Cold Bridging: Causes, Solutions, and the Difference from Thermal Bridging

1. Building elements with high thermal conductivity: Materials such as metal, concrete, or uninsulated masonry have higher thermal conductivity than insulation materials. When these materials come into direct contact with the interior and exterior environments, they create paths for heat to escape or enter, causing cold bridging.
2. Structural components: Structural elements, such as steel beams, concrete columns, or wood studs, can act as thermal bridges since they conduct heat more readily than the surrounding insulation. These elements often penetrate the building envelope, allowing heat to flow across them.
3. Wall ties and fasteners: Metal wall ties or fasteners used in masonry construction can conduct heat and create thermal bridges if not properly insulated or spaced. They can provide a direct path for heat transfer between the interior and exterior of the building.
4. Window frames and sashes: Window frames made of materials with high thermal conductivity, such as aluminum, can contribute to cold bridging. Inefficient or improperly installed windows can allow heat to escape, resulting in cold spots near the window frames.
5. Junctions and corners: Corners, junctions, and intersections between different building components, such as walls, floors, and roofs, are areas prone to cold bridging. These areas often require careful detailing and insulation techniques to minimise thermal bridging.
6. Inadequate insulation or gaps: Insufficient insulation or gaps in the insulation layer can lead to thermal bridges. These gaps can occur during installation or over time due to settling, degradation, or improper sealing. Any breaks or interruptions in the insulation can create pathways for heat transfer.
7. Poor construction practices: Inaccurate installation techniques, lack of attention to detail, and insufficient quality control during construction can contribute to cold bridging. Improper sealing of joints, gaps, and penetrations can lead to thermal bridges.

By understanding the causes of cold bridging, builders, architects, and homeowners can take proactive measures to minimise its occurrence and improve the energy efficiency and thermal comfort of buildings. Proper insulation, careful detailing, and selection of materials with lower thermal conductivity can help prevent or reduce cold bridging.

1. Building envelope design: During the design phase, consider ways to minimise thermal bridging. Opt for a well-insulated and continuous building envelope that includes insulation layers without any interruptions or gaps.
2. Thermal breaks: Incorporate thermal breaks into the building’s structure. These are materials with low thermal conductivity placed between components that conduct heat, such as concrete slabs, steel beams, or window frames. Thermal breaks interrupt the thermal path, reducing heat transfer and minimising thermal bridging.
3. Insulation: Ensure proper insulation throughout the building. Use insulation materials with low thermal conductivity, such as foam boards, mineral wool, or cellulose insulation, to create a continuous thermal barrier. Pay attention to areas prone to thermal bridging, such as wall studs, corners, and junctions between different building elements.
4. Continuous insulation: Implement continuous insulation techniques, such as exterior insulation systems or insulated sheathing, which provide a continuous layer of insulation across the building envelope. This helps to mitigate heat loss and reduce thermal bridging.
5. Improved construction techniques: Train construction crews to follow best practices in insulation installation. Attention should be given to details such as properly sealing gaps, joints, and penetrations in the building envelope to minimise air leakage and thermal bridging.
6. Use of thermal breaks in windows and doors: Select windows and doors with built-in thermal breaks or install thermal break strips around the frames. This helps to minimise heat transfer through these areas and reduces thermal bridging.
7. Structural design considerations: If possible, explore alternative structural designs that reduce the need for structural elements with high thermal conductivity, such as steel beams or columns. Opting for materials with better insulation properties, such as wood or insulated concrete forms, can help mitigate thermal bridging.
8. Energy modeling and analysis: Utilise energy modeling software to evaluate and identify areas of potential thermal bridging. This allows for targeted design modifications and optimisations to minimise heat transfer and improve overall energy efficiency.

Remember, thermal bridging can occur in various areas of a building, including walls, roofs, floors, and foundations. By implementing these strategies and considering thermal bridging prevention from the early stages of design and construction, you can significantly enhance the energy performance and thermal comfort of the building.