Building confidence in offsite construction


A new Memorandum of Understanding has been signed by warranty providers to develop a set of standards for assessing homes built using Modern Methods of Construction. NHBC innovation manager Richard Lankshear discusses the MoU, the growth of offsite systems and a new service, NHBC Accepts

In August, a Memorandum of Understanding (MoU), was signed by warranty providers including NHBC, BLP Insurance and MDIS to develop a common set of standards to assess homes built using Modern Methods of Construction.

The initiative is designed to make it easier to secure a warranty on these properties to increase both industry and consumer confidence in housing built using offsite and other innovative systems.

Housing minister Christopher Pincher backed the MoU, saying it would support new technologies that “could see us leading the world in the design of high quality, low carbon homes with the mortgage and industry products needed to support them.”

The agreement was also welcomed as an “important milestone” by Mark Farmer, chair of the MMC Working Group and the government’s MMC champion.


“Greater collaboration and transparency in technical assessment and validation across the market will ensure we have consistency of approach and can drive a more unified quality and standards-led approach to innovation,” he said.

Building confidence in MMC

Richard Lankshear, innovation manager at NHBC, said the Memorandum of Understanding represents a drive towards greater transparency so those who are working in MMC can understand how decisions are made.

“NHBC Accepts goes a long way to deliver that and we were pleased to have Mark Farmer recognise this,” he added.

“It helps no one for different warranty bodies to have a different set of technical standards and, particularly in the world of offsite manufacture and MMC, it is imperative that these standards can be shown to address potential concerns. Our standards have been developed over 80-plus years and based on extensive data from the UK and abroad, and have helped to drive the continued improvement in the construction quality of new homes.

“We are wholly committed to building confidence in MMC and believe that it has an important role in helping the industry and government to deliver safe, sustainable places to live over the long-term. The MoU will help us all to achieve this and hopefully lead to a more collaborative approach.”

Offsite systems have seen significant growth in the last few years as the UK looks to address housing supply issues and improve the efficiency and sustainability of new homes.

“A couple of years ago, we saw a real uptick in MMC systems, which led us to set up a team looking specifically at innovative forms of construction. Although there have been levels of interest in the past, we saw this as different to previous times with the strength of government support, housing developers investing in their own facilities, as well as growing interest from housebuilders,” said Lankshear.

“Since then, I would say MMC is on a steady upward path, though the numbers are still small. There has been growing demand for and an increase in the use of MMC. Last year, we saw 1% to 1.5% of schemes being registered as MMC; now it’s over 5% – one in 20 homes are registered with using a form of MMC.

“What is interesting is the mix of different systems – some are volumetric but there are many panelised systems, as well as site-based and other components. So I’d say the clear lesson is that one size does not fit all – different systems will be suitable for different buildings, location, topography, sizes, ground conditions etc. For us, though, it is simple as our only measure is one of quality – does this meet NHBC Standards?”

NHBC Accepts

To support build quality and confidence in new homes constructed using offsite methods and other MMC systems, NHBC has launched a new service, NHBC Accepts, which offers a fast track to obtaining a warranty.

“We ask manufacturers to demonstrate that their MMC system meets NHBC Standards through a detailed review of the design, method of manufacture, quality controls and onsite construction. And we are transparent in our requirements so that all those who live in, lend to and build with MMC systems can be confident in the quality of their homes,” says Lankshear.

“The MHCLG definition framework for MMC highlights the broad nature of the products and systems that we review, from fully fitted volumetric units to panelised systems to site-based products and building components. However, the principle question remains the same: how can you demonstrate that your product meets our technical requirements and can do so over and over again?

“But while the question remains the same, it has meant that we need to be able to interrogate systems built from all common structural materials (and some less common), above and below the ground and manufactured both in the UK and abroad. To do so, I have a team with a broad background (architects, engineers, surveyors and inspectors) and the great strength of NHBC means that we can also draw on the specialisms of others where required.”

Since its launch in July, NHBC Accepts has received over 120 new enquiries, as well as messages of support from developers, lenders, property lawyers, agents and consultants. The first new systems have been welcomed on board, with more to follow in the coming months.

Andy Mason, head of residential at Lloyds Banking, said: “We see Modern Methods of Construction properties as a positive development which will help with the supply of quality new homes. NHBC Accepts accreditation service gives us confidence that quality standards are delivered consistently for homeowners.”

Richard Petty, head of UK living at JLL, added: “One of the big challenges for surveyors in this market in recent years has been the plethora of manufacturers and technologies, the competing claims for these and the need for greater consistency in evaluating what is being delivered. In our view, NHBC is already seen as the ‘gold standard’ for warranties on traditionally built homes.

“The introduction of NHBC Accepts accreditation is a hugely important step for us in our due diligence and will be vitally important in putting MMC homes on a level playing field with traditionally built homes by helping our due diligence when assessing and valuing these new technologies. We welcome the initiative and look forward to seeing its widespread adoption.

NHBC Accepts is intended to build confidence in innovative construction through robust review, with technical documents and details of continued inspections of accredited systems published to ensure transparency for homeowners, lenders, developers and investors.

But, says Lankshear, in reviewing systems, there are three common areas where confidence is essential that are overlooked.

“First, that design should follow established principles. We know how to design timber, steel, concrete buildings – what works and what goes wrong. So just because a home is manufactured offsite, doesn’t mean we should ignore the lessons of the past,” he explains.

“The second area is in manufacturing production controls. To achieve quality, we often see people underestimate the level of detail required for manufacturing production controls, and there needs to be significant time and investment in the design for manufacture and assembly.

“And finally, the interfaces on site need to be addressed. We require a clear installation manual for each accepted system that sets out the method of transportation and erection, detailing all interfaces and ensuring that tolerances and quality checks are clearly set out.”

Technical reviews

NHBC Accepts requires all manufacturers to provide a system manual: a comprehensive document that sets out the scope of the system, the construction details and specification, and, importantly, the evidence of performance.

It also requires a fully audited and certified quality management system to be in place and, after acceptance, NHBC continues to carry out checks, both in the factory and on-site, sharing knowledge with manufacturers to help them continually improve.

Mark Farmer, chief executive of Cast Consultancy and author of the Farmer Review, said: “I welcome the launch of NHBC Accepts. It’s a step forward that sees the UK market leader in warranty and insurance for new homes making its commitment to high-quality Modern Methods of Construction clear.”



Richard Lankshear
Richard Lankshear

Richard Lankshear

Innovation manager


+44 (0)344 633 1000

Twitter: NHBC

LinkedIn: NHBC


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