With the government’s commitment to bring all greenhouse gas emissions to net zero by 2050, it has become imperative to look at ways in which we can ensure our future homes are ‘zero carbon ready’. A critical first step is ensuring that the fabric of domestic projects is well designed, and, by paying careful attention to detailing and thermal bridging, we can eliminate some of the issues that create poorly performing homes. With a traditional steel lintel potentially creating a major thermal bridge, correct lintel specification can have a significant and positive impact on a building’s fabric efficiency.
The recently updated Part L requirements of the Building Regulations are seen as an important stepping stone to the Future Homes Standard in 2025. But there needs to be a clear emphasis on the design of a building’s envelope without the need for future retrofitting work. The interim Part L uplift to energy efficiency requirements will mean all new homes will be expected to produce 31 per cent fewer carbon emissions through a combination of fabric improvements, low carbon heating technologies and PV panels. The 31 per cent reduction is the first step but by 2025, new housing will be expected to produce 75-80 per cent fewer carbon emissions compared to current standards. This is a potentially massive change for the industry and a real game changer.
Getting the fabric right
What will this mean for new homes and how will we meet these higher standards? One key area will be addressing the thermal performance of a building envelope through a fabric-first approach to design. If we get the fabric right and we build as designed, we will go a long way to meeting our targets. It’s an approach that will enable us to meet and even exceed regulatory performance criteria, whether it is for large-scale social housing or a much smaller residential property.
While a reduction in CO2 emissions is one consideration when designing thermally-efficient housing, an improvement in thermal comfort can also have a positive impact on occupants – adding to their thermal comfort, productivity and wellbeing.
As the UK continues on its path towards more energy-efficient homes and achieving its net zero targets, preventing heat loss by addressing thermal bridges has become increasingly important, as research has shown it can account for up to 30 per cent of heat loss from buildings.
Heat loss and lintels
Traditional steel lintels can create a significant thermal bridge in homes due to the high thermal conductivity of steel and because they span over long lengths in a typical build. Therefore, taking into account the thermal performance of lintels at design and specification stage is more important than ever. A lintel with a thermal break will dramatically reduce thermal bridging through the junction, with beneficial cost and performance outcomes.
Hi-therm+ Lintels from Keystone Lintels incorporate a patented combination of glass reinforced polymer and galvanised steel to bond the internal and external walls of a building together by spanning the intervening gap. Up to five times more efficient than a standard cavity wall steel lintel, it offers greater corrosion resistance than stainless steel lintels and has the ability to support loads equal to that of a standard or heavy duty steel lintel.
The Hi-therm+ Lintel has an impressively low thermal conductivity performance which contributes towards its Psi value of 0.03-0.06 W/mK, making it the ideal low- cost and sustainable solution for specifiers aiming to achieve Building Regulations with the fabric first approach. This solution also contributes towards the achievement of the Fabric Energy Efficiency (FEE) standards required by the Code for Sustainable Homes.
With openings for doors and windows so vulnerable to heat loss through thermal bridging, paying close attention to the details and structural elements, such as lintels, can have a huge impact on the overall thermal performance of a building and ultimately bring us closer to the carbon reduction targets proposed under Building Regulations Part L and the 2025 Future Homes Standard. If a buildings fabric is designed and built as efficiently as possible in the first instance it will continue to perform as intended and save energy for years to come.
For more information please call 01283 200 150, email or visit the Keystone Lintels website.