Paul Beech of Armatherm discusses the importance of understanding where thermal bridging can occur in housebuilding projects, such as around balconies, and why the solutions available should not be overlooked.
When you think of thermal bridging, it’s most common that you’d be considering steel framework connections or balconies, but they’re much more prevalent than you might think. From the very top to the bottom of any building, there is opportunity for thermal bridges to cause detrimental issues, including structural damage and mould issues; which are widespread in UK homes and need to be addressed.
Not only is thermal bridging causing problems within the four walls of a building, but it can also contribute to increasing the carbon footprint of residential homes due to the increase in energy consumption to regulate temperatures and the energy lost via the bridged connection.
In a time where new homes on the market are being built quickly to meet demand, what are the dangers of overlooking issues such as thermal bridging?
A solution we’re seeing across the board to meet the ever-increasing housing demand is high rise apartments and flats. To combat issues with indoor air quality and allow homes to have access to fresh air, many of these buildings feature balconies, and these are a prime location for thermal bridging issues.
These thermal bridging issues occur due to the conductivity of the materials often used in balcony projects, such as steel and concrete. If not isolated properly, these can provide the ideal circumstances for thermal bridging and subsequent issues, such as condensation, damp and mould, which can lead to major health problems for residents.
But balconies are just one of the visible culprits. Behind the render and beneath the floors, thermal bridging can cause serious issues with far-reaching effects. Lintels, parapets, roof connections, slab edges, wall penetrations and even within masonry, are all areas that can undermine a home’s thermal envelope. Without the correct specification of thermal breaks, these junctions become weak spots, allowing warmth to escape and cold to creep in, or vice versa.
What’s more, the pressure to meet housing targets, especially in areas with high demand, means that some new-build homes are being delivered with speed prioritised over long term performance. According to the UK Green Building Council, around 80% of homes that will be in use in 2050 have already been built.
That means improving the performance of both new and existing homes is essential if the UK is to meet its net zero goals. Unfortunately, in the rush to build, thermal bridging is often left as an afterthought. It might not be visible on day one, but over time, it can lead to costly problems, both for homeowners and the wider environment.
It’s not just new builds that are at risk, either. The UK’s existing housing stock is among the oldest in Europe, and many of these properties are being retrofitted with new cladding, insulation or window systems. While these upgrades are vital for improving energy performance, they can unintentionally introduce thermal bridging where materials and systems meet.
If structural connections or fixings aren’t properly thermally isolated, the gains made in one area can be lost through bridging elsewhere. This is especially true in properties with solid wall construction, where remedial works often involve adding external or internal insulation that can clash with existing architectural details.
That’s where thermal breaks come into play. These engineered materials are designed to interrupt the flow of heat across junctions where conductive materials, like steel or concrete, would otherwise create a continuous path. By installing thermal breaks at key connection points, housebuilders and specifiers can improve a building’s thermal performance, reduce energy bills and mitigate the risks of condensation and damp, without compromising on structure or design intent.
Thermal breaks also play a valuable role in ensuring compliance. With regulations such as Part L tightening performance requirements and with greater scrutiny of SAP calculations and thermal modelling, failing to address thermal bridging can result in missed targets. Thermal bridging can account for up to 30% of a building’s heat loss, so overlooking it isn’t just a small oversight; it can be the reason a property fails to meet key efficiency standards.
And importantly, thermal breaks aren’t one size fits all product solutions. With the right approach and early design stage integration, solutions can be tailored to different build types, whether that’s new housing or sensitive retrofit projects.
As awareness of the issue grows, so too does the need to factor thermal bridging into early stage decisions, alongside insulation, fenestration and ventilation strategies.
In residential settings, whether you’re designing a compact block of starter homes, updating a Victorian terrace or planning a net zero neighbourhood, thermal breaks should be seen as an essential part of the toolkit. They help protect indoor air quality, reduce long term maintenance issues and contribute significantly to lowering emissions.
In short, they offer a low profile, high impact solution to one of the most persistent issues in building physics. It’s time for thermal breaks to be moved up on the agenda. While they may be hidden from view, their effects are anything but invisible.
Paul Beech is commercial director at thermal break specialist Armatherm