Grill room on left close to patisserie (7)
I believe the answer is:
lattice
'grill' is the definition.
(I've seen this before)
'room on left close to patisserie' is the wordplay.
'room' becomes 'attic' (I've seen this before**).
'on' means one lot of letters go next to another.
'left' becomes 'l' (common abbreviation).
'close to' suggests the final letters (the close/ending of).
The last letter of 'patisserie' is 'e'.
'attic' after 'l' is 'lattic'.
'lattic'+'e'='LATTICE'
(Other definitions for lattice that I've seen before include "Regular arrangement" , "Ornamental framework" , "Arrangement with bars" , "Grid" , "Structure with criss-cross strips" .)