Home Style Green - Sustainable Design and Building (Building)

More is not always better, especially regarding the amount of timber in the frame of a house. The more timber there is, the less space there is for insulation. The way this is measured is called timber fraction.

Most homes in Aotearoa are designed using the assumption that timber will make up around 14% - 18% of the area in a wall. A 2020 BRANZ research study found that in reality, the average timber fraction is closer to 40%. This means there is considerably less space available for insulation.

Unfortunately, this is not always picked up during the consenting or pre-lining inspection process. H1 Energy Efficiency calculations are checked at the design stage, usually using the much lower default timber fraction assumption. The result of all this is that many consumers are effectively getting less insulation than they're paying for, and much more thermal bridging. 

PlaceMakers has recently launched a new service providing a detailed report of the actual timber content for any wall frame and roof truss they supply. This accurate figure can then be used to provide true H1 calculations. Alternatively, a designer might choose to adapt their plan to reduce the thermal bridging and increase the amount of insulation.

National Technical Resource Manager, Pete Hammond explains how Framology works. We also discuss the option of using external insulating products like RigidRAP-XT from IBS to eliminate thermal bridges.

Direct download: Build_Aotearoa_6__Framology_with_Pete_Hammond.MP3.mp3
Category:Building -- posted at: 11:06am NZDT

Richard Houghton now lives in a very good, healthy home. But that wasn't always the case. Along with Simon Cator from Pro Clima NZ, we discuss Richard's journey in designing and building an energy-efficient SIP home just outside Auckland, New Zealand. 

Direct download: 270_Richard_Houghton.mp3
Category:Building -- posted at: 9:57am NZDT

I wanted to have Dolores Davis on the show because she's running a company that values the art, the privilege and the responsibility of building. Here in New Zealand, the evidence that a building boom doesn't guarantee success in the industry, is all too common.

Just as we can learn building methodologies from around the world, we can also learn successful business practices so we can continue to enjoy not what we have to do, but what we get to do.

Direct download: 187_CGS_Design_Build.mp3
Category:Building -- posted at: 7:59pm NZDT

I caught up this week with Lois Easton from Beacon Pathway. Lois is one of the organisers for the 'Building a Better New Zealand' conference coming up in September. 

Submissions for abstracts is open until March 9th, so if you're interested, check out their website for more details.

http://www.buildingabetternewzealand.co.nz/

Also in this week's show:

Direct download: 57_Building_a_Better_New_Zealand_with_Lois_Easton.mp3
Category:Building -- posted at: 10:50pm NZDT

In this short, sharp episode of Home Style Green, I answer a listener question about insulating the edges of a concrete floor slab, what to do if you can't afford to install solar hot water, thermally broken windows, getting extra insulation in your walls and LED lighting. 

Direct download: 43_Concrete_slab_hot_water_windows_walls__LEDs_-_Listener_Questions.mp3
Category:Building -- posted at: 8:34pm NZDT

ZETA Design + Build produce modular buildings inside a factory. I spoke with CEO, Howard Koenig this week to talk about why anyone would want a factory built home. Turns out there are some very compelling reasons. Listen in to find out more.

Useful links:

Direct download: 39_Howard_Koenig_ZETA_modular_building.mp3
Category:Building -- posted at: 8:54pm NZDT

The New Zealand Building Code is implementation of the Building Act 2004. It's a 'performanced-based' code, but don't let the name fool you. In this epside I discuss why the Building Code can't be relied upon to produce a good home for you, and what you can do about it. 

Useful Link: 

EECA Report Investigatin quality of insulation in new build residential homes:http://www.eeca.govt.nz/node/11719

Direct download: 35_Why_You_Cant_Trust_The_Building_Code.mp3
Category:Building -- posted at: 10:44pm NZDT

Prefab, (short for prefabrication), offers significant advantages to buidling. House can be:

  • Higher quality, with improved finishing and attention to detail without deterioration from being exposed to the elements
  • Produced quickly, being assembled in a matter of days or even hours
  • Very resource efficient, producing little construction waste (a big environmental problem for the sector)
  • Affordable!

So why are we not doing more of it? 

Bell has lead PrefabNZ since it was conceived and then incorporated directly as a result of her research as part of a Masters in Architecture. She's arguably New Zealand's most expert voice in the industry and is motivated to share the many benefits and some of the challenges of prefab. 

Links

Pam's Book recommendations:

Direct download: 32_PrefabNZ_with_CEO_Pamela_Bell.mp3
Category:Building -- posted at: 10:26pm NZDT

How do you build a code 4 house for the price of code 3? And how do you get industry to solve the problem themselves?

Richard Buchanan is an Associate Director at BRE and Founder of Green Building Consultancy Ltd. I met Richard recently inside a LinkedIn group during a discussion about housing affordability. 

It turns out that while we're all looking around for policy solutions and government intervention here in New Zealand, the UK building industry has already figured out how to build better homes, for less. And they did it by collaborating together. 

Richard explains what a Code 3 and a Code 4 home is and describes the aimc4.com project that successfully helped the industry produce more efficient and healthier homes, without any additional upfront cost.

Some links that Richard mentions in this episode include:

Direct download: 18_How_to_Build_to_Code_4_for_the_Price_of_Code_3.mp3
Category:Building -- posted at: 10:06pm NZDT

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