Sustainability Series: Week 4, Housing and masonry

Webinar: Detailing thermal performance

Recorded: 04 October 2023

This webinar provided essential guidance for the understanding, assessment and detailing of thermal junctions in the construction of masonry homes to meet current Part L requirements and in preparation for The Future Homes Standard.

A recording of this event is now available in the on-demand library.

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Blog: Both sides of the climate change coin 

To ensure the sustainability and long-term suitability of new housing, it is essential that when considering their design and material selection, both climate change mitigation and resilience to climate change impacts are considered. This blog highlights some of the existing and evolving resources available to help. 

Operational excellence and meeting regulations 

A crucial aspect of climate change mitigation is of course optimising the operational efficiency of new housing. Strategies for providing high fabric efficiency are well established through consideration of insulation, airtightness and reducing thermal bridges. There are many examples of new properties constructed using concrete and masonry that meet or exceed current building regulations energy efficiency requirements. The Concrete Centre and colleagues in MPA Masonry have been providing guidance for detailing, and sharing best practice for many years.   

Current resources, provided on this page, include an updated publication providing U-values and wall thicknesses for a range of concrete and masonry construction options, case studies and a selection of on-demand CPD webinars including PassivHaus examplars. Also, a recent publication on Part L, supported by the masonry industry, is available from The Future Homes Hub: Part L 2021: A guide for housebuilders and their advisors, Masonry Construction’.

A new Concrete Compass for housing helps to navigate to the variety of resources available, including new guidance to keep pace with evolving regulation for energy efficiency and rising aspiration of clients to reduce energy consumption.

Attention to detail 

Essential new resources are also provided in the form of ‘Recognised construction details’, a free online tool that provides a large selection of coordinated construction details for housing using masonry and concrete, each with verified thermal performance (PSI) values for use in SAP.  A focus on the thermal performance of detailing for housing is the focus of our webinar event of this week (now recorded and available here) including a presentation by Studio Partington, key partners in the development of the details. 

Embodied carbon reduction and whole life carbon considerations 

Currently a lot of attention is being paid to embodied carbon, and this is an important part of measuring whole life carbon. Whole life carbon is the best means of establishing the full carbon impact of any housing development. While Life Cycle Analysis (LCA) has been established for years as part of the Code for Sustainable Homes, its successor the Home Quality Mark and BREEAM, new skills and better data are required to achieve an accurate assessment and comparison. The Concrete Centre invested in that exercise and published a study comparing the Life cycle carbon analysis of a six-storey residential building. The Future Homes Hub are developing a simple tool to assist house builders engage in the process of measurement and material selection, specific to housing development in the UK, which should include options to take advantage of the growing number of lower carbon concrete and masonry options available. Project 80, a recent housing development by Midland Heart in Birmingham demonstrates that significant whole life carbon savings were achieved using concrete and masonry. This solution provides benefits beyond carbon such as an established local supply chain and reliable, proven performance.  

The latest MPA Precast and MPA Masonry Performance Report shows good progress has been made in reducing the embodied carbon of UK manufacturing through the use of renewable energy and lower carbon materials and a recent survey of masonry manufacturers indicates that further development of new lower carbon products is well underway across the sector.  

Whole life carbon emissions encompass not only manufacture and construction but also carbon associated with replacement, and maintenance of materials and end-of-life stages. And in this respect the long-term durability of concrete and masonry, and their ability for reuse and recycling helps contribute to lower emissions over a building's lifecycle. 

Climate change adaptation and resilience 

Climate adaptation is also an essential consideration if our new homes are to remain comfortable and safe in the long term, not to mention resilient to increased maintenance and repair in the face of changing environmental conditions. 

As the UK experiences rising temperatures, addressing the risk of overheating in new homes is crucial, and is now a requirement of the building regulations. The use of thermally-massive materials, together with shading and night-time cooling, is a long-established strategy for passive cooling in warmer climates. Further guidance can be found here. The Concrete Centre also recently supported the publication of the FHH’s guide on meeting Part O.  

The resilience to flooding of new homes is not yet, however, fully embedded in building regulation, but rather managed by the planning system. In 2021 5% of new homes were built in areas of high flood risk or risk of surface water flooding, and areas impacted by flooding are predicted to increase. The lack of resources in planning authorities to effectively undertake compliance checks is well documented, and this, combined with a general lack of clarity on flood risk and flood resilience measures across the board, means that new uninsurable homes are being constructed.  The Code of Practice for property flood resilience, published by CIRIA provides some guidance, but the planned revision to BS 85500, Flood resilient construction, due to be published in 2024, will build on current guidance for appropriate material selection and detailing with a focus on new homes. Contemporary concrete and masonry structures are inherently robust with little or no susceptibility to water damage, offering good long term solutions requiring limited resource input as a result of water peril. 

Considering fire safety in construction is of course an essential minimum requirement in the building regulations for all buildings, but the recent spate of summer wild fires has highlighted the benefits of resilience to fire in all homes, and not just high-rise buildings. 

In conclusion, homes constructed using concrete and masonry materials can play a crucial role in addressing climate change. They can provide both operational energy efficiency, and embodied carbon reduction, simultaneously enabling homes to adapt to the challenges of a changing climate, such as overheating, flooding and fire. 

Written by Elaine Toogood, Director, Architecture and Sustainable Design, The Concrete Centre