A building is a means to an end, not the end itself.
The key question is: will it release or inhibit organisational opportunities that impact on the business drivers? Those opportunities are the reason for building, but you should also look at alternative ways of achieving them besides building. If the business case for the building is sound it should reflect what the organisation is trying to achieve, the pressures it faces, what constitutes success and the contribution a building would make to that success.
The business case should not just be a property proposition written by a property consultant and it should certainly not be written merely to justify the need for a building. It should be broad enough to examine the difference between having a building and not having it, and the social and economic impacts of the building on its users.
When considering the contribution a building would make to success, be aware of ‘optimism bias’. This is the term coined by the UK Treasury, based on international research in both the public and private sectors, to compensate for the tendency of project leaders to underestimate cost and time because they want to give people good news. Of all the potential areas of optimism bias, inadequate business cases are the most common.