Which Insulation Should Be Used
Insulation and ventilation is a major step towards energy efficiency in a new house and, considering the cost of the new home today, it is relatively inexpensive.
There are many different types of insulations on the market which can be used in houses. However, not all insulations are suitable for all applications.
When choosing an insulation it is important to check the following points:
- Is it an appropriate choice for the application?
- Can the insulation provide an adequate R-value for both summer and
- Is the insulation a cost effective choice for the R-value required?
- Will the insulation fit into the space available?
- Is the insulation made to an Australian Standard? If not, has the
manufacturer satisfied you that the product is of a suitable quality?
- Does the insulation comply with the fire safety test, Australian Standard
- If being installed by a contractor, will they guarantee to install the
insulation to Australian Standard AS 3999?
Despite the relative minor cost to and enormous benefit, many builders do not routinely use insulation. As a result, their clients' end up with houses that are less cost efficient and less comfortable.
The main aim of insulation is to keep the home comfortable, warmer in winter and cooler in summer.
Up to 60% of household energy bills can be saved by installing ceiling and wall batts – think of the effect on greenhouse gases this can have. This is achieved by the ability of the glasswool, polyester or woolblend products to reduce the passage of heat.
All these products are available in a range of R-values. The R-rating is a measure of the batt's resistance to the flow of heat, therefore the higher the R-value, the greater the thermal efficiency of the product.
If you are in doubt about the R-value for your region you can make reference to the Australian Standard AS2627. This Standard actually specifies which R-values are needed for certain areas of Australia depending on the climate, type of home and heating/cooling type.
Another important consideration when insulating is the type of construction you decide to use as this can influence the R-value of the ceiling or the walls. If lightweight building materials are used you will need to increase the R-values of the insulation material in order to achieve optimum results.
Reflective foil insulation can act as a barrier against condensation when used in conjunction with bulk insulation under metal roof. This is achieved by preventing the vapour of the internal humid air from coming into contact with the cold metal roof.
When to install insulation?
It is easy for builders to adopt the attitude that if clients want insulation, they can buy it themselves later. Conversely, some new homeowners or renovators may feel the builder is trying to string them along with an extra gimmick.
The fact is, walls and some roof/ceiling types can be extremely difficult and very expensive to insulate after construction. Hence, always insulate during construction. As ceilings may then only be accessible to insulate after construction is completed.
Armed with the knowledge of 60% energy savings, greenhouse gas reductions, reduced internal noise and condensation control, overcomes any suggestion of a gimmick.
Except in Victoria and the ACT (where insulation is mandatory in new construction), builders mistakenly view insulation as a high cost, luxury product that is not really necessary. As a result, many are loathe to broach the subject with their clients.
Insulating the ceiling of an average 12 square home would cost approximately $550 (DIY) or you can have them installed by an authorised Insulco installer for a small-added cost. Hardly an extravagant cost when you consider the benefits and potential savings over the life span of the house.
An important tip when selecting insulation is to select the proper R-value, and the right product for the application. Are you attempting to achieve acoustic and thermal properties, or just one of these properties. Also make sure a recognised authority has carried out the testing of the products, to the specified R-values. Remember the higher the R-Rating of the bulk insulation, the greater its thermal performance.