Heavy insulation: The most important component of a passive house is a layer of highly efficient insulation
that wraps continuously around the building envelope -- even beneath the concrete slab in the basement --
reducing heat transfer between indoor and outdoor spaces.
For passive houses in New Zealand - and elsewhere, this primary component of highly efficient insulation all over and around, is constructed of durable and strong material of known heat transfer characteristics which can be used in the computer model which is used to quantify and assess the final building quality and whether or not it meets passiv-haus standards.
Straw-bale house ideals are in part incorporated in Passive House design, but along with other components the passive house design is a more complete package incorporating energy conservation, heat retention in winter, and supply of filtered clean air which is pre-treated to near the temperature of the expelled air.
This excellent insulation is so good that, combined with the other components of a passive house such as heat recovery from exchanged air, even in a very cold climate such as the Austrian Alps, the heat given off from the human bodies actually provides much of the required heating. That is, left-over energy from the food eaten by the inhabitants, calculated at about 70 watts per person, is enough. Some scientists report that 100 watts heat energy is emitted per person.
See this paper from Germany which gives some idea of the benefits.
In this way, the amount of energy needed to be purchased for heating is greatly reduced. In addition, it is much easier to maintain house internal temperatures at healthy levels, as compared with many older New Zealand homes which notoriously run in winter at temperatures so low, that, as many health studies have shown increased sickness and mortality of older people and the very young result.
In passive houses the whole house (not just those rooms being occupied for the moment) has its heat level maintained at the saome temperature, and clean air is likewise supplied throughout.
Passive houses result in healthier families than other kinds of house design do.
A passive house in New Zealand could not use a normal [ as at 2011 ] log-fire because the heat output is too great. Smaller fires can be imported. Likewise, a normal heat pump could be useful to provide initial warmth for a house in winter if it has been vacant for a while, but after that it would not be needed. The left-over heat in the air arising from cooking, showering, refrigerators and human bodies, extracted from the exchanged air by the air-supply system, will mostly be enough to provide a very comfortable living temperature.
Would you like to see a passive house in New Zealand now?
You can follow the blog of the first build at
New Zealand's first Passive house blog-spot
Another NZ passive-house is documented on-line, on facebook. If you are a facebook user, you should have no problems viewing these pages.
A New Zealand Passive house set of informative pages
A New Zealand Passive house - the base page
Congratulations to Brooke the Architect (MOAA Architects) for what looks like a thorough job, and likewise the builder for following instructions so well. Lots of construction detail in here.
Links to pages about the seven precepts of Passive House design.
Very efficient Insulation
No thermal bridges
Passive solar gain
Prices / costs