The Insulation Manufacturers Association (IMA) explains how architects can employ high performance PIR insulation as the key to design homes that are not only low carbon and climate resilient, but which are of high quality.
The UK housing stock accounts for 15% of the UK’s greenhouse gas emissions due largely to heating with oil and gas. Specifying thermally insulated building envelopes can play a crucial role in reducing this impact across the evolving housing delivery landscape which includes community-led schemes, housing associations, self-build, and joint ventures.
In each case, employing design expertise can enhance the delivery and long-term performance of new homes. By embracing ‘fabric first’ principles, a well insulated building envelope achieves high performance, low maintenance and reduced energy consumption and could help protect households from future energy price volatility.
Understanding U-values
Reducing heat loss starts with achieving lower U-values throughout the building envelope. Lower U-values in walls, floors and roofs reduce heat loss, resulting in enhanced thermal performance, which in turn will help to deliver the standards required. PIR and PUR insulation products are incredibly versatile as well as effective, and are available in a range of forms including boards and blocks, cavity injected, composite panels as well as a spray and panel insulation.
With the ability to achieve lambda values as low as 0.021 W/mK, PIR can achieve the required insulation performance with less thickness than other commonly used insulation materials. Its exceptional insulating properties, as well as high strength and light weight mean it is used widely across residential, commercial and refurbishment projects.
Design-led specification
Good house design is essential to ensure that insulation strategies are fully realised in practice. Early-stage specification decisions, including material selection, coordination with structural and MEP (mechanical, electrical and plumbing) elements, and careful detailing, directly influence the thermal performance of the building. Integration with airtightness strategies and thermal bridge mitigation is also essential to achieving the intended U-values and overall energy efficiency.
Detailing & performance
Maximising the benefits of insulation in buildings requires accuracy in detailing. For example, ensuring junctions are appropriately designed and constructed will make a significant contribution to reducing heat loss. Responsible for up to 30% of a dwelling’s heat loss, thermal bridges occur at breaks in insulation at junctions and openings, causing heat loss which can affect internal temperature and an increased demand for heating. Success hinges on rigorous quality control throughout both design and construction with good detailing necessary at every junction and interface.
With little or no maintenance needed for the insulation once installed, energy efficiency is built into the building fabric for the life of the building. By reducing the total energy consumption of a building, the size and capacity of any renewables can be reduced, which could reduce capital and running costs.
Health, wellbeing & social impact
Well insulated buildings can also yield significant benefits for users and occupants as high thermal performance provides excellent internal conditions during both the winter and summer months.
Other social benefits associated with better insulation are the reduction and potential elimination of fuel poverty, as a greater proportion of heat is retained more effectively in homes with superior fabric. The provision of an enhanced envelope results in a reduced overall fuel demand, for more comfortable living conditions over winter months, compared with buildings with poorer thermal performance.
Future-proofing homes
The best opportunity to meet the UK’s housebuilding targets without sacrificing quality and to future proof our homes, starts with energy efficient fabric – but must also include wider strategies for ventilation, airtightness and the inclusion of renewable technologies such as solar PV and heat pumps. Specifying such a combination of solutions can play a huge part in ensuring that new housing is compliant today, but also resilient and adaptable to the climate challenges of tomorrow.
Article provided by the Insulation Manufacturers Association (IMA)