Facilities costs are what it takes to keep premises open: rent, utilities, cleaning, waste, security, maintenance of the building itself.
For most service businesses this is the largest overhead line after people.
Almost entirely fixed
Rent does not fall in a quiet month. Neither does most of what sits alongside it.
That makes facilities the single biggest driver of break-even, and the reason two businesses with the same revenue can have very different tolerance for a bad quarter — see fixed and variable costs.
The question worth asking annually
Not "can we reduce it" but "do we need this much of it".
Premises are usually taken at a moment of optimism and rarely revisited. A trade business that moved to scheduling from vans, or one that lost a service line, often carries space it no longer uses — and space is the hardest cost to reduce quickly, because it is contractual.
What is genuinely reducible
Utilities, through metering and equipment rather than through asking people to be careful.
Cleaning and waste, through frequency matched to actual use.
Sublet or shared space, where the lease allows it.
The renewal itself. Lease renewals are negotiable far more often than tenants assume, and the moment to raise it is months before the deadline rather than at it.
Where it sits
Under office and administrative in your accounts, and firmly in overhead rather than cost of goods sold — the rent is paid whether or not a job happens.