Energy efficiency has always been a priority in the world of building design and construction, but the issue is becoming increasingly critical as we move into 2025 with factors such as rising energy costs and pressing sustainability challenges.

“The green transition of the building value chain can unlock $1.8 trillion in market opportunities globally according to the World Economic Forum and Boston Consulting Group, as well as significant social and environmental value.

“Energy efficiency is one of the easiest and most cost-effective ways to combat climate change, reduce energy costs for consumers, and improve the competitiveness of U.S. businesses. Energy efficiency is also a vital component in achieving net-zero emissions of carbon dioxide through decarbonization,” explains the U.S. Department of Energy.

As we strive to create more sustainable and comfortable structures, one challenge that continues to plague builders and designers is thermal bridging.

This phenomenon can significantly impact a building's energy performance, leading to increased costs and reduced comfort for occupants.

In this article, we'll explore the concept of thermal bridging, its implications, and how Insulated Metal Panels (IMPs) offer an effective solution to this persistent problem.

Understanding Thermal Bridging

Thermal bridging – also called “cold bridge” or “heat bridge” -- is essentially the area of a building where heat transfer is significantly higher than the surrounding materials, often because of breaks in insulation or components, creating a path for heat to easily escape or enter the building.

To put it another way, thermal bridging occurs when heat flows through a path of least resistance in a building's envelope, bypassing the insulation and creating a weak point in the thermal barrier.

This phenomenon typically happens where there's a break in the insulation or where materials with higher thermal conductivity penetrate or compress the insulating layer.

“The first thing to know about thermal bridging is that it’s nothing new,” writes Andy Lundberg for Passive House + Sustainable Building. “Early cave dwellers, who made excellent use of cliff-face orientation, thermal mass and form to create comfortable environments in all seasons, didn’t crack the thermal bridging issue either.”

How Thermal Bridging Occurs

Common examples of thermal bridges include:

• Wall studs interrupting insulatio
• Steel beams or concrete columns extending from interior to exterior
• Window and door frames
• Balcony slabs protruding through exterior walls
• Roof-wall junctions

In these areas, heat can easily transfer between the interior and exterior of a building, compromising its overall thermal performance.

“What we do know is that all buildings suffer from the effects of thermal bridging, and that is completely unavoidable. What we can do through knowledge, good design and use of finite-element analysis is reduce its effects insofar as reasonably practicable, sensible and affordable,” writes Lundberg.

Measuring Thermal Bridging

Thermal bridging is typically quantified using two key metrics:

• Psi (Ψ) Value: This measures linear thermal transmittance, expressed in W/m·K. It represents the additional heat flow through a linear thermal bridge, such as the junction between a floor and an external wall. Higher Psi values indicated greater heat loss through the thermal bridge.
• Chi (χ) Value: This measures point thermal transmittance, expressed in W/K. It's used for localized thermal bridges, like a steel beam penetrating an insulated wall.

These values are calculated using specialized thermal modeling software, which analyzes the heat flow through building components and junctions.

Thermal bridging can also be determined through laboratory testing using heat flux sensors and thermography or via in-situ measurements using infrared thermography and heat flux meters.

The Impact of Thermal Bridging

Thermal bridging has a big impact on buildings from energy loss to comfort:

Energy Loss and Costs

Thermal bridging can account for up to 30 percent of a building's total heat loss. This significant energy leakage translates to higher heating and cooling costs, as HVAC systems must work harder to maintain comfortable indoor temperatures.

Comfort and Health Concerns

Beyond energy inefficiency, thermal bridges can create cold spots on interior surfaces, leading to condensation and potential mold growth. This not only affects occupant comfort but can also pose health risks, particularly for those with respiratory conditions.

Building Performance

Thermal bridging can significantly impact a building's overall energy performance. As building codes become more stringent and energy awareness increases, addressing thermal bridging becomes crucial for meeting regulatory requirements and achieving desired energy ratings.

Why Builders and Designers Care

The growing focus on thermal bridging stems from several factors:

• Stricter Energy Codes: As building regulations evolve to prioritize energy efficiency, designers must pay closer attention to thermal bridging to meet performance standards.
• Cost Savings: Reducing thermal bridging leads to lower energy consumption and operational costs over a building's lifetime.
• Occupant Comfort: Eliminating cold spots and potential condensation areas improves overall comfort and indoor air quality.
• Sustainability Goals: Minimizing heat loss through thermal bridging helps reduce a building's carbon footprint, aligning with broader sustainability objectives.

“As more stringent legislation and energy awareness lead to increased insulation levels in walls, roofs and floors, heat losses due to thermal bridging become increasingly important,” says the BRE Academy, an institution that focuses on science-led training in sustainability.

Insulated Metal Panels: A Comprehensive Solution

Insulated Metal Panels (IMPs) have emerged as a highly effective solution to the thermal bridging problem.

What Are IMPs?

IMPs are prefabricated building components consisting of two metal facings bonded to an insulating foam core. They serve as both the exterior and interior finishes while providing superior insulation.

Green Span Profiles American-made IMPs, for example, are built by a continuously poured-in-place process binding interior and exterior corrosion-resistant steel facings to a polyisocyanurate insulating foam core.

These innovative building components offer a range of benefits that address thermal performance and beyond.

Unique Features of IMPs

IMPs offer some unique features compared to other traditional building materials:

• Continuous Insulation: IMPs provide an uninterrupted layer of insulation across the building envelope, significantly reducing thermal bridging.
• High R-Value: The foam core offers excellent thermal resistance per inch, outperforming many traditional insulation materials.
• Airtight Construction: The interlocking design of IMPs creates a tight seal, minimizing air leakage and further enhancing energy efficiency.
• Reduced Complexity: IMPs simplify the building envelope by combining multiple components (exterior finish, insulation, air barrier, and vapor retarder) into a single product.

How IMPs Solve Thermal Bridging

Let’s examine how IMPs solve our thermal bridging problem:

• Minimized Penetrations: The large panel sizes and integrated fastening systems reduce the number of thermal bridges created by fasteners and joints.
• Factory-Controlled Quality: IMPs are manufactured under controlled conditions, ensuring consistent insulation thickness and performance.
• Thermal Break Design: Many IMP systems incorporate thermal breaks at panel joints, further reducing heat transfer.
• Versatility: IMPs can be used for walls, roofs, and ceilings, providing a comprehensive thermal envelope solution.

“The buildings of today must satisfy a supreme standard; they are called upon to achieve high performance: to be resilient, healthy, and energy efficient,” says an IMP industry webinar. “Building science has given us a focused modern design emphasis on the building envelope in response to the movement of thermal, air, water, and vapor conditions. These demands elicit dramatic changes to building envelope designs and the components used within.”

The Green Span Profiles Advantage

As a leading manufacturer of American-made IMPs, Green Span Profiles is at the forefront of addressing thermal bridging challenges. Our state-of-the-art IMPs offer:

• Industry-leading R-values for maximum thermal efficiency.
• Precision-engineered joint systems to minimize thermal bridging.
• A wide range of finishes and profiles to meet diverse architectural needs.
• Rigorous quality control to ensure consistent performance.
• Expert technical support to assist with design and installation.

By choosing Green Span Profiles IMPs, you are investing in a comprehensive solution to thermal bridging that enhances energy efficiency, occupant comfort, and building performance.

Contact Green Span Profiles today to learn how our innovative IMP solutions can revolutionize your building's thermal performance and energy efficiency