Insulation is one of the best things you can do to make a house warmer and more comfortable to live in and you should think of that before heating, says Christian Hoerning, the Energy Efficiency and Conservation Authority's senior technical adviser, buildings.
New houses typically come with double glazing and must have insulation but Hoerning suggests exceeding the requirements. "Installing insulation really well in existing houses is one of the best things you can do. If a home has no insulation then ceiling and floor insulation can halve the heat loss. If there is an accessible roof space it can be retrofitted fairly easily. It needs to be about 400 millimetres thick."
The Government's Heat Smart scheme to subsidise the insulation of ceilings and floors of houses built before 2000 began in July 2009 and Hoerning anticipates 230,000 will have taken advantage of it by September, when the programme ends. It will be followed by a new, yet to be finalised, scheme targeted at low income households.
(The apparent success of the New Zealand scheme compares favourably with Australia's subsidised insulation scheme which crumbled under the weight of shoddy workmanship, several deaths, house fires from incorrectly installed ceiling insulation and rorting.)
Hoerning says ceiling and underfloor insulation typically cost $3000. The subsidy is 33 per cent, up to $1300, and the balance can be paid off through the homeowner's rates or mortgage. Installers must install products approved for use under the programme and the installation must meet quality standards.
Hoerning recommends that people retrofitting with insulation should consider an installer trained to Eeca standards. There is not, he says, a big difference in the cost of getting a professional or the material from the hardware shop.
There are, he says, many products in rolls or pieces and also loose fill which can be blown into ceilings, but it has variable performance and needs a gap above older recessed down-lights or metal flues. New down-lights must be able to be abutted to insulation. The authority favours bulk insulating products for ceilings, pre-cut to fit between joists, or blanket-like rolls of insulation made of fibreglass, polyester or wool, fitted over the whole ceiling.
For underfloor, there are bulk insulation products made of polyester, wool and polystyrene.
Foil, says Hoerning, can rip and is hard to install so it performs well. It should only be left if it is in perfect condition.
Insulation is cheaper if installed do-it-yourself style. At Mitre 10 Mega, Pink Batts fibreglass baling enough for a modest ceiling costs about $1120 and an underfloor version with a moisture barrier slightly less than $1000. Enough Xpol, rigid polystyrene, for a modest underfloor costs about $1000.
HEAT ON A BUDGET
Haven't got the earth to spend on heating? Here's what adviser Paul Doocey would spend given limited budgets. He emphasises that any outlay can be wasted in a damp house. "Start with the things that make the most difference. Reduce dampness and increase insulation before putting heat in place."
■ An extractor fan, for $50 to $70, for the kitchen, to reduce cooking moisture, or one for the bathroom to get rid of steam from the shower. The necessary electrician to install it is extra cost.
■ A small electric heater - sometimes a flatter's only option.
■ Cheap draught-stoppers to roll against draughty doors.
■ Enough DIY plastic insulation film to attach to the frame of a lounge window or more.
■ Pounce on any decent op-shop curtains and fit them closely to reduce heat loss.
■ It costs nothing to keep a house well-ventilated by opening windows or to let the sun in during the day.
■ Buy a moisture-proof, polythene groundsheet to spread under the house to reduce the amount of moisture reaching the underfloor.
■ Take a trip to the local curtain bank or decorator exchange for good, preferably thermally backed, at least double-fabric, second-hand curtains.
■ Buy, and have installed, bathroom or kitchen extractor fans.
■ Buy an electric heater but don't be tempted by a non-flued gas heater.
■ Buy a modest dehumidifier, which will spit out heat as well as dry the air.
■ Possibly a "cheapie" heat pump, installed back-to-back, with the outside unit directly behind the inside one.
■ Possibly a lower-end woodburner.
■ Possibly ceiling or underfloor insulation, with the government subsidy.
■ Good, heavy, close-fitted curtains for a few windows, preferably with pelmets.
- Your Weekend
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