Schedule of Condition
If you are taking on an FRI (full repairing and insuring) lease, you have a responsibility to put the building into full repair in the first place, and give it back in repair, regardless of the state it was in when you took it. To know what you are taking on, you need a Building Survey report.

If you can get the lease modified so that you hand back the building no worse than you took it, you need a record of the original condition. A Schedule of Condition is a detailed 'snapshot' of the building on a particular day.

Schedule of Dilapidations
Repairing clauses in commercial (and residential FRI) leases are enforced through Schedules of Dilapidations. This is a document prepared by the landlord, or his surveyor, describing the current condition of the building and setting out the work he considers necessary to bring it back into repair.

The tenant may dispute part or all of the schedule, particularly if the lease is subject to a Schedule of Condition, and surveyors acting for both parties will negotiate to reach an agreed scope of works.

If the lease is still running (an Interim Schedule of Dilapidations) the work will be organised by the tenant's surveyor and checked by the landlord's surveyor.

If the lease has expired (a Terminal Schedule of Dilapidations) the two surveyors will negotiate a financial settlement to allow the landlord to repair the building ready for the next tenant.