ThermaClad is an engineered EWI system, comprising either pre-rendered XPS or Mineral wool boards, mechanically fixed to the substrate, and designed to create a defined drainage cavity. The boards are designed to be overlapping and are a final render coat ready solution. The addition of the drainage cavity allows any condensation/moisture to escape, ensuring that many of the unintended consequences associated with application of insulation, either internally or externally, on buildings can be eliminated.

Unlike many EWI systems ThermaClad uses a mechanical fixing to hold and support the non-structural insulative layer, without applying any compressive force to the insulation, while also providing a thermal decoupling to the concrete or masonry substrate. The ThermaClad unique fixing system provides the ability to create a cavity between the insulation and the existing substrate, while also eliminating any undulations that may exist.

The pre-rendered boards are manufactured with a 50mm half lap joint on all sides, which when glued together and mechanically fixed to the substrate, create a monolithic structure which has greater strength and durability than traditional EWI systems, and is weather tight before the application of the final render coat.

The final render coat is applied via specialised spray equipment that ensure a continuous and even application of the protective coat. ThermaClad has been specially designed to work in conjunction with the Properla range of super hydrophobic coatings.

Where planning or aesthetic considerations prevent the application of an EWI solution, GreyFrame can design a composite solution of ThermaClad EWI and Properla coatings to achieve the Clients design and performance goals.

The ThermaClad EWI system includes a kit of labour saving accessories, which solve many of the on-site difficulties presented by the heterogeneity of construction facades and ensures that risks associated with on-site unapproved amendments are eliminated. These accessories include a 10mm high performance insulation board (R Value 0.714, Lamada value of 0.014) designed to deliver the equivalent U value performance associated with standard 100mm insulative materials. These are used at door and window reveals where the existing frames prevent the addition of traditional insulative materials.

Where fire is a consideration for the property, the addition of a Firebreather cavity barrier at each floor level can be easily incorporated with the system.

Design Objectives and Principles:

  • Design optimised for Manufacture and Assembly (DfMA)
  • Pre-rendered insulation layer reduces site tasks and eliminates risks typically associated installation errors and inclement weather
  • Reduced reliance on skilled labour at site level, as system is a “kit of parts” – including integrated corner units, external pipe covers, starter rails, and high performance “thin” insulation for reveal areas.
  • The Grenfell tragedy brought a new focus on cladding products and issues arising from a less than robust certification process. The Hackitt report highlighted the glaring deficiencies in the testing and certification system and has ensured that specifiers are rightly more cautious. To ensure compliance with fire regulations, GreyFrame added the unique “Firebreather” cavity barrier to its suite of products.
  • Addition of high performance “aerogel” type insulative layers to reveals and heads, solves the ongoing practical issue of a lack of reveal/window frame depth.
Key Performance Criteria: XPS (Multiboard) Fireboard
Behaviour in relation to fire Class E Class A1
Strength and Stability
Thermal Performance – U value 0.15-0.30 0.15-0.30
Condensation Cavity Cavity

ThermaClad Brochure
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