The short answer
Yes. CleanSL8 states that most commercial cleans happen before 8am or after 7pm, with weekend cover available. The team can work around opening hours so staff and customers are not disrupted.
The exact window depends on the building, access arrangements, alarm procedure and the amount of work required. Those details should be agreed before the first visit.
How an out-of-hours clean is organised
The quote should record the arrival window, key or access-card handover, alarm instructions, areas to clean, waste route and the person to contact if access fails. For multi-tenant buildings, confirm lift and loading restrictions as well.
A consistent checklist and cleaning log make it easier for an office manager to verify the visit without being on site while the cleaners work.
When early or late cleaning is useful
Early cleaning suits offices that open at 8am or later. Evening cleaning suits teams that finish late or need the workplace reset before the next day. Weekend cover can help when a larger one-off clean needs more uninterrupted access.
If the site handles food, healthcare or other controlled environments, specify the required products, records and waste process in the scope.