News Items

What's New

 

Major upgrade to H1 announced

Changes mandatory Nov 2022.
 
The Ministry of Business, Innovation and Employment says the new updates to minimum insulation requirements aim to reduce energy needed to heat new homes by up to 40%. “The changes go as far and as fast as is achievable using current insulation products and construction design and practices.”
 
There are now six climate zones.
 
Minimum construction R-values are significantly increased in some instances. Under the Schedule Method, the minimums are now R6.6 for the roof in all climate zones, with windows and door minimums R0.46 in the four warmest climate zones and R0.50 in the two coldest climate zones. (Skylight requirements are higher in the four colder zones.)
 
There is a 1-year transition period ending 3 November 2022, although the new window insulation requirements in the warmest climate zones have a 2-step increase. Between 3 November 2022 and 2 November 2023, the minimum construction R-value for windows and doors in climate zones 1 and 2 is R0.37. After 2 November 2023, it rises to R0.46.
 
The Schedule, Calculation and Modelling methods of demonstrating compliance still remain, but are now included In H1/AS1 (Schedule and Calculation) and H1/VM1 (Modelling) rather than in a separate standard.
 
The scope of H1/AS1 covers housing, and buildings other than housing less than 300 m2.
 
You can find the details here.

 

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Green modelling tools in H1/VM1

Single-zone tools brought in. Read more.

The 5th edition of H1/VM1, introduced on 29 November 2021 (with a 1-year implementation period) brought a significant change to the modelling method of demonstrating compliance. The modelling method now allows single-zone modelling tools, such as:

  • Passive House Institute’s PHPP (Passive House Planning Package, used for designing and certifying Passive Houses)
  • New Zealand Green Building Council’s ECCHO tool (used under Homestar).

H1/VM1 Appendix D. Modelling method – Building energy use comparison sets out the requirements. Subsection D1.6 has been revised to allow modelling software that uses a single thermal zone.

All other modelling requirements must still be met.

You can download a PDF of H1/VM1 5th edition here.

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Wood burners and air pollution

New report gives update.

A new government report confirms that wood burning for home heating is a major source of air pollution in New Zealand. Most particulate matter from wood smoke is PM2.5, which is more harmful to human health than larger particles. 

“The residential sector (primarily burning wood for home heating) contributed 30 percent of PM2.5 emissions and 41 percent of carbon monoxide emissions. Almost all particulate matter emissions generated by the residential sector were PM2.5.” 

“One New Zealand-based study found that living in a neighbourhood with a higher density of wood burners was associated with an increased risk (28 percent) of nonaccidental emergency department visits in children younger than three years old.” 

The data in the report contains both good and bad news: 

“PM2.5 concentrations at 50 percent of locations have improved since 2011. However, 95 percent of sites were higher than the 24-hour and annual 2021 WHO air quality guidelines at least once between 2017 and 2020. The sites with the highest PM2.5 concentrations were above the guideline for around a quarter of the year. These high concentrations generally occurred during the colder months.”  

The information comes from the report Our Air 2021: Final release, published in late December by the Ministry for the Environment and Stats NZ. It is the third report in a series, following reports in 2014 and 2018. 

The report compares concentrations of pollutants against New Zealand’s National Environmental Standard for Air Quality (NESAQ), the 2005 WHO air quality guidelines, and the 2021 WHO air quality guidelines (the latter being the most stringent).  

You can find the report here

 

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CLT shines in seismic testing

Engineered timber resilient.

Research funded by the Earthquake Commission has found that multi-storey walls constructed from cross-laminated timber (CLT) can be strong and resilient in earthquakes. 

The work involved testing large CLT shear walls in the University of Canterbury Structural Engineering Laboratory. Researchers loaded the walls horizontally to simulate big earthquakes like the ones experienced in Christchurch.  

The research team designed high capacity connections for the walls. They found that steel dowels in the connections bent to absorb energy and prevent the walls from being significantly damaged or collapsing. After an earthquake the dowels could just be replaced and building occupants could quickly return. 

The weight of timber is only one-fifth that of concrete, but engineered timber has similar strength as concrete. Timber also has a key role to play in New Zealand achieving a net-zero carbon economy. 

The Earthquake Commission says that the research shows that “cross-laminated timber (CLT) walls are feasible and cost-competitive with steel or concrete systems in low-rise buildings and offer significant environmental benefits.” 

You can find more details and watch a video clip here.