Clue 1: house staff refurbished toilet facilities (3,5,7)

I believe the answer is:

the usual offices

'toilet facilities' is the definition.
(informal term for toilets)

'clue 1 house staff refurbished' is the wordplay.
'1' becomes 'I' (roman numeral).
'refurbished' indicates an anagram.
'clue'+'i'+'house'+'staff'='clueihousestaff'
'clueihousestaff' is an anagram of 'THE USUAL OFFICES'.

I've seen this clue in The Guardian.

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