Barn's upper space (4)
I believe the answer is:
loft
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">barn's upper space</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for loft that I've seen before include "Raised shelter for pigeons" , "Storage space under a roof" , "Elevation" , "Space under barn roof for storing hay" , "Shelter for racing pigeons" .)