Otago Polytechnic

Prefabrication has potential to help answer New Zealand's need for more houses.

New Zealand has a shortage of housing and it has been suggested that we could address the building skill shortage by using prefabrication more. While doors and windows and roof trusses are already prefabricated, the process of construction could be streamlined by also prefabricating entire bathroom units and kitchen units for example. Prefabrication also had advantages in reducing waste of time and materials.

Don Samarasinghe is a Senior Lecturer in Construction at our Auckland International Campus. Don has been investigating whether in fact prefabrication is the answer. Under his supervision two students interviewed twelve builders, architects and manufacturers and suppliers of prefabricated products. Don has identified several barriers to the increased uptake of prefabrication. Specialised tools and equipment, and training for staff are required for builders to install prefabricated components. There is uncertainty over whether the volumes of work in New Zealand would justify this investment. There is a reluctance amongst builders to change from what they is familiar and known to work.

One part of the solution is more training, not just for builders but also for building inspectors. Design and build collaborations can also help to increase confidence and opportunities to work with prefabrication. New government policies promoting the use of prefabrication in affordable housing would be helpful and Prefab NZ can also contribute by creating and sharing resources for builders, not just for designers.

NATURAL & BUILT ENVIRONMENTS

November 2020