Thermal Bridging Assessments

Thermal modelling involves creating a detailed computational representation of a building's thermal performance. Using specialized software, we simulate heat transfer through various building elements, identifying potential weaknesses and optimizing designs for energy efficiency. This process allows us to predict how a building will perform in real-world conditions, before construction even begins.

Psi values, also known as linear thermal transmittance, quantify the heat loss through non-uniform building junctions, such as wall-floor connections, window frames, or corners. These "thermal bridges" can significantly impact a building's overall energy performance, even if the individual components have good U-values.

Including Psi values in energy assessments allows for a more accurate calculation of a building’s heat loss, ensuring precise EPC ratings and full compliance with building regulations such as Approved Document L (Part L). 

Accurately modelling thermal bridges using precise Psi-value calculations can deliver significant cost savings by demonstrating improved energy performance compared to default values. This often allows for a reduction in the amount of main fabric insulation required, lowering material and construction costs. In addition, detailed thermal bridge modelling supports enhanced compliance with Building Regulations Part L and helps achieve or exceed energy efficiency targets.

By identifying and addressing thermal bridges, we can significantly reduce a building’s heating demand, lowering energy bills and minimizing its carbon footprint. Additionally, accounting for Psi values helps prevent cold spots that can cause surface condensation and mould, enabling the design of junctions that maintain comfortable and healthy indoor temperatures. Incorporating Psi values is therefore essential for achieving energy-efficient, sustainable, and durable buildings.

Our thermal modelling experts use industry-leading software to create 2D and 3D models of building junctions. We input detailed material properties and construction details to accurately simulate heat flow and determine the Psi value for each specific junction. This rigorous approach ensures precise and reliable results.BR 497 Compliance

Our thermal modelling methodologies are fully compliant with BR 497 (Conventions for calculating linear thermal transmittance and temperature factors), ensuring that our calculations and recommendations are in line with industry best practices and regulatory requirements. This commitment to established standards provides you with confidence in the accuracy and reliability of our analysis.

Temperature Factors (fRsi)

​The temperature factor (fRsi) is a dimensionless value that indicates the risk of condensation and mould growth at a given internal surface. It compares the internal surface temperature at a thermal bridge to the internal and external air temperatures. A lower fRsi value indicates a higher risk of condensation.

A condensation risk assessment evaluates temperature factors to determine whether internal surfaces are likely to drop below the dew point, which can lead to condensation. Ensuring a sufficiently high fRsi value is crucial for preventing mould growth, promoting a healthier and more comfortable indoor environment. Compliance with building regulations often mandates minimum fRsi values for specific building elements, helping to safeguard occupant comfort, health, and long-term building performance. Conducting thorough assessments supports the creation of energy-efficient, safe, and durable buildings.

Our thermal modelling analysis simultaneously calculates temperature factors alongside Psi values. By simulating temperature distributions across junctions, we can pinpoint areas susceptible to cold spots and provide recommendations to improve surface temperatures and reduce condensation risk.

By partnering with Award Energy, you can achieve highly energy-efficient buildings that are comfortable, healthy, and compliant with the latest standards. Contact us today to discuss your project.