Thermal insulation is made up of very thin glass fibres that are matted together to form millions of air pockets. These air pockets are very poor conductors of heat and resist the flow of air or radiation into or out of your home.
This ‘resistance’ is known as the R-value. R-values are the measuring tool we use to rate the level of thermal resistance. The higher the R-value the better the thermal performance it will provide. It is important that you understand what R-values mean because they can result in you getting the best product for your home. Understanding R-values will help you compare the different products that are out there in the market.
- Material R-values are supplied with bulk insulation (such as Bradford Gold insulation batts) and refer to the insulating value of the product itself.
- Total R-values are supplied with reflective insulation (such as Bradford Thermoseal roof sarking products) and depend on the product being installed as specified. R-values can differ depending on the direction of heat flow through the product, more so in reflective insulation rather than bulk.
- ‘Up’ R-values describe resistance to heat flow upwards (sometimes known as ‘winter’ R-values).
- ‘Down’ R-values describe resistance to heat flow downwards (sometimes known as ‘summer’ R-values).
All new homes being built in Australia have certain energy efficiency levels they must meet as required by their state. By taking into account the R-values of the product this will help you comply with what your state requires.
It is more cost effective to build insulation measures in at the time of construction, especially with wall insulation as it is costly to remove your plasterboard to add insulation at a later date.
Improve energy efficiency with wall wrap
Reflective foil wall wrap provides a layer of thermal insulation and acts as a protective second skin, safely draining away any unintended water leaks in the external cladding. Yet wall wrap also performs another, very important function behind the exterior of your home by reducing air infiltration and draughts in the building cavity, which helps to improve the energy efficiency of the wall system.
In 2013, the Building Science Corporation published data proving that the heat transfer properties of all types of insulated walls (without wall wrap), were reduced by air movement through the structure. On average, a typically constructed wall will transfer 12% more energy in winter and summer than a well-air-sealed wall. When wind is taken into account, 31% more energy will be transferred in winter and 26% more energy in summer.
This can be easily rectified at the time of construction by incorporating a well installed wall wrap as an air barrier membrane within construction system. Not only will this improve the efficiency of the bulk insulation in the wall, outward facing reflective wall wraps can also further boost the performance of the insulation by up to RT0.5 to create a higher performing wall system.
Incorporation of wall wrap during construction can also assist in improving construction times by allowing internal trades to commence work earlier, particularly during periods of rain. For more information on wall wrap and its benefits, check out the wall wrap page.