diff --git a/src/window.c b/src/window.c
index de85739..9fe56b1 100644
--- a/src/window.c
+++ b/src/window.c
@@ -688,6 +688,8 @@
     int		before;
     int		minwidth;
     int		minheight;
+    int		wmw1;
+    int		wmh1;
 
     if (flags & WSP_TOP)
 	oldwin = firstwin;
@@ -722,19 +724,22 @@
 	 * Check if we are able to split the current window and compute its
 	 * width.
 	 */
-	needed = p_wmw + 1;
+	/* Current window requires at least 1 space. */
+	wmw1 = (p_wmw == 0 ? 1 : p_wmw);
+	needed = wmw1 + 1;
 	if (flags & WSP_ROOM)
-	    needed += p_wiw - p_wmw;
+	    needed += p_wiw - wmw1;
 	if (p_ea || (flags & (WSP_BOT | WSP_TOP)))
 	{
-	    minwidth = frame_minwidth(topframe, NULL);
+	    minwidth = frame_minwidth(topframe, NOWIN);
 	    available = topframe->fr_width;
 	    needed += minwidth;
 	}
 	else
 	{
-	    minwidth = frame_minwidth(oldwin->w_frame, NULL);
-	    available = oldwin->w_width;
+	    minwidth = frame_minwidth(oldwin->w_frame, NOWIN);
+	    available = oldwin->w_frame->fr_width;
+	    needed += minwidth;
 	}
 	if (available < needed && new_wp == NULL)
 	{
@@ -743,12 +748,10 @@
 	}
 	if (new_size == 0)
 	    new_size = oldwin->w_width / 2;
-	if (new_size > oldwin->w_width - p_wmw - 1)
-	    new_size = oldwin->w_width - p_wmw - 1;
 	if (new_size > available - minwidth - 1)
 	    new_size = available - minwidth - 1;
-	if (new_size < p_wmw)
-	    new_size = p_wmw;
+	if (new_size < wmw1)
+	    new_size = wmw1;
 
 	/* if it doesn't fit in the current window, need win_equal() */
 	if (oldwin->w_width - new_size - 1 < p_wmw)
@@ -789,20 +792,22 @@
 	 * Check if we are able to split the current window and compute its
 	 * height.
 	 */
-	needed = p_wmh + STATUS_HEIGHT + need_status;
+	/* Current window requires at least 1 space. */
+	wmh1 = (p_wmh == 0 ? 1 : p_wmh);
+	needed = wmh1 + STATUS_HEIGHT;
 	if (flags & WSP_ROOM)
-	    needed += p_wh - p_wmh;
+	    needed += p_wh - wmh1;
 	if (p_ea || (flags & (WSP_BOT | WSP_TOP)))
 	{
-	    minheight = frame_minheight(topframe, NULL);
+	    minheight = frame_minheight(topframe, NOWIN) + need_status;
 	    available = topframe->fr_height;
 	    needed += minheight;
 	}
 	else
 	{
-	    minheight = frame_minheight(oldwin->w_frame, NULL);
-	    available = oldwin->w_height;
-	    needed += p_wmh;
+	    minheight = frame_minheight(oldwin->w_frame, NOWIN) + need_status;
+	    available = oldwin->w_frame->fr_height;
+	    needed += minheight;
 	}
 	if (available < needed && new_wp == NULL)
 	{
@@ -817,13 +822,10 @@
 	}
 	if (new_size == 0)
 	    new_size = oldwin_height / 2;
-
-	if (new_size > oldwin_height - p_wmh - STATUS_HEIGHT)
-	    new_size = oldwin_height - p_wmh - STATUS_HEIGHT;
 	if (new_size > available - minheight - STATUS_HEIGHT)
 	    new_size = available - minheight - STATUS_HEIGHT;
-	if (new_size < p_wmh)
-	    new_size = p_wmh;
+	if (new_size < wmh1)
+	    new_size = wmh1;
 
 	/* if it doesn't fit in the current window, need win_equal() */
 	if (oldwin_height - new_size - STATUS_HEIGHT < p_wmh)