What thickness of SIP panels should I use?

Optimising Structural Insulated Panel (SIP) Performance with the Right Thickness

At Formance, our Structural Insulated Panel (SIP) system is designed to deliver high-performance, energy-efficient buildings across New Zealand. With years of experience and a proven track record in both residential and commercial construction, we’ve refined our panel thicknesses to provide optimal insulation, structural strength, and ease of installation. This guide outlines how to select the best SIP thickness for different applications, ensuring compliance with the New Zealand Building Code H1.

Wall Panels: 115mm or 165mm – Choosing the Best SIP for Walls

Wall panels form the structural backbone of a SIP building system and are typically either 115mm or 165mm thick. The choice depends on insulation requirements, practicality, and integration with standard construction methods.

  • 115mm SIP Wall Panels: The most common choice, offering R2.8 (Standard EPS) or R3.3 (Graphite EPS) insulation. This thickness integrates well with 90mm bottom plate timber, making installation seamless while maintaining excellent thermal performance.

  • 165mm SIP Wall Panels: Used where higher insulation is required, achieving R4.3 (Standard EPS) or R4.9 (Graphite EPS). This is preferred in colder climates or for projects targeting energy-efficient home designs.

  • Thicker SIP Wall Panels (215mm+): While uncommon for wall applications, thicker SIPs can be used to span greater distances, reducing the need for additional structural supports.

With Formance SIPs, wall thickness can be optimised based on compliance pathways, whether using the Schedule, Calculation, or Modelling method under NZ Building Code H1.

Roof Panels: 165mm to 315mm – SIP Roof Insulation & Span Requirements

SIP Roof Panels require higher insulation levels due to exposure to heat loss and solar gain. They must also provide structural integrity over larger spans.

  • 165mm SIP Roof Panels: Suitable for smaller spans or where roof structures provide additional support.

  • 215mm SIP Roof Panels: A balance between insulation performance (R5.7 Standard EPS / R6.6 Graphite EPS) and spanning capability.

  • 265mm & 315mm SIP Roof Panels: Recommended for large spans and maximum insulation, particularly in colder climate zones or high-performance Passive House builds.

Formance SIP Roof Panels contribute to airtight, thermally efficient homes that exceed New Zealand Building Code standards.

Ceiling Panels: 165mm or 215mm – SIPs for Flat Ceilings Under Trusses

Ceiling panels are used beneath trusses to create a flat, highly insulated ceiling system. These SIPs enhance thermal performance while integrating seamlessly into a SIP construction system.

  • 165mm SIP Ceiling Panels: Suitable for standard ceiling applications where trusses provide structural support.

  • 215mm SIP Ceiling Panels: Used where additional insulation is required to meet or exceed NZ Building Code H1 compliance.

Floor Panels: 175mm or 225mm – Insulated SIP Floor Systems

Formance SIP Floor Panels offer superior insulation and structural performance compared to traditional flooring systems. They prevent heat loss in elevated or suspended floors.

  • 175mm SIP Floor Panels: Suitable for standard floor spans, providing R4.3 (Standard EPS) or R4.9 (Graphite EPS).

  • 225mm SIP Floor Panels: Used where additional strength or insulation is needed (R5.7 Standard EPS / R6.6 Graphite EPS), particularly in colder climates.

Why Choose Formance SIPs? Proven Performance & System Integration

Formance Structural Insulated Panels are engineered for efficiency and simplicity in construction. Our panel system provides:

  • High thermal performance to reduce energy costs.

  • Structural strength that eliminates the need for conventional framing.

  • Fast installation with prefabricated panels for quicker build times.

  • A proven track record in New Zealand’s toughest climates.

By choosing the right SIP thickness, builders and designers can achieve superior energy efficiency, durability, and comfort while ensuring compliance with the NZ Building Code.

Get Expert Advice on Formance SIP Selection

For expert guidance on selecting the right Formance SIPs for your project, contact our team today to discuss your building requirements.

 

Posted 9 days ago by Corban Faulkner