Paul Beech from Armatherm discusses the role thermal bridging plays in limiting building performance, and why ‘smart’ building design is the means to address it and achieve genuine energy efficiency in residential buildings.

Smart buildings will play a vital role in the journey to net zero; however despite having energy-efficient solutions like solar panels and improved insulation specified into designs, buildings can still underperform, primarily because of an overlooked issue – thermal bridging. When any building is constructed, structural connections interrupt insulation layers, creating opportunities for heat to easily transfer from interior to exterior and vice versa. As a result, internal temperatures can fluctuate, increasing the energy required to maintain comfortable indoor conditions.

Looking closer at the general definition of a ‘smart building,’ these are structures that use technology to optimise resource usage, efficiency and comfort for occupants. They tend to be equipped with a variety of modern and innovative technologies, from artificial intelligence, augmented reality, and the Internet of Things. Smart buildings are designed to monitor building performance on a variety of metrics, such as comfort, efficiency and productivity. To achieve this, they’re equipped with digital sensors that can gather data and connect with software to provide opportunities for optimisation.

This is a great development in the world of construction to ensure energy is being used as efficiently as possible, with sensors monitoring temperatures, air quality and lighting to see where energy is required. Examples of smart buildings can be seen across the globe, including The Edge in Amsterdam, Capital Tower Singapore and, closer to home, Tottenham Hotspur Stadium in the UK, where solutions have been incorporated as part of the stadium’s wider intelligent building infrastructure.

With the rise of these innovative buildings, energy efficiency targets appear closer than ever to being achieved. However, even the most intelligent systems cannot compensate for thermal bridging within the building envelope.

Thermal bridging occurs when a more conductive material passes through or interrupts the insulation layer within a building envelope, allowing heat to transfer more easily between internal and external environments. This often occurs at structural junctions such as balconies, parapets, canopies, slab edges and steel connections where materials like concrete and steel bypass insulation layers.

As modern buildings become more thermally efficient and airtight, the impact of these weaker points becomes more significant. Even relatively small areas of thermal bridging can cause detrimental effects; in residential developments particularly, thermal bridging can have consequences beyond energy performance alone. Surface temperature reductions around poorly insulated junctions can increase the likelihood of condensation forming, contributing to mould growth and long term moisture issues. This can negatively impact indoor air quality, occupant wellbeing and building durability, while also increasing future maintenance requirements.

For housebuilders and developers focused on achieving net zero targets, this presents an increasing challenge. Improving building efficiency is no longer solely about specifying more insulation or incorporating renewable technologies, there is increasing recognition that the continuity of the insulation layer is equally important.

Addressing thermal bridging effectively requires consideration at the earliest stages of the design process. Once structural connections and junction details have been established, opportunities to improve thermal continuity can become more limited and potentially more costly to resolve in retrofit projects.

A fabric-first approach is increasingly viewed as one of the most effective strategies for improving long-term building performance which prioritises the thermal qualities of the building envelope itself, rather than relying solely on mechanical systems or renewable technologies to offset inefficiencies. This includes improving airtightness, insulation continuity and junction detailing to minimise uncontrolled heat transfer.

However, thermal performance should not be considered in isolation. Structural requirements, compressive strength, fire ratings and long-term durability must also be considered when selecting materials for structural junctions. It’s also important to note that different applications may require different solutions depending on loading conditions, environmental exposure and overall building design.

A building may achieve strong theoretical calculations, but if thermal bridging is not adequately addressed during specification and construction, operational outcomes may fall short of expectations. As regulations surrounding operational energy use continue to evolve, the gap between designed and actual building efficiency is also receiving increased scrutiny. 

This is particularly relevant as developers seek compliance with updated Building Regulations and sustainability frameworks designed to reduce carbon emissions across the built environment.
In most cases, improving junction detailing and reducing thermal bridging can contribute to lower energy consumption without requiring major design changes elsewhere in the project.

The issue is becoming increasingly important in smart building design with intelligent building systems intending to optimise energy use through responsive controls, occupancy monitoring and automated environmental management. However, these systems can only operate effectively if the building fabric itself performs efficiently. Where uncontrolled heat loss persists, heating and cooling systems may work harder to maintain stable internal conditions, reducing the effectiveness of otherwise advanced technologies.

For developers balancing sustainability targets with long term operational costs, this highlights the importance of viewing building performance holistically. Smart technologies, renewable systems and insulation strategies should not be considered independently from structural detailing and thermal continuity.

Across the industry, there is growing awareness that achieving net zero will require greater collaboration between architects, engineers, developers and manufacturers from the earliest design stages. Companies which specialise in structural thermal break solutions are increasingly involved earlier in the design process, as project teams place greater emphasis on improving thermal continuity and long term operational performance.

Paul Beech is general manager at Armatherm