When evaluating the thermal performance of a commercial building, insulation thickness is only part of the equation. The way exterior cladding is attached to the building can also have a meaningful effect on heat transfer through the wall.
Thermal clips are commonly used in modern commercial cladding systems to support exterior sub-framing while maintaining space for continuous insulation. By reducing the amount of conductive material passing through the insulation layer, a properly designed thermal clip system can help improve whole-wall thermal performance. For building owners and project teams, this can influence energy use, HVAC demand, indoor comfort, and long-term operating costs.
What Are Thermal Clips?
Thermal clips are attachment components used to connect exterior cladding or sub-framing back to the building structure while allowing space for continuous exterior insulation.
In many commercial wall assemblies, the cladding needs to be securely attached through or around the insulation layer. Traditional steel girts can provide this support, but steel is highly conductive. When continuous metal components create direct paths through the insulation, heat can move through the wall more easily.
Thermal clips are designed to reduce this effect while still providing the structural support required for the exterior cladding system. Depending on the system, this can be achieved through clip geometry, reduced metal contact, lower-conductivity materials, or a combination of these features.
How Thermal Bridging Affects Wall Performance
Thermal bridging occurs when a conductive material creates an easier path for heat to move through an insulated wall assembly. Steel framing, girts, fasteners, and attachment components can all contribute to this effect.
During colder weather, interior heat can move outward through these conductive areas. During warmer weather, exterior heat can move inward, increasing the amount of cooling required to maintain comfortable indoor temperatures.
This is why the published R-value of an insulation product does not always represent the actual performance of the finished wall. A wall can contain a substantial amount of insulation and still perform below expectations if the insulation is repeatedly interrupted by conductive components.
For larger commercial and industrial buildings, even modest differences in whole-wall performance can affect energy use over the life of the building.
Why Effective R-Value Matters
When comparing wall assemblies, building owners and project teams should look beyond insulation thickness and consider the effective R-value of the complete system.
Effective R-value takes into account the impact of framing, clips, girts, fasteners, and other materials that influence heat transfer through the wall. Two commercial wall cladding systems can use the same insulation product and thickness while performing differently because of the way the cladding is attached.
For example, a wall assembly with continuous steel girts may create more thermal bridging than one that uses thermally improved clips with intermittent attachment points. The insulation may be identical, but the overall thermal performance can still be different.
Looking at the complete wall assembly provides a more realistic picture of how the building envelope is likely to perform in service.
How Thermal Clips Support Continuous Insulation
Continuous exterior insulation is installed across the exterior side of the wall structure to create a more consistent thermal layer around the building. This helps reduce the thermal interruptions that occur when insulation is installed only between framing members.
The challenge is that the exterior cladding still needs to be securely attached to the building structure. The attachment system therefore has to pass through or interact with the insulation layer without reducing its effectiveness more than necessary.
Thermal clips help address this issue by limiting the amount of conductive material crossing the insulation. When properly designed and installed, they allow the insulation to retain more of its intended thermal performance while still supporting the cladding and sub-framing.
This is especially relevant in metal cladding and other architectural wall systems where continuous exterior insulation forms an important part of the overall building-envelope design.
How Thermal Clips Can Affect Energy Use and Operating Costs
Heat that moves through the building envelope has to be replaced or removed by the building’s mechanical systems. During winter, heat lost through exterior walls increases heating demand. During warmer months, unwanted heat entering the building can increase cooling demand.
Reducing thermal bridging helps limit this heat transfer, which can reduce the amount of energy required to maintain indoor temperatures.
The actual savings will vary from one building to another. Building size, wall area, climate, occupancy, operating hours, HVAC efficiency, insulation levels, and energy prices all affect the result. However, on larger commercial buildings, improvements in whole-wall performance can become significant when applied across thousands of square feet of exterior wall.
For building owners, this is one reason thermal clips should be considered as part of the overall performance of the wall assembly rather than as a minor attachment detail.
Are All Thermal Clip Systems the Same?
Thermal clip systems can vary considerably in both thermal and structural performance.
Factors such as clip material, geometry, spacing, fastener frequency, insulation thickness, and the amount of metal passing through the insulation can all affect thermal performance. Structural requirements also need to be considered, including cladding weight, wind loads, building height, substrate conditions, and sub-framing design.
A thermally efficient clip system still has to provide reliable support for the cladding. This means thermal performance should be considered together with the engineering and installation requirements of the complete cladding system.
Thermal Clips Are Only One Part of Wall Performance
A thermally efficient attachment system can improve the performance of a wall assembly, but it cannot compensate for poor detailing elsewhere in the building envelope.
Insulation needs to remain continuous and properly fitted, while air and water-control layers need to be carefully detailed around windows, doors, penetrations, parapets, and roof-to-wall transitions. Gaps in insulation or poorly sealed transitions can reduce the effectiveness of an otherwise well-designed wall.
Installation quality also matters. Whether the project involves architectural metal cladding, another panel system, or a broader building-envelope retrofit, the individual components need to work together as a complete assembly.
What Should Building Owners Ask?
When reviewing options for a commercial wall or recladding project, it is useful to ask how the proposed assembly performs beyond the stated insulation R-value.
Key questions include:
- What is the effective R-value of the complete wall assembly?
- How does the attachment system reduce thermal bridging?
- Has the proposed wall assembly been thermally modelled or tested?
- How does clip spacing affect thermal and structural performance?
- Does the system meet the required wind and cladding loads?
- How will insulation and air-barrier continuity be maintained at transitions?
- How will installation quality be verified during construction?
These questions help shift the discussion away from individual product specifications and toward the actual performance of the finished building envelope.
Final Thoughts
Thermal clips may be hidden behind the finished exterior of a building, but they can have a meaningful effect on wall performance. By reducing conductive heat transfer through the cladding attachment system, they can help continuous insulation perform more effectively and reduce unnecessary heating and cooling demand.
For building owners, consultants, developers, and contractors, the key is to evaluate the complete wall assembly rather than focusing only on insulation thickness. The insulation, thermal clips, sub-framing, membranes, and commercial cladding all need to work together to achieve the intended thermal and structural performance.
Mack Kirk installs commercial cladding and building-envelope systems throughout British Columbia, working with contractors, consultants, developers, and building owners on new construction and retrofit projects.
