Insulation - it's a big saver

Most of us don't think about insulation, our ceilings or roofs. Why would we? We think of our roof as a means of protecting us from the elements. Yet most of us will be surprised to discover that our roof and ceiling plays an important role in household temperature regulation. Most heat transfer is through the ceiling and roof.

In your home heat travels upwards, which means that the highest percentage of heat transfer occurs via the roof and ceiling. In fact, an uninsulated ceiling could lose up to 35% of heat in winter and gain up to 35% of heat in summer.

Insulating a home is the simplest, most effective and cheapest way to make a house more energy efficient. By installing insulation you can keep your house cooler in summer and warmer in winter and can help you save up to 40% in heating and cooling bills. That's a huge saving.

Ideally the best time to install insulation is during construction. However insulation can be added to existing buildings with a little planning and effort.

Ceilings with easy access are relatively simple to insulate post-construction. Note that some types of roofs, such as skillion roofs can be difficult to insulate post-construction, as the internal or external lining must be removed.

If you're thinking about ceiling insulation have a quick look at the information below. We've tried to simplify the mass of information in the market to help you decide what best suits your needs. And if you've already decided what you want, but are interested in details of government rebates and the savings you can make, just click here.

What types of insulation are available?

The best type of insulation for your home depends upon where you live and whether you need to keep heat in, out or both. Your home's design, orientation and materials are also factors.

There are many types of ceiling insulation products on the market today. These products come in two main categories – bulk and reflective. Here's some information to help you decide what will suit you best:

1. Bulk insulation

Bulk insulation helps keep heat in or out by stopping heat from entering or escaping. Bulk insulation is available as batts, blankets and boards, or as loose fill which is pumped, blown or placed by hand into the area to be insulated.

Bulk insulation has a material R-Value*, the higher the R-Value the more resistant the insulation is to heat flowing in and out of the home and the greater the thermal performance.

Materials for bulk insulation include:

  • Glasswool (fibreglass)

    Made from melted glass spun into a flexible mat of fine fibres. This is available as batts or blankets. Blankets are thinner and denser than batts, and are available with reflective foil attached to one side.

  • Natural Wool

    Made from sheep's wool formed into batts, blankets and loose-fill. Most batts and blankets are made of a wool-polyester blend to reduce settling and compression. Wool is naturally flame-resistant, however, the addition of synthetic fibres increases flammability – check with supplier for fire resistance testing results. Wool must be treated to be moth-proof.

  • Rockwool

    Made from volcanic rock melted at high temperatures and spun into a mat of fine fibres.It's available as batts or blankets, but is denser than glasswool, so R value* per unit thickness is higher. This type of material has better sound absorption qualities than glasswool, but it's more expensive.

  • Granulated rockwool

    A loose-fill form of rockwool which is pumped, blown or placed by hand into the area to be insulated.

  • Cellulose fibre

    Made from waste paper pulverised into a fine fluff. This type of insulation is cheaper to purchase and install than other types of bulk insulation. However it must be treated with fire retardant chemicals to reduce flammability.

  • Polyester

    Made from polyester fibres (including recycled PET bottles) spun into a flexible mat, and is available as batts or blankets. Does not burn, but will melt if exposed to a direct flame at high temperatures.

2. Reflective insulation

Reflective insulation is usually a shiny aluminium foil laminated onto paper or plastic (also known as reflective foil laminates or RFL) and is available as sheets (sarking), concertina-type batts and multi-cell batts. This type of insulation helps to keep your home cool in summer by deflecting radiant heat.

Materials for reflective insulation include:

  • Reflective foil laminate

    Reflective foil laminate – is foil laminated to paper with glass fibre reinforcement. It's typically used as roof sarking and wall insulation. Double-sided foil is more effective than single-sided, provided that both sides face a still air space; it is also more water resistant. However, double-sided foil is typically produced with an anti-glare coating and this will reduce the insulation's effectiveness by around 10%.

  • Multi-cell reflective foil products

    2, 3 or 4 layers of laminated foil separated by partitioning to provide a 1,2 or 3 layered cell structure. Can be installed over ceiling joists and between or across wall studs.

  • Foil bonded to bulk insulation

    Foil bonded to bulk insulation – is reflective foil bonded to batts, blankets or polystyrene boards and will increase insulation benefits if installed with the foil facing a still air space. This type of blanket is a common method of insulating cathedral ceilings and under flat roofs.

Other benefits of installing insulation

Although insulation is designed to act as a barrier to heat flow and is essential to keep your home warm in winter and cool in summer, it can also assist with weatherproofing and eliminating moisture problems such as condensation. Some types of insulation also assist with soundproofing.

For professional advice on the supply and installation of ceiling insulation click here to go to the Together Today Eco Directory.

How to Keep Saving

The State Government is offering rebates for the purchase and installation of ceiling insulation. For details of this rebate simply click here.

To help Australian families with the cost of installing water saving and energy efficient products the Commonwealth Government is offering interest free Green Loans of up to $10,000. A Green Loan does not affect or make you ineligible for any available Government Rebates. To find out more about Green Loans click here.

*Please refer to the Together Today Glossary for more details

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