Pioneering Energy Efficiency with the Kalzip E-Clip / by Alexander Yolevski

Sustainable building envelopes have long been at the forefront of construction innovation, with a primary focus on reducing heat loss and promoting energy efficiency in both new and existing structures. One remarkable solution leading the charge in this endeavour is the fully patented E-Clip by Kalzip, now available through Exterior Technologies Group. This innovative E-Clip is designed to minimize thermal bridging within the Kalzip system, delivering a highly effective thermal insulation layer while also providing exceptional load-bearing capacity.

In response to the heightened requirements outlined in the statutory guidance document titled "Conservation of Fuel and Power: Approved Document L," Kalzip introduced its pioneering E-Clip two decades ago. Initially available only in a full-metal configuration, the updated version now offers an array of advantages due to its refined construction. The incorporation of a steel insert ensures unparalleled load-bearing capacity and stability, making the E-Clip an exceptional choice. This steel insert is crafted through injection molding with a glass fiber-reinforced, UV-resistant polyamide, composed entirely of recycled materials, thus bestowing the E-Clip with significantly reduced thermal conductivity when compared to its predecessor.

Proven Improvement in U-Value

Adhering to the prescribed U-values outlined in Approved Document L and anticipating forthcoming shifts in legislation aimed at enhancing energy efficiency and reducing greenhouse gas emissions, there is a growing need for sustainable, flexible, and thermally efficient roof constructions. The Kalzip E-Clip, enhanced and officially approved, presents a solution that enables the realization of various roof geometries while effortlessly meeting the required statutory guidelines.

Depending on the roof structure, the height of the E-Clips, and the thermal conductivity of the insulation, corresponding U-values can be achieved. For example, within a standard insulated Kalzip roof construction, the E-Clip boasts a U-value of less than 0.16 W/(m2K). Furthermore, with the addition of Kalzip's roof systems Duo Plus E and Duo E, these values can be further improved. When installed on walkable insulation, the thermal performance of the roof structure with the E-Clip can achieve U-values of less than 0.13 W/(m2K). In comparison to the thermal bridging effect of the metal clip, heat loss is approximately 30 percent lower for nearly all constructions employing Kalzip E-Clips.

Secure and Easy Installation

The development of the E-Clip also prioritized ease of installation, in addition to enhancing U-value performance. The steel insert not only ensures a stable clip with exceptional load-bearing capacity for the roof construction but also provides safety during installation. The torque-oriented SDK screws simplify and secure the installation of the E-Clips on various substrates. Thanks to the symmetrical clip head, the Kalzip profile sheet can be swiftly and easily installed. Moreover, the polyamide coating of the clips allows the Kalzip sheets to expand and contract freely, streamlining the installation of lengthy Kalzip sheets. In terms of fire performance, the Kalzip system has achieved a classification of B[Roof]T4 when tested to EN13501-5.

With the Kalzip E-Clip, an array of roof geometries can be realized without compromising on compliance with the legal requirements set forth in the German Energy Savings Ordinance (GEG). Exterior Technologies Group is proud to offer this exceptional solution, enabling architects and builders to create energy-efficient structures with ease and confidence.