The secret of good design

I was reading through BSj (Letters, 03/04) and came across a letter on why the practice of transferring design risk to contractors is not the way to get the best design.

It expertly explained why a contractor-led design team is unable to develop appropriate designs and address key issues of sustainability, energy conservation and whole life value when appointed in a lowest cost situation. I was following this train of thought as the case was being built, and I was ready for the conclusion that lowest cost tendering doesn't work in the design/build environment. But the unexpected conclusion was that a fully predesigned project, with contractors subsequently appointed by competitive tender, is the answer.

Having experienced this loop before, I though I'd better join the debate. I believe I understand the thinking; indeed, I used to think the same way. When I was in PSA, we used lowest cost tendering. The main issue was the amount of change we saw on site. We were always fighting the battles of variations and claims. We tried to write conceptual performance specifications that passed design risk over to the contractor, so they were free to make their own design decisions, thus minimising changes. But that hadn't worked due to insufficient design fees, inadequate information and short term thinking.

A key problem is that design is done in isolation. You need people with experience to share their knowledge.

The next step was to pull more design up front. 'If we fully predesign before we appoint there won't be any changes to argue about,' went the logic. There is something intuitive about this which makes you feel you have it! Unfortunately, sometimes the right answer is counterintuitive. The real problem is that design is done in isolation. In order to provide a fully designed project, concepts must be followed up with decisions about selection and assembly. This requires access to people who have lived with the consequences of these selections in the past, to draw on their experience. This experience is rarely available inside design houses and if it is, it quickly goes out of date. Even if it were possible to somehow identify all the best methods, processes, systems, materials and components and then to clearly encapsulate them within drawings, specifications and documents the most important issue remains: ownership.

The difficulty, and the beauty, of design is there are no right answers. Good design is the selection of the most appropriate solution to a complex interaction of problems, all with differing priorities and consequences. Those responsible for conceptual design often have a contradictory impression of the best solution to those responsible for implementation. In construction these two parts of the industry have been separated and, irrespective of which part takes on the design responsibility, the other will frequently have a different opinion on the best/right decisions. Of course this gets clouded further by the fact that the clients (funders), end users, operators and maintainers also have their own perspectives. There is design in every element of the product right down to the selection of appropriate raw materials.