Roof sarking improves comfort, saves energy, and shields from severe weather elements. This guide explains what roof sarking is, when you need it, how to pick the right one, plus tips for installing it and good products that Aussie builders trust.
What Is Roof Sarking?
Roof sarking is a flexible soft membrane that goes under your roof. Often found beneath metal or tile roofs, it adds extra safety, keeping your house safe from:
- Dust and debris
- Wind draughts
- Moisture and rain ingress
- Radiant heat from the sun
Most new sarking products have reflective foil that helps reflect heat away from your roof space. This makes your home stay warm in winter and cool in summer.
Is Roof Sarking an Insulation?
Roof sarking is a type of reflective insulation. It reflects heat instead of blocking it like batts or foam. It helps keep your roof and attic space cooler.
Alone, sarking may not meet rules for keeping homes warm in Australia. It works best as one part of a layered insulation system. It helps boost the R-value of your roof when combined with bulk insulation.
Best Roof Sarking Products in Australia
Sisalation® Metal Roof Sarking
Heavy-duty sarking designed specifically for metal roofs.
- Type: Reinforced reflective foil laminate (RFL)
- Best For: Residential and commercial metal roofing
- Strong moisture barrier
- Reflects up to 95% radiant heat
- Provides a secondary weather shield during construction
- Suitable for BAL-rated bushfire zones (up to BAL-40)
- Reduces dust ingress and wind draughts
- Compliance: Meets NCC 2022 and AS/NZS 4200.1 standards
✅ Ideal for harsh weather zones and bushfire-prone areas
Sisalation® Vapawrap® Metal Roof
High-performance vapour permeable membrane for metal roofs.
- Type: Vapour-permeable, triple-layer construction
- Best For: Homes where condensation control is essential
- Allows moisture vapour to escape, reducing condensation risks
- Water-resistant — protects during and after installation
- Helps improve air-tightness and energy efficiency
- UV-resistant for up to 3 months exposure
- Soft, flexible material for easy handling and installation
- Compliance: AS/NZS 4200.1 certified
✅ Great for cool climates or homes with mechanical ventilation where condensation is a concern
Sisalation® Multipurpose Foil
Versatile foil insulation for walls, roofs, and industrial applications.
- Type: Double-sided reflective foil laminate
- Best For: Multipurpose applications — roof sarking, wall wrap, underfloor insulation
- Reflects radiant heat — helps reduce energy bills
- Reinforced for tear resistance during install
- Lightweight, flexible, and easy to cut
- Water barrier and dust seal
- Can be used in non-habitable spaces (e.g., sheds, garages)
- Compliance: Meets AS/NZS 4200.1 standards
✅ Ideal for builders or DIYers needing a budget-friendly, flexible solution
Is Roof Sarking Required by Law in Australia?
It depends on your location and building conditions. According to the National Construction Code (NCC), roof sarking may be mandatory in the following scenarios:
- In bushfire-prone areas, as part of BAL (Bushfire Attack Level) compliance
- In areas with strong wind ratings
- Where roof pitch and design make water runoff critical
- For new builds, to meet energy efficiency and building envelope standards
Even where not required, sarking is strongly recommended for long-term comfort, efficiency, and structural protection.
Roof Sarking Installation Guide
How to Install Sarking Under a Metal Roof
- Start at the eaves and work upward toward the ridge
- Overlap sheets to guide water away from the structure
- Secure with battens or purlins to avoid sagging
- Leave an air gap between sarking and metal roofing
- Tape all joins with reflective foil tape to prevent leaks
- Fix using staples or fixing pins — avoid punctures
Installing Sarking Under Tiled Roofs
- Roll foil directly onto rafters
- Overlap and tape seams
- Install roof battens over sarking to support the tiles
- Ensure overlaps shed water downward
Buy Roof Sarking Online or Get Expert Advice
If you’re building or renovating in Australia, roof sarking is one of the smartest investments you can make. It helps with insulation, makes your home use less energy, and strengthens the weather resistance of your roof.
If you are unsure which option is best for your project, our team can help. We provide sarking product suggestions and installation advice. Reach out today via email or call us on 1300050513 for friendly, expert advice.