Open-market rent review is one of the most common mechanisms in UK commercial leases. The exercise is to determine the rent that the premises would command on the hypothetical letting described by the lease at the review date.
The lease defines the market
The review clause normally specifies the hypothetical term, assumptions and disregards. The actual occupation is therefore not always identical to the hypothetical valuation exercise.
Evidence
Relevant lettings, renewals and rent review settlements are analysed for timing, size, location, specification, incentives and lease terms.
Upward-only provisions
Many leases provide that the reviewed rent cannot fall below the rent already payable. The exact wording should be checked.