Thermal bridges - avoiding momentous planning errors
What is a thermal bridge/ thermal break?
Thermal bridges and themal breaks are important concepts in the field of building thermics. But what exactly are they and what impact do they have on energy consumption and living comfort?
A thermal bridge occurs when there is a break or weak spot in the building envelope that allows heat to unintentionally escape to the outside or cold bridges to enter the building.
Thermal breaks are areas where thermal insulation is inadequate and cold can enter the building from the outside.
In these areas, heat can therefore be transported to the outside or cold to the inside more quickly, possibly leading to heat loss. This inevitably has a negative impact on the energy efficiency of buildings.
Component solutions from B.T. innovation
The types of thermal bridges can be different. Material-related thermal bridges are caused by poorly insulated building materials, for example, while structural thermal bridges are due to structural details such as balconies or projections. Geometrically induced thermal bridges occur when the shape of a building or the arrangement of building components leads to energy losses.
To minimize the negative effects of thermal bridges and cold bridges, it is important to take appropriate measures. One effective method is to insulate cold bridges to reduce heat loss and lower energy consumption. In addition, structural thermal bridges should be avoided by considering appropriate building design and construction.
Examples of thermal bridges are often found near windows, at roof junctions, or around ceiling tiles. To ensure a comfortable indoor climate and avoid possible structural damage, it is important to identify thermal bridges at an early stage and take appropriate measures.
Our experienced team of experts is available to help you identify and resolve thermal bridging issues. Contact us today to learn more about how you can eliminate thermal bridges and cold spots in your building.
In precast concrete construction, B.T. innovation comes up with intelligent and effective system solutions for thermal insulation.
Use of ThermoPin and DowaTherm for energy-efficient construction
Concrete is an ideal building material for monolithic use on construction sites as well as for precast production, but due to its high thermal conductivity and building physics parameters, it places high demands on building material connections in the structural solution of thermal bridge-free wall and precast systems.
For the thermal decoupling of these wall systems, especially for double and thermal walls as well as sandwich elements, B.T. innovation has launched simple and highly effective solutions for avoiding thermal bridges.
The effect of thermal bridges
Thermal bridges are usually associated by the consumer with increased energy consumption. In addition to this effect, which increases the required heating power and thus energy costs and environmental pollution, there are other unpleasant effects:
- Due to the increased outflow of heat to the outside in the area of the thermal bridge, the surface temperature of the wall decreases. This reduces the comfort in the room, a “draft” can be felt.
- Where the surface temperature of the interior wall cools, the warm room air condenses and condensation forms on the wall surface. In the long term, this creates a climate that favors mold growth. Room corners, radiator niches, but also window reveals are at risk.
- If the moisture penetration of the building components continues, the building structure suffers. The permanently high moisture content in the building component causes the surface temperature to drop more and more, which means that even more moisture can condense (sealing concrete)
Thermal bridges in buildings can cause great damage. Therefore, the primary goal in planning and execution is an exterior wall with as few thermal bridges as possible. By using optimized product solutions such as the systems from B.T. innovation, the prerequisites for energy-efficient slimline construction are met.
Forms of thermal bridges
The largest proportion of thermal leaks in the building envelope are the so-called linear thermal bridges. These can in turn be divided into three groups:
- Material-related thermal bridges occur when the thermal conductivity changes within a building component. Typical examples of this form of thermal bridges are reinforced concrete columns, ring beams, window lintels (seal windows) or cantilevered reinforced concrete parts.
- Geometric thermal bridges appear where there are large differences in size between the inner surface (heat-absorbing) and the outer surface (heat-dissipating) in relation to the surface area. Typical examples are building corners and edges.
- Finally, the constructive thermal bridge is closely linked to the material-related thermal bridge and can often hardly be avoided. Roller shutters or rainwater downpipes located in the ETICS belong to this category. Constructive thermal bridges also frequently occur on balconies.
In addition to the main categories mentioned above, there are also point thermal bridges that can be caused by fasteners or single cantilevers. Three-dimensional thermal bridges can occur in the corners of the room. This is where the risk of mold is greatest, as a very low temperature field can develop. So-called convective thermal bridges are caused by leaks in the components enclosing the room, component joints or installation guides.
Thermal bridges due to faulty execution
If individual construction details are executed improperly, gaps in the thermal insulation and thus heat losses occur. Typical construction defects in this area are, for example, incomplete compartment insulation, gaps in masonry with mortar filling (joining concrete) in monolithic exterior walls, insulation panels not laid without joints in the thermal insulation composite facade or mortar residues in contact with the material in the core insulation level of double-shell exterior walls (concrete renovation).
How can thermal bridges be avoided?
The ThermoPin system from B.T. innovation has been developed for the design and manufacture of reinforced concrete walls with self-supporting facing shells, for sandwich walls or monolithic multi-layer walls.
Advantages at a glance – BT ThermoPin:
- Price stability versus steel
- Thermal decoupling of wall systems
- Corrosion resistant
- Not thermally conductive
- Non-magnetic conductive
- Does not form electric fields
- Eliminates steel connections in multi-layer reinforced concrete elements
The ThermoPin system from B.T. innovation has been developed for the construction and manufacture of reinforced concrete walls with self-supporting facing shells, for sandwich walls or monolithic multi-layer walls.
Due to the geometric shape of the GRP anchors and the specified installation position, they guarantee the statically required bond of the shells for all occurring load cases from temperature influence, wind, earth and concreting pressure and at the same time, through the combination of tension and compression rods, take over the dead load of the facing shells. The rod-shaped GRP anchor is conically shaped at the ends by a special process, and thus contains the prerequisites for absorbing high pull-out forces. In addition to the special shaping at the rod ends, the ThermoPin has a plastic ring firmly connected to the GRP body, which serves to fix the insulation layer and as a spacer and water barrier.
With DowaTherm and ThermoPin – for the efficient production of reinforced concrete components
Due to the metal-free fibre composite, the DowaTherm and ThermoPin elements are not susceptible to corrosion, do not conduct heat and, with the possible low concrete coverings, provide the prerequisites and advantages for lean and efficient production of reinforced concrete components and their use in demanding construction projects.
Thus, for manufacturers of double and thermal walls, a product was made available in the form of the DowaTherm system that combines several advantages.
Advantages at a glance – BT DowaTherm:
- Corrosion resistant
- No problems with concrete cover
- Light processing
- Time saving during processing
- No thermal bridges
- Specially suitable for thermal wall production
- Rational operational use due to clear and space-saving storage
- Adaptability for any wall thickness with minimum effort
- Price stability through independence from the price of steel
- No influence by magnetic fields
The flexible spacers, which consist of a plastic-coated fibre composite, ensure exact compliance with the specified element thicknesses and can be used safely and stably in the production process thanks to simple connections with the lower reinforcement layer. Expanded by the terminal system, DowaTherm elements are very rational as individual components and, moreover, effective and clear to use with the smallest space requirement.
The thermal transmittance coefficient, also known as U-value, is an important parameter for assessing the thermal insulation of building components such as windows, walls, or roofs. But what exactly does the U-value mean and how is it calculated?
The U-value indicates how much heat is lost through a building component per unit time and per temperature difference between the interior and exterior. It is closely related to the thermal conductivity of the material. The lower the U-value, the better the thermal insulation of the component.
To calculate the U-value, the thermal conductivity of the material is used. Thermal conductivity refers to how well a material conducts heat. By combining the thermal conductivities of different materials and the thickness of the building component layers, the U-value can be determined. There are also online calculators available to help you calculate the U-value for specific building components such as windows.
Standard windows often have a specific U-value that serves as a reference value. A lower U-value indicates better thermal insulation and reduced heat loss. The unit of U-value is watts per square meter and Kelvin (W/m²K).
Understanding the U-value is crucial for evaluating the energy efficiency of buildings and implementing appropriate measures to improve thermal insulation. A lower U-value helps reduce energy consumption and improve living comfort.
Our experienced team of experts is available to assist you in determining the U-value for your building components and providing tailored solutions for thermal insulation. Contact us today to learn more about how you can optimize the U-value and enhance the energy efficiency of your building.