Thermally Broken Cladding Attachment Systems



Rain screens provide virtually limitless design options for building façades while controlling moisture and reducing energy consumption. Knight Wall Systems manufactures versatile, ventilated rain screen façade attachment systems that accommodate a wide array of cladding options. Knight offers several attachment solutions and multiple rails for different insulation assemblies: the award-winning CI-System and HCI-System, which pair a drop-in facade attachment with rigid exterior foam insulation, enabling ASHRAE 90.1-compliant continuous insulation; and the ultra-sustainable MFI-System rain screen, which utilizes mineral fiber insulation. Knight prides itself on having inventory of all standard rain screen components in stock at all times, ensuring short lead times.

Direct Fasten (Claddings <9lbs/sf)
Over Rigid Insulation
(Mineral Wool or Foam Plastic) 

Direct Fasten (Claddings >9lbs/sf)
Over Rigid Insulation
(Mineral Wool or Foam Plastic) 


Knight HCI System


Knight CI System


Thermally Broken (Claddings <5lbs/sf)
(With Mineral Wool Insulation)

Thermally Broken (Claddings >5lbs/sf)
(With Mineral Wool Insulation)

Knight ThermaZee System Knight MFI System

Industry Insights

The Code Requirement: (per IECC 2018 Tables C402.1.3 & C402.1.4)

The minimum prescriptive R-Value Method (Table C402.1.3) requirements of the energy code for Climate Zones 5 & 6 requires Continuous Insulation (ci) for almost all above grade opaque wall types.  Assembly U-Factors must now be calculated using a corrected R-Value for steel stud wall assemblies, effectively requiring continuous insulation in the assembly to meet the required assembly U-Factor.

The Definition: (per IECC 2015 and ASHRAE Standard 90.1-2016 & IECC 2018)

Continuous Insulation (ci): Insulation that is continuous across all structural members without thermal bridges other than fasteners and service openings. 

The Challenge:

The thermal performance requirements of our building enclosures has increased significantly in the last 20 years. Increased performance requirements have outpaced readily available and understood solutions.  As a result, the actual thermal resistance of many opaque wall systems currently used does not achieve its intended thermal performance and sometimes does not even meet the minimum requirements of the energy code.   Many commonly used opaque wall systems achieve only 40-80% of their nominally rated thermal performance.

The Solution:

Engineered, thermally broken cladding attachment systems can support meeting the definition of Continuous Insulation and can provide up to 98% thermal effectiveness for continuous insulation solutions.


Click here for NFPA 285 & IECC compliant wall assembly Basis of Designs (BODs) for Climate Zones 5 & 6

Additional Resources:

Morrison Hershfield

Z Girt Thermal Short Whitepaper

Morrison Hershfield


Knight Wall Systems

Thermal Performance Comparison

Meeting the Energy Code

With Mineral Fiber Insulation




Payette Research

Thermal Performance of Facades

BC Hydro

Thermal Performance of Facades


Thermal Bridging Solutions 


KWS HCI Air & Thermal Testing