Cladding attachment solutions are practical factors in creating more efficient buildings for modern architecture. The use of external installed cladding systems such as ACM panels is becoming increasingly common in the world. Architects use these products to meet new energy standard requirements. Commonly referred to as rain screens or exterior insulations, builders continuously install these materials outside the primary structure.

Cladding materials are generally more thermally efficient than the insulation placed between the inboard of the structural system. Additionally, cladding attachment solutions provide significant advantages for durability and thermal comfort. As a result, investors and designers pay greater attention to the design of thermally efficient cladding attachment solutions. Thus, manufacturers have produced several practical systems for the market in recent years. These attachment options include sub girts, rail systems, long screws, ties, intermittent clips and other engineered supports.

The greatest challenge that contractors and designers face is selecting and evaluating the suitable cladding strategy for their upcoming projects and understanding the implications of their options on thermal performance, installation methods, and system costs.

Energy Standards and Exterior Insulation

There are different energy standards and codes in power across Canada and America for commercial and residential buildings. The two well-known energy codes are National Energy Code for Buildings (NECB) and the International Energy Conservation Code (IECC). However, ASHRAE Standard is the most commonly referred building and energy code in most Canadian provinces. Different adaptations and versions of these standards are in effect in most areas.

While various versions and adaptations of these regulations and codes are enforced in different provinces, each requires consideration for the effectiveness of installed cladding and thermal bridging. Exterior cladding materials, including various types of ACM panels, showcase efficient and cost-effective methods to provide thermal performance improvement and meet all regulations requirements. However, the effectiveness of this particular approach depends on the selection of thermally efficient cladding attachment solutions. The attachment solution can be a significant thermal bridge to reduce exterior insulation performance by as little as 5% to 10 % for modern high-performance systems.

Cladding Attachment Solutions Requirements

There are several requirements for choosing the most efficient cladding attachment solutions for a building. It is recommended to consider all factors for achieving the best results. Followings are the cladding attachment solutions requirements that designers and contractors should know:

  • Gravity loads (cladding materials weight)
  • Wind loads
  • Seismic loads
  • The Back-up Wall Construction Material (wood, steel, concrete, concrete blocks)
  • Attachment points back into the building’s structure with various materials such as studs, slab edges, and sheathings
  • Exterior insulation thickness
  • Utilization of rigid, semi-rigid, or spray-applied system
  • The ability of fastening cladding supports directly through the face of the insulation panel
  • The ability to fit the semi-rigid or spray-applied system tightly around the supports and their ease of installation
  • Tolerable thermal efficiency loss orientations and requirements from supports
  • Attachment solutions location and direction for the cladding system, whether it is paneled, vertical or horizontal
  • Details required for attachment of cladding material ar corners, penetrations and returns
  • Combustibility requirements (this factor is essential)
  • Dimensional tolerance adaptation
  • Allowable thickness for walls

The engineer working for the cladding manufacturer, contractors, or the project’s architects will typically perform the design of the attachment solution. Many manufacturers produce pre-engineered and designed cladding support systems by utilizing load tables.

It is crucial for the cladding support and solutions designer to understand the requirements of the demanding project, including thermal needs. This is for designing a system and spacing of supports to be optimized for making the best use of the exterior cladding or insulation. There are various options available that will be selected equivalent to the number of factors as discussed earlier.

One of these solutions that designers choose is the discrete clip and rail type cladding support that features semi-rigid insulation placed between pin supports inboard and the continuous vertical rail. The cladding is attached to the back section of the vertical rails on the exterior side of the insulation. Another one is called a long screw, which is screwed through the rigid insulation with continuous vertical strapping. This creates a truss cladding solution system. The masonry ties are also expected, which are appropriate for semi-rigid insulations. The connection provides lateral resistance without supporting gravity loads.

To know more about cladding attachment solutions, continue reading the second part of this article.