Tell sir to change framework (7)
I believe the answer is:
trellis
'framework' is the definition.
(I know that trellis is a type of fretwork)
'tell sir to change' is the wordplay.
'to change' is an anagram indicator.
'tell'+'sir'='tellsir'
'tellsir' anagrammed gives 'TRELLIS'.
(Other definitions for trellis that I've seen before include "Train for plants" , "Garden frame or screen" , "Framework supporting climbers" , "Garden climbing frame" , "latticework in the garden" .)