <- io $ getWMNormalHints d w
 
-    let isFixedSize = sh_min_size sh /= Nothing && sh_min_size sh == sh_max_size sh
-    isTransient <- isJust <$> io (getTransientForHint d w)
+    shouldFloat <- isFixedSizeOrTransient d w
 
     rr <- snd `fmap` floatLocation w
     -- ensure that float windows don't go over the edge of the screen
@@ -98,7 +106,7 @@ manage w = whenX (not <$> isClient w) $ withDisplay $ \d -> do
                                               = W.RationalRect (0.5 - wid/2) (0.5 - h/2) wid h
         adjust r = r
 
-        f ws | isFixedSize || isTransient = W.float w (adjust rr) . W.insertUp w . W.view i $ ws
+        f ws | shouldFloat                = W.float w (adjust rr) . W.insertUp w . W.view i $ ws
              | otherwise                  = W.insertUp w ws
             where i = W.tag $ W.workspace $ W.current ws