In recent years, modular construction has refined to become one of the most efficient methods of construction in the industry. It hosts a range of benefits that on-site construction struggles to compete with, such as flexible design options that can be added, removed, or reconfigured with relative ease to meet changing needs or rapid expansion requirements.
The process is continually evolving to improve efficiency standards further, but with buildings that fit together like a jigsaw, there are a number of opportunities for energy loss through thermal bridging as steel framework is joined.
Just how detrimental can thermal bridging be to modular buildings that already boast impressive energy statistics? Although the credentials may look impressive on the factory foreground, how much can these differ once a structure is assembled and in situ? Paul Beech, Commercial Director of thermal breaks specialist, Armatherm, discusses the importance of considering thermal bridging in modular buildings, and the negative impacts that can arise from overlooking crucial thermal breaking solutions.
According to a report by the UK Parliament, the modular construction market is expected to grow by 6.3% annually, reaching a value of £12 billion by 2025. This fast growth is down to the benefits modular building offers, and the speed in which projects can be completed. While site preparation and foundation works are ongoing, modules can be simultaneously manufactured in a factory. This parallel process can shorten project timelines by 30-50% compared to traditional construction methods, and as much of the construction occurs in a controlled factory environment, weather-related delays are minimised, ensuring a more predictable schedule.
In addition, building modules in a factory allows for efficient use of materials, reducing waste and improving quality control. The streamlined, assembly-line nature of modular construction requires less on-site labour, translating to lower labour costs and fewer expenses related to site management and logistics – this also relates back to predictable schedules and faster turnaround times, as reduced workforces means less chance of inconsistencies like sick days or annual leave.
When it comes to sustainability, modular buildings possess perhaps some of the most impressive statistics compared to other construction methods. Creating elements in controlled settings means there is greater precision. For example, areas leaking air can be more easily sourced, and sealing techniques can be effectively implemented in a factory, ensuring that joints and connections are airtight. This reduces drafts and improves the building’s overall thermal envelope.
However, in modular construction, where modules are prefabricated and then joined on-site, the steel framework can become a significant source of thermal bridging, both. This results in heat being transferred through the material at a much faster rate than through the surrounding insulated areas, leading to increased energy consumption and reduced overall energy efficiency of the building. This can also occur in the foundations where the concrete foundations and steel frame meet.
The importance of addressing thermal bridging cannot be overstated. It can account for a significant portion of heat loss in a building — up to 30% in some cases. This not only affects the building’s energy performance but can also lead to condensation issues, mould growth, and deterioration of building materials, ultimately compromising the structural integrity and indoor air quality of the building.
In the context of modular construction, incorporating effective thermal breaks is essential. Thermal breaks are materials with low thermal conductivity that are used to interrupt the continuous path of heat flow, thereby reducing the rate of heat transfer. Armatherm, for example, provides solutions that can be integrated into the steel framework of modular buildings to mitigate thermal bridging effects. Its FRR structural thermal break material provides a combination of low thermal conductivity and high compressive strength and has been used in hundreds of structural steel framing connections transferring load in moment and shear conditions.
In conclusion, while modular construction offers numerous benefits in terms of efficiency, speed, and sustainability, addressing thermal bridging is crucial to maximising these advantages. Effective thermal breaks are essential in maintaining the energy performance of modular buildings, preventing heat loss, and avoiding the associated issues of condensation and material degradation. By incorporating robust thermal break solutions and ensuring quality design and installation practices, modular construction can continue to lead the way in delivering high-performance, energy-efficient buildings.