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The Basics of Thermoseal Roof Sarking for Your Reroofing Projects

16 December 2021

Roof sarking is a protective second skin under your roof, installed when building a house, doing home extensions, a home renovation or roof restoration. Roof sarking is a pliable laminated membrane placed under your roof during installation by the builder. It is rolled out in sections in parallel or perpendicular to the eaves, with an overlap between each layer.

Roof sarking will protect the frame of your house from the weather during construction. When your home is completed, sarking will protect your roof cavity from storm-driven rain and dust. It will also improve its thermal performance, help it resist bushfire ember attacks and reduce the risk of harmful condensation.

Thermoseal reflective foil roof sarking is a non-permeable, vapour barrier product designed to reduce the transmission of moisture into the home and contribute a reflective air gap R-Value to the roof system when positioned adjacent to an inward or outward-facing air cavity.

How Thermoseal Roof Sarking Works

Thermoseal Roof Sarking is like a safety blanket for your house. A simple way to understand how reflective foil laminate membranes like Thermoseal work, is to compare them to a survival blanket. The silver foil blanket helps regulate temperature, whilst at the same time protecting from hot or cold weather, particularly where additional protection from wind and rain is also required.

Likewise, reflective foil sarking products can shield up to 95% of radiant heat away from the roof cavity space. Thermoseal works under your roof tiles, like a protective second skin, helping make your home more comfortable and protecting the things you value from the weather.

What’s So Good About Roof Sarking?

Your home will feel more comfortable and you will feel assured knowing that sarking can protect the things you value when you need it most.

How Roof Sarking Helps To Protect Your Home Once It Is Completed

Roof sarking improves thermal performance by shielding the home from up to 97% of radiant heat when combined with an air space, helping to provide a more energy-efficient and comfortable home. Vapour permeable sarking reduces the risk of condensation formation, by allowing water vapour to be effectively managed and safely drained away.

All sarking helps protect your home from unseen mould growth or even worse, ceiling staining or permanent damage. This can result from the entry of storm-driven rain into the roof cavity. It also limits dust entering the home through gaps around downlights and vents by reducing draughts that blow dust into the roof space.

Roof sarking is mandatory in all BAL 12.5 to 40 rated areas to meet the bush fire ember attack requirements by Australian Standard 3959. It provides a secondary form of ember protection for the roof space.

Visual Deterioration: Deflection or staining of plasterboard linings as a result of moisture trapped behind the linings can cause ugly stains and swelling of standard plasterboard

Structural Decay: Moisture trapped within the structure can result in long term corrosion of metal structures, timber rot, loosening of nails as timber swells, and cladding rot or swelling that can result in costly rectification work.

Energy Efficiency: A reduction in the buildings energy efficiency can occur due to moisture saturation of the insulation, resulting in loss of thermal performance.