Right grate fixed loft (6)
I believe the answer is:
garret
'loft' is the definition.
('garret' can be a synonym of 'loft')
'right grate fixed' is the wordplay.
'right' becomes 'r' (common abbreviation).
'fixed' is an anagram indicator.
'r'+'grate'='rgrate'
'rgrate' anagrammed gives 'GARRET'.
(Other definitions for garret that I've seen before include "Upper room" , "Attic, home of struggling artist?" , "Room on the top floor of a house" , "Room under the roof" , "Cheap top-floor room" .)