The recent upturn in the new-build housing sector has led to increased interest in construction techniques and a particularly renewed interest in offsite work.
Enhanced awareness in offsite methods was predictable. History tells us that recessions are generally followed by a skills and materials shortage and a desperate search for ways to increase capacity quickly.
Factory production and prefabrication methods are not new answers – they have been around in various guises since the post-war housing reconstruction programme but have suffered from the ‘boom and bust’ economic cycles.
Factory prefabrication works fine if a financially viable and consistent volume or throughput can be maintained. Only then do the costs start to compete with those of traditional construction.
“Factory prefabrication works fine if a financially viable and consistent volume or throughput can be maintained”
This current upturn has perhaps been unique because of the added stimulus of climate change, and the realisation that long periods of rain and wind make bricks and mortar an uncertain way to build.
So, new factories are being established, new concepts are being invented and value-engineering experts are back on the case, with new systems and materials that are being used and re-engineered in novel ways.
We are now in an era where ‘passive house’ standards are common across Europe – not least because of the level of quality control that can be implemented in a factory compared with a construction site.
The BuildOffSite Property Assurance Scheme was established to provide lenders and valuers with access to a database that would allow them to check whether a specific property has been built using a BOPAS-assessed method of construction.
This gives them assurance that the form of construction should suffer no disproportionate maintenance for a minimum period of 60 years.
“Concerns remain as to the long-term durability of homes built from offsite construction techniques”
The ‘assurance’ is based on the building system’s design and manufacture, having been subject to a Lloyd’s Register competency and process assessment and reviewed for its durability and associated maintenance requirement.
Naturally, concerns remain as to the long-term durability of homes built from offsite construction techniques. This has been highlighted by recent reports in the press, relating to the Design for Manufacture scheme at Oxley Woods, where numerous defects have occurred in the construction.
Had the system adopted here been subject to a BOPAS review and the site-specific warranty checks employed by BLP Insurance, the defects that have occurred might have been avoided.
Innovation in our industry is back with a vengeance and with it new materials and new mixtures of materials along with novel engineering are laying down the foundations for a new era of construction.
Jeff Maxted is director of technical consultancy at BLP Insurance