Adrian Doyle from McMullen Facades, formerly part of the Lakesmere Group, takes a closer look at how the development of offsite manufacturing techniques is reaching new heights in the high-rise residential market.
The many benefits that offsite construction can offer have long been recognised and yet its role in the housing market continues to be much debated. With the industry now facing challenges from the uncertainty of a post-Brexit Britain to the very real issues of the housing crisis and construction skills shortage, offsite construction is once again back in the spotlight following the publication of the influential Farmer Review, the draft London Housing Strategy and the recent report by the London Assembly.
Offsite – at home in the residential sector?
The high-rise residential market is a prime example of the advantages that can be gained by putting the theories of offsite manufacturing and construction into practice. The need to meet the demands of the rental sector through quicker construction as well as the desire to improve quality, safety, control costs and meet strict environmental targets have all helped to highlight the important part that offsite construction has to play in this challenging sector. Consequently, in terms of our own order book, we have seen a significant increase in demand for our offsite manufacturing expertise to deliver unitised glazed facade solutions to high-rise residential projects up to and above 40 storeys.
Safety, speed and site challenges
One of the greatest challenges of delivering high-rise residential projects, and one of the key drivers behind the development of our own offsite offering, is ensuring a safe working environment. By manufacturing and assembling unitised facade systems at our dedicated in-house facility here in the UK, we are able to significantly reduce work on site and, more importantly, the amount of time working at height.
This was the case at the Elephant Road development in London’s Elephant and Castle area, where we were appointed to deliver the vertical facade to the scheme’s 23-storey tower. Located in a densely populated urban area, the logistical problems of limited access and storage space on site were successfully overcome through the use of offsite construction techniques. Through the offsite manufacture of the unitised facade panels, significant time savings were also brought to the project with the team delivering on average one floor per week.
An additional challenge throughout the constraints of this project was inclement weather and high winds, particularly in terms of the delivery of the balconies. Again the use of offsite manufacturing and ‘just-in-time’ deliveries enabled any time lost during the installation process to be quickly recovered.
Quality control
Offsite manufacturing doesn’t only give greater control over the speed of construction and work completed on site, it also offers important advantages in terms of ensuring the quality and performance of the facade system. This level of technical expertise in offsite manufacturing is vitally important in order to give architects and developers the design flexibility they desire. A case in point is the Pinnacle, the flagship 15-storey residential tower at the heart of London’s Battersea Reach development which boasts a striking facade that is completely curved with no flat elevations. By designing and manufacturing the unitised panels in factory-controlled conditions before being delivered to site, improved accuracy at the setting out stage ensured the correct building tolerances were successfully achieved.
Developing designs
The belief that the specification of offsite-manufactured elements requires a compromise in terms of design flexibility is undoubtedly one of the main reasons the industry as a whole has been so reluctant to embrace it. Supply chain collaboration has been key to changing this view and as more and more clients working in the high-rise residential sector recognise the benefits of early engagement with product manufacturers and specialist contractors, there is greater scope to create cost-effective and bespoke offsite solutions that don’t compromise on design intent.
At the Hoola development in London, where McMullen was appointed to deliver the unitised facade system to the two 23- and 24-storey towers, the team worked closely with Carillion and the developer HUB Residential at pre-tender stage to develop a bespoke facade system design that provided a fast-track installation solution and enabled follow-on trades to commence their packages much earlier than usual. As well as bringing practical benefits, the striking facade package also gives the development a unique sense of identity, with the bespoke pre-fabricated curtain walling and feature curved glazed balustrading designed to give a rippled ‘wave’ effect that reflects the development’s waterside location near the River Thames.
Uniting the industry on and off site
The environmental benefits of offsite in terms of reducing waste and carbon emissions is widely known but it’s important to remember that much of this is diluted if products have to be delivered from overseas. The ongoing support of UK-based manufacturers like McMullen through early engagement and the proactive, rather than reactive, specification of offsite elements is therefore vital to ensuring the continuous development of the sector. New career opportunities are also being created through the establishment and expansion of factories and manufacturing facilities which, unusually for the construction industry, offer a permanent place of work.
As a move away from traditional building methods, offsite can bring tremendous benefits but it also requires significant change, not only in terms of how projects are designed and products specified but, more importantly, how they are financed. Such a sea-change has been the sticking point for many but behind the rhetoric and debate, in manufacturing facilities and on construction sites across the UK, important progress in product innovation and project delivery has already been made. The foundations for an offsite revolution have been laid so now, let’s get building.
Original link - FCA Magazine
