Space4’s strategy to improve the environmental performance of our homes is founded on the premise that they should be sustainable by virtue of their efficient design and construction, resulting in our ‘fabric first’ approach. An important part of this approach is our Space4 technology, which is leading the way in delivering sustainable homes.
Before and after – diagram (left) showing how the Space4 frame and panels are used as the basis for one of our new homes (right).
Space4 has supplied over 40,000 homes since it was established in 2001 and is one of the largest off-site manufacturers of timber frame housing in the UK, with a manufacturing output of one new home every hour. Although the timber frame market has grown substantially, the UK’s use of this technique lags significantly behind other parts of the world.
During 2016, we realigned Space4 production to concentrate on delivering our core range of house types. As a result, all Persimmon’s core range of house types have now been converted to Space4 timber frame design, which increases the manufacturing efficiency as well as producing other direct benefits with regard to optimising the purchase of materials. Whilst this refocusing of the Space4 production planning and workflow has meant overall output for 2016 has reduced slightly on the prior year at c. 5,500 units, these units have been manufactured at greater levels of efficiency. In 2017 we will be seeking to take forward the advantages of this approach as we look to expand production further, focusing on our core Group house types.
More widespread adoption of off-site manufacturing could provide extensive benefits for the UK, both in terms of improved environmental performance and as a means of bridging the gap between the demand and supply for new homes. The use of modern methods of construction, including off-site manufacturing, has been endorsed by the Government in its recent Housing White Paper* and has also been supported by the Farmer Review of the UK Construction Labour Model (commissioned by DCLG and Department for BEIS).
Benefits for Persimmon include consistent build quality and a more streamlined construction process. Customers benefit by owning a home built to the highest standards and which is energy efficient. Our manufacturing centre in Birmingham uses Computer Aided Design and Computer Aided Manufacture technology, with the capability of producing the panels for one new timber frame home every hour. Our investment in this technology means that we are also well placed to incorporate future changes in legislative requirements for enhanced energy efficiency, swiftly and accurately.
A further advantage of off-site manufacturing is that site assembly takes significantly less time than to build a home of traditional brick and block construction with the erection of the superstructure taking one week compared to three for the latter. This reduction in the requirement for bricklayers is beneficial given this skills shortage in the sector. Furthermore, our erection process lends itself to having dedicated teams and a number of these consist entirely of graduates from Persimmon’s Combat to Construction initiative.
Off-site manufacturing is also less susceptible to delays arising from adverse weather conditions and having the frame and roof in place quickly provides safe and dry working conditions for our tradespeople while they are completing the homes. An additional advantage is that timber frame housing uses less heavy machinery during its construction. Given this is an area that accounts for a large part of our energy consumption reduced demand for this type of equipment will be an important contributor to reducing our greenhouse gas emissions.
Persimmon timber framed houses
The direct and indirect environmental benefits of off-site manufacturing are considerable, not least of which is the use of timber rather than other, less sustainable, building materials. All of Space4’s timber is purchased from certified and sustainable forests. Moreover, factory produced closed panel insulated systems, such as those produced by Space4, enhance air tightness, thermal and acoustic performance – all of which are highly valued by our customers. They lower energy costs, and are considerably more energy efficient than the existing housing stock. In addition, our sites where off-site manufacturing is used have a lower level of waste.
A recent innovation by Space 4 is the “room in the roof” product. Used increasingly on our two and a half story properties, these panelised roofing solutions provide a fully self-supporting, pre-insulated roof, gable and party wall solution. As a result, they deliver improved speed of build and reduce significantly the man hours worked at height. Persimmon used a total of 1,082 panelised roof kits in 2016, over 400 of which were supplied by Space4.
We reported last year that an increasing number of our homes are built using concrete bricks, which are easier to make and are more environmentally friendly as they require less energy during the manufacturing process.
Persimmon's new brickworks plant at Harworth
After a detailed examination of the business case and consideration of the environmental impacts, we are investing £10 million to create our own brickworks at Harworth, Nottinghamshire. We have undertaken significant remediation work to bring this brownfield site – a former glassworks – back into productive use. The location benefits from excellent transport links and access to local raw materials and will begin production in the first quarter of 2017.
The plant will be one of the most advanced in the UK, with the potential to produce around 80 million bricks each year which is around two thirds of our current requirements. It utilises the latest machinery, which allows for high levels of automation, and will provide employment for 25 people. The output will be of a consistently high quality, available in a range of colours, and 100% recyclable. The carbon footprint of the concrete bricks it produces will be smaller than their clay equivalents which use larger amounts of fuel in the kilns where they are fired.