Insulation products

Prices are per m² and inclusive of GST. They’re supplied by the manufacturer or distributor and indicative only. Installation costs may be additional.

POA stands for “price on application”. Some manufacturers don’t supply estimates of price per m² for their products, so you may have to ask in-store. A few of these products can only be installed by specialists, so installation cost is tied up with product cost – these specialists should usually provide free quotes.

Before spending money on insulation, sort out draughts.

Seal around doors and windows, block off unused chimneys and remove downlights that are not rated 'close abutted' (downlights with air gaps around them).

But remember you will still need to air or ventilate the house to prevent damp accumulating and to maintain air quality. Even on the coldest nights you will need some fresh air in the house. There is a fine line between draughts and ventilation.

You may be eligible for help (see below) to fund insulation improvements.

If you are unsure about how best to insulate your house, consider paying for a home energy rating. For background information see www.energywise.govt.nz.

You will receive an independent assessment of the energy performance of your home including how well the building's design, construction and orientation enables it to maintain a comfortable indoor temperature, and how efficient the indoor heating and water heating are. You will get recommendations for the most cost-effective ways to improve the house's energy efficiency and reduce your energy costs.

Free insulation

Warm Up New Zealand: Healthy Homes projects provide free ceiling and underfloor insulation for low-income households occupied by people with health needs related to cold, damp housing. Availability is through regional projects.

Home owners or tenants may be eligible if they have a Community Services Card and the house is occupied by someone under 17 years or over 65 years. People can also be referred to the programme by a health provider if they are at risk from illness linked to cold, damp housing - such as a respiratory condition.

Visit www.energywise.govt.nz for terms and conditions and more information.

The World Health Organisation recommends indoor temperatures of 18-24°C for healthy living. Cold and damp living conditions affect the health of many people and can worsen the symptoms of illnesses such as asthma, bronchitis and other breathing disorders. Damp also encourages the spread of dust mites which can further worsen these disorders.

Damp insulation within the wall framing dramatically reduces the insulation value, making rooms harder to heat. The combination of cold damp rooms and the presence of some fungi will worsen respiratory problems for the very young and very old.

If the space under the flooring is damp, then it is likely fungi will grow on the underside of timber flooring as well as infiltrating the flooring into the house.

Some fungi which grow within wet wall cavities and under floor boards are toxic. In particular the stachybotrys mould (a type of fungi) produces spores which carry chemical toxins known as mycotoxins. These may cause flu like symptoms. They particularly affect the young, the old and those with weakened immune systems.

Stachybotrys can be present within a damp wall cavity or on the underside of the floor boards with no obvious signs or ill effects, but once exposed or disturbed they will produce airborne spores which can be inhaled by those in close proximity

If stachybotrys is found, you will probably need to leave the home while repairs are made. People working on the removal of affected timber have to wear protective gear.