Structural insulated panels (SIPs): structural principles and design

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Structural insulated panels (SIPs) are composite engineered products consisting of two high density facings, typically orientated strand board (OSB), which are bonded on both sides of a low density, cellular foam core. These prefabricated, high performance, lightweight building panels can be used in walls and roofs for residential and commercial buildings.


SIPs offer a good thermal and airtightness performance for structural applications where minimal thermal bridging is required. They are manufactured under closely controlled factory conditions and can be custom designed for each application. The result is a building system that is extremely strong, energy efficient and cost effective.


This Wood Information Sheet includes TRADA's advice on:

  • structural and general erection principles
  • fire performance - design and construction
  • building modification, extension and repurposing.


This WIS was revised in June 2020 to reflect changes to Building Regulations in relation to fire safety.


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