CONSCIOUS CONSTRUCTION

Anyone concerned about single-use plastic bags, food miles, excess packaging and flying around the globe should be thinking very seriously about construction and the built environment, particularly in relation to build waste, inefficient construction methods and travel miles relating to materials and the workforce. Research is starting to reveal what impact construction has on the environment, including a building performance over its life cycle. A recent study* found new houses emit five times too much carbon. There are many reasons for this, including the disproportionately large houses built in New Zealand, which in turn also require more materials to build them and more energy to run.

Where we build is as important as how we build, and this also needs to be factored into the environmental credentials of the construction sector. Industry and clients need to include in their build-credentials factors that lessen inefficient delivery of materials, build waste and the movement of the workforce so they are impacting less on the actual environment.

Too often we see delivery trucks making multiple trips to the build site with a small stack of wall lining or a builder’s van with a couple of 4x2s tied to the roof rack. The build site, to which those materials are being inefficiently delivered, will always have a skip bin or trailer filled – multiple times – with offcuts that could have otherwise been used. Materials could have been managed better or damage to them avoided in the first place if they were in a controlled offsite factory setting. I’ve personally visited offsite factories where all offcuts from framing, wall linings and insulation are sorted, stored and used on the next house.

“Too often we see delivery trucks making multiple trips to the build site with a small stack of wall lining or a builder’s van with a couple of 4x2s tied to the roof rack. The build site, to which those materials are being inefficiently delivered, will always have a skip bin or trailer filled – multiple times – with offcuts that could have otherwise been used. Materials could have been managed better or damage to them avoided in the first place if they were in a controlled offsite factory setting.” Scott Fisher, CEO, PrefabNZ.

There’s not a lot of research to be found, and we could do with more, on what carbon footprint the construction workforce has on the environment, particularly with regard to movement from site to site. But offsite factory settings eliminate a lot of that. They provide the benefit of less travel disruption, and the majority of the workforce travel to the offsite factory, not to various sites across a city; there’s a carbon saving already.

Within the construction industry, the offsite manufacturing sector is dealing with these inefficiencies head on, and delivering quality, high performing houses in a shorter time frame. I am confident that the purchasing public who are conscious of the carbon footprint of their home will start to focus on where their home is built as much as how it is built; both are equally important. It is the conscious consumer who will be a driving force in the growth of the offsite sector.

On another acutely topical note, Covid-19 has certainly changed the world in a very short space of time and I trust readers are navigating the challenges facing the industry. The OSM sector’s role in the economic rebuild and to the broader construction sector is critical and as the peak body for the sector we are getting this message across to the government, policymakers and officials. OSM is now part of the mainstream conversation and the key benefits remain valid in a post Covid-19 world, if not more so.

The economic rebuild will be driven by sectors that demonstrate improved productivity and innovation, and that contribute to global issues such as sustainability. Traditional construction companies, developers and clients are increasingly looking at ways to do things better, quicker and at a higher quality and OSM allows them to do this. Post Covid-19 will see our sector continue to thrive. ■

*A science-based approach to setting climate targets for buildings: The case of a New Zealand detached house. https://doi.org/10.1016/jbuildenv.2019.106560