Thermal bridging can reduce the efficiency of a building and lead to moisture-related issues like mold, unwanted expansion and contraction of building materials. This challenge is especially common in commercial and industrial buildings, but effective solutions exist to minimize its impact. Let’s explore what causes these thermal bridges and how insulated metal panels (IMPs) can help create a more energy-efficient building envelope.
In construction, a thermal bridge refers to the areas where heat can move from the inside to the outside of the building and vice versa. Thermal bridges occur when materials that are more conductive form a “bridge” between the interior and exterior of the building. Because heat flows towards colder areas, it will move towards the exterior of the building when it’s colder outside and to the interior of the building when it’s colder inside.
One common way that thermal bridging occurs is where wall studs meet the interior and exterior walls. Heat travels through the studs to either the inside or outside of the building, resulting in heat loss if it’s colder outside or drawing heat inside if the interior is colder.
Other areas where thermal bridging occurs is where other materials, like steel or concrete, interrupt the insulation or where other building elements connect and allow heat to transfer.
Understanding how to prevent thermal bridging is essential to constructing an energy efficient and comfortable building. Remedying thermal bridging after construction is complete can be a disruptive and costly process, so mitigating the risk during the design and construction phases is essential.
Because thermal bridging allows heat to transfer, it results in the heating and air conditioning systems working harder to maintain the desired temperature. Other consequences of thermal bridging include condensation, damage from freeze-thaw cycles, moisture and mold issues, cold or warm spots that can lead to damage, increased heating and cooling costs, and discomfort for those occupying the building.
Thermal bridging can negatively affect the effective R-value, also referred to as thermal resistance, of the wall assembly. In a controlled setting, the nominal’s R-value may measure higher than its effective R-value (the amount it actually insulates in a real-world application with other factors at play). The higher the R-value, the better its ability to slow heat transfer.
The U-value measures the rate at which heat is transferred through a material and reveals the thermal efficiency of the building envelope, including walls, doors, windows, and roofs. A lower U-value means a lower rate of thermal transmittance and a higher U-value means a higher rate of thermal transmittance.
Thermal bridging can reduce the effectiveness of the insulation, resulting in a lower than desired effective R-value. This means the wall assembly isn’t insulating as well as it should. It can also result in the building having a higher U-value and allowing more heat loss which can increase utility bills and result in the other issues listed above. So, preventing thermal bridging results in a more energy efficient building.
Insulated metal panels provide superior insulation for a building, thus reducing the thermal bridging effect. IMPs consist of an insulation core sandwiched between two metal panels. Norbec offers two types of insulation cores — mineral fiber and polyisocyanurate (PIR). The type of core you choose will depend on the building characteristics that meet building code standards. For instance, a mineral fiber core is highly fire resistant while a PIR core has a higher R-value.
The continuous layer of insulation in our NOROC® and NOREX® panels results in reduction of thermal bridging.
The pressure-equalized rainscreen joint and factory-applied butyl joint sealer ensures a tightly sealed building envelope. The insulation in IMPs prevents thermal bridging by breaking the connection between building elements like studs and the interior and exterior wall covering to provide effective insulation and superior energy efficiency. Norbec products also use hidden fasteners to further minimize thermal bridging.
Both systems are suitable for different architectural wall arrangements and offer a cost effective cladding solution that is quick to install with our exclusive fastening system. These panels can form to the shape of the building and come in a wide range of colors to create a stunning exterior. Both systems are suitable for interior and exterior applications.
Contact the experts at Norbec today to discuss how our products reduce the effects of thermal bridging.