Living in a Material World
Players
The answer is not simple because there are so many players involved in the building process.
In a traditional building contract, the prospective owner of the building determines the needs of the future occupier, goes to the bank to borrow money, and engages an architect. The architect creates a design to meet the owner's needs, in consultation with the structural engineer and other experts. The completed drawings are used by the quantity surveyor who makes a cost estimate and advises on possible savings.
The drawings, specifications and schedule of quantities are put out to open tender, and the successful building contractor is awarded a contract for construction. The local council is involved in issuing a building consent and monitoring construction. The project is built with the assistance of the project manager. Non-structural uses in fittings and furnishings will be specified by the architect or interior designer.
All of the players in this system may be involved in selecting structural and finishing materials, at different stages of the project.
There are many variations on the traditional approach described above. For example, the contractor may be the owner acting as a developer, with no occupier in mind; or the contractor may engage the architect and structural engineer to design different parts at different times. For industrial buildings or bridges there may be no architect involved. Sometimes the project manager is appointed first, and engages the consultants and the contractor, managing the entire project on behalf of the owner. In some of the new contractual arrangements all parties work together and share both the risks and the potential profits of the project.
Material selection decisions will be made at different times by different players, often in consultation, and based on many factors:
- cost of construction
- availability of materials
- promotion by materials suppliers
- knowledge and preferences of the owner or designer
- what has worked in the past
- ease of construction
- performance in daily conditions (appearance, colour, thermal performance, durability and weathertightness, acoustic performance, deflections and vibrations)
- performance in extreme conditions (earthquakes, extreme weather events, fire)
- expected cost of maintenance
- fashion trends
- environmental factors and sustainability
Different aspects will have more significance at different times. For example, some players may be reluctant to use timber following recent problems relating to weathertightness and wood quality. Education and promotion are needed if future decisions are to be based on science rather than on perception.
The construction industry is a major New Zealand industry with strong traditions, healthy competition and well-established procedures. Changes occur slowly unless there are strong incentives. Most buildings are constructed with borrowed money; so lending institutions and the insurance industry also have to be comfortable before significant changes occur.
Structural engineers are key players, because regardless of what the owner or builder or architect wants, a building consent will not be granted unless the structural engineer can demonstrate that the structure and structural materials meet the requirements of the New Zealand Building Code. Consulting structural engineers work in a very competitive business environment, so they cannot explore new ideas unless commissioned to do so by their clients.
The owners are key players because they pay the bills, and can instruct other players. Owners or investors without a special commitment to timber have no incentive to build in it unless there are demonstrated benefits, especially in cost, appearance and functionality. Benefits can be demonstrated through education and positive case studies. Any change in building materials or methods will only become viable or popular if a significant number of successful applications in the marketplace give others confidence to follow the leaders.
The timber industry can provide such leadership. It is no surprise that several very large timber buildings have been built by timber industry players for their own storage, processing or office facilities; as owners, they can make these decisions at the very start of the design process. There is nothing to stop the industry from constructing more timber buildings, to act as case studies and examples for the construction industry to follow. The owners could also save money by providing some of their own materials at cost.
