Updates to NHBC Foundation Publications

Around the end of this decade the UK government will ban the sale of new petrol and diesel cars and vans, and as a result there will be a rapid increase in the number of electric vehicles (EVs) needing to be charged. The infrastructure required to support this transition is significant. In 2019 the Department for Transport launched a consultation on facilitating EV charging in new homes and buildings undergoing major refurbishment, with the intention of introducing a new Building Regulations approved document in England. In 2020 the Welsh Senedd published an electric vehicle charging strategy confirming similar intentions. In 2021 the Scottish government started consultation on EV charging infrastructure, again with the intention of including provision within the Building Standards. It is expected that similar regulations will also be brought forward in Northern Ireland.

This NHBC Foundation publication, prepared by Cutland Consulting Limited, looks at what is a fast-changing landscape. As recently as 2018 the Foundation published ‘Futurology’, which talked about every home having an electric car by 2050. In February 2019 we published ‘Watts in store?’, which started to consider the role that EVs might play in household battery energy storage. At the time of writing, the Intergovernmental Panel on Climate Change (IPCC) has moved from trying to limit global temperature rises to 1.5°C to accepting that even with significant reductions in emissions, temperatures are likely to increase beyond 1.5°C within 20 years. This reinforces the need for urgent action to implement measures which can make a rapid and practical impact on cutting emissions.This publication provides guidance on the current state of play with electric vehicles and chargepoints, and what house builders will need to provide within the curtilage of a single dwelling or where the development has off-plot or shared parking.

The report considers the safety aspects of installation and provides a comprehensive list of standards to be consulted.

It also stresses the importance of early engagement with the relevant Distribution Network Operator to ensure that there is sufficient electrical capacity to the development site. The report finishes off with a look at future technology, some of which may appear sooner than expected. We hope that this publication will prove useful in extending understanding of the challenges and opportunities for the industry in what will unquestionably be a fast-moving context.

Vehicle-to-grid schematic:

1. The national grid may at various times have excess capacity or a shortage of supply. Electricity can flow either way, depending on the grid situation.
2. At certain times the EV battery will be charged from the grid as normal, and at other times it will supply electricity back to the grid.
3. The EV battery thereby acts as an independent battery store to assist electricity suppliers, DNOs and generators in managing grid supply and demand.

View the report

The manual begins with a reminder that a good residential building design is like any other – it starts by reducing demand. In residential buildings this is as much about reducing hot water use as it is passive building design. The guide deals with the choice of temperatures, decisions about centralisation, the use of ambient loops and the architectural implications of using heat pumps.

The manual deals predominantly with the design and optimisation of heat pump systems. It also covers the full life cycle, including installation, commissioning, operation, maintenance and decommissioning. Cost is always a key project driver – perhaps more so in residential construction than many others – and guidance on relative capital, energy and maintenance costs is included to help designers keep a weather eye on their client’s investment and the homeowners’ bills.

A  series of case studies are included detailing where heat pumps have been applied to new and existing multi-unit residential projects. In time, as heat pumps grow in popularity, so will the industry’s portfolio of success stories.

Heat pumps will be a big part of our future and AM16 provides timely guidance and resource as we start down the road to an all-electric, zero carbon future.

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Four years since the publication of Mark Farmer’s Modernise or Die review, which highlighted the construction sector’s low productivity and declining and ageing workforce, we are at a critical time in the development of Modern Methods of Construction, MMC. The potential benefits of MMC are well rehearsed and compelling, but clearly have not been realised and conventional construction remains dominant in the UK.

This guide, then, explores why this may be so, cutting out the rhetoric and focussing on technical developments in an attempt to build on experience and explain why factory-built housing is not more common.

There have been notable periods of innovation in house building and by exploring these historic developments, we can identify elements of high-quality design as well as the social and economic influences that drive change. And it doesn’t shy away from interrogating past failures so as to avoid repeating mistakes that still stigmatise the concept of offsite construction.

This guide educates and informs consumers, builders, investors and insurers about MMC. It dispels the abiding image of post-war emergency housing that, despite its reputation, contained some clever engineering and durable details. We are able, today, to cherry-pick the best of the previous decades, and, in collaboration with advanced manufacturing methods, can transform the productivity and quality of house building. I hope that this guide can be an enabler to change.

View the report

L&G Modular Homes factory in Leeds

In 2019 the Committee on Climate Change published two landmark reports which highlighted the contribution of our homes to UK carbon dioxide emissions and the opportunity to decarbonise our housing stock and for all new homes built from 2025 to be off the gas grid. The government responded with its announcement of the Future Homes Standard and an aspiration not to connect new homes built from 2025 to the gas grid.

This heralds a major change. Not just for the home-building sector, which will need to rethink and redesign its products, our homes, to meet this goal. We need to retrain its workforce and supply chain to produce and install new systems. It is a major change for homeowners, who will need to adapt their behaviour and lifestyles to using new heating technologies. It is also a challenge for those who advocate these changes to help to identify satisfactory solutions that are acceptable to consumers and to attract investment in delivering them.

This short publication begins to look at what the non-gas home of 2025 might look like. It considers the alternative heating solutions available to homebuilders; our need for hot water; and requirement for new homes to be energy efficient.

As new homes are constructed with higher levels of insulation and air tightness, and are built at greater speed, the need to ensure a quality-built, energy-efficient home is paramount. Today’s potential buyers show a growing concern not just in the build quality of their new home but also in the impact that living in it will have on the environment. Hence the widespread adoption of quality management systems and the government’s proposals for a ‘Future Homes Standard’. This will hopefully help to promote quality consistency across all areas in construction and future proof new homes with low-carbon heating and high energy-efficiency standards.

Thermal imaging, also known as infrared thermography, has been used for some time to provide a non-invasive ‘window’ at various stages of construction. It can show the thermal performance of the external walls, roofs and internal services. It is a quick and relatively easy method of implementing quality checks and tests during construction and is an effective problem-solving tool after completion.

These images show the ceiling of an upper floor at an external wall corner. The even yellow colours indicate the loft insulation has been installed to a satisfactory standard and is overlapping with the wall insulation.  

The slightly lower temperatures around the wall and ceiling junction indicate the marginally higher level of heat loss expected in this location and is not a sign of a problem.

Two fundamental and related challenges for house builders are how to increase the output of new homes while at the same time ensuring that we continue to drive up standards. In this context much attention has been focused on modern methods of construction (MMC) and the contribution they can make to expanding volume and enhancing quality. In the debate about the advantages of MMC an unfavourable comparison is often made with ‘traditional construction’ – laying bricks in mortar and laboriously cutting timbers on site being characterised as dated and inferior to modular panels manufactured in a controlled factory environment.

However, this oversimplifies the argument, ignoring the extent to which new homes supposedly built in a ‘traditional’ way actually incorporate new systems and technology, very different from what would have been used in the ‘traditional’ housing of the past. The purpose of this NHBC Foundation report prepared by Studio Partington is to describe typical (non-MMC) construction used for new homes and contrast it with ‘traditional’ methods that have been used in the preceding 100 years or so. It makes clear that what lies beneath the skin of new homes is quite different from what has gone before.

Of particular note is the improved robustness of new homes and their inherent resistance to ground movement and the ingress of rainwater. Other advances include the improved efficiency in the use of materials that comes with components such as timber trussed rafters and engineered floor joists. Added to this are the enhanced comfort and lower fuel bills which flow from the higher energy performance standards of modern homes, setting them apart from previous generations of housing.

The report reminds us that all forms of construction may once have been considered to be MMC. A case in point is timber frame, which was introduced into the UK in the 1960s and currently accounts for nearly a fifth of overall output. According to NHBC statistics, about 75% of homes currently being built are using cavity masonry construction and 16% are timber framed. Based on these figures it appears that ‘traditional’ construction will continue to play a strong role, even if its components continue to evolve, reflecting advances in technology. Against this background it is important for us to have a proper understanding of what it actually is.