The most common and most likely answer to this crossword clue is the 9 letter word OUTHOUSES
I've seen this crossword clue in The Guardian
O
U
T
H
O
U
S
E
S
Buddy explains!
The straight part
We know that "Sheds" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sheds = outhouses.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does OUTHOUSES mean?
OUTHOUSES noun- An outbuilding—typically permanent—containing a toilet or seat over a cesspit.
- Any outbuilding: any small structure located apart from a main building.