What is sarking?

Sarking is a layer of flexible insulation typically installed under roof tiles when a home is being constructed.  It consists of aluminum foil laminated onto paper or plastic backing with a flame retardant adhesive and fibreglass reinforcing mesh, and is manufactured in sheet form.    Sarking performs a dual function, helping to keep your home insulated from the heat of summer whilst retaining warmth in the winter.  This thermal lining is a very cost effective means of insulating a home.  The use of sarking can be mandatory or discretionary depending on a variety of local criteria including requirements for bushfire prone areas, wind speed and the specific construction specifications of your roof.

Benefits of sarking

Foils are a versatile material for use in building applications, as they provide:

• high thermal reflectivity
• water-resistance
• weather proofing
• dust reduction
• fire retardancy
• lightweight
• non-toxic

What to look for?

When purchasing sarking or contracting a builder to install insulation in your home, ensure the product meets the following criteria:

• complies with the requirements of the Building Code of Australia (BCA), specifically relating to pliable building membranes (AS/NZS 4200.1.)
• BCA standards state sarking must have a flammability index not greater than 5
• make sure your insulation product complies with local building authority requirements

What is insulation?

Insulation comes in a variety of materials all utilised for their thermal resistance.  They are typically installed in the ceiling/roof, floors or walls of a home, and act as a buffer against heat loss during winter, whilst slowing the heat transfer from the walls or roof into the living areas in summer.  Choosing appropriate insulation is one of the most cost-effective ways of improving the comfort and energy efficiency of your home. The effectiveness of insulation is evaluated by its r-value, so look out for this when purchasing a product or consulting a supplier.  The r-value refers to the thermal resistance of the product, and often correlates to the thickness of the material.  R-values range from between 1 and 4, with a higher figure indicating a greater heat resistance, and therefore energy efficiency.

Benefits of insulation

Insulating your home can:

• curb green house gas emissions by reducing the use of non-renewable energy resources
• save money on energy costs - heating/cooling systems in the home will operate more efficiently
• enhanced comfort - warm in winter, cool in summer
• add value to your home - increase its marketability
• improve fire safety - by eliminating air leakage in your roofing

If you need advice on any aspects relating to the insulation of your home contact a reputable builder or installer.