The Pretty Good House

A Pretty Good House should:

  • Support the local economy. That means building with local labor, with locally available and/or produced materials, as much as possible.
  • Be commissioned following construction, and be monitored on an ongoing basis. If you don’t know, and to me it’s a strange use of the word, commissioning means testing how the house performs after it’s built.
  • Have operating costs that are minimal or reasonable.
  • Have R1.8-R3.6-R6-R10 insulation. Hopefully these numbers are obvious: they represent a “pretty good” level of insulation in a cold climate for sub-slab, foundation walls, framed walls, and roof or ceiling, respectively.
  • Measure 90-140-160-180 m2. These number are probably not as obvious; they represent an allotment of square feet of living space for 1, 2, 3, and 4+ inhabitants, respectively. It could be less — the national average is much more — but as a group we thought this was… pretty good.

What’s in and what’s out?

We came up with a list of what is in versus what is out of a pretty good house. What’s in:

  • Superinsulation.
  • 4 inches of rigid foam under the basement slab.
  • A service core for plumbing and wiring (à la Tedd Benson’s Bensonwood concept, also a feature of A Pattern Language (Alexandar, et. al.): keep services out of exterior walls, grouped for easy upgrades in the future.
  • Energy modeling (performed during the design process).
  • Adaptability/durability/recyclability. For more on this topic, see Alex Wilson’s blog, “Ensure Durability and Reuse Existing Buildings.”
  • An air leakage rate of no more than 2 ACH50. Not exactly Passivhaus, but… pretty good.
  • Good design. I was surprised it took so long for someone to mention this. A good house has to look good and feel good, not just function well.
  • An owners’ manual. I know that Michael Chandler has written about this. You get an owners’ manual with your car, DVD player, and electric toothbrush. Shouldn’t the biggest, most expensive, most complicated thing you own have an owners’ manual too?
  • Universal Design. Our population is getting older, and people are realizing that having a disability does not mean one’s lifestyle needs to be limited. For the most part, Universal Design is smart design.
  • Comfort. Recently I was at Chris Corson’s Passivhaus project on a cold day. There were no drafts, no cold spots in front of windows, and only a single Mr. Slim heat pump for the whole house. It was comfortable. I’ve been in $20 million dollar houses that were not comfortable (and probably insulated with fiberglass batts).

Keep it simple

What’s out:

  • Passivhaus under-slab insulation. 10 to 14 inches of foam? As great as many of us think the Passivhaus standard is, it’s still hard to imagine using that much foam under the slab.
  • Toxic/unhealthy materials. Duh.
  • Too much embodied energy. Spray foam is a great insulator, but it comes at a cost. Vinyl siding is cheap and (somewhat) effective, but it comes at a cost. Bamboo flooring comes at a (transportation) cost, and having installed quite a bit of it, I don’t think it’s all that great….
  • Diminished returns. The idea of the Pretty Good House is to find the sweet spot between expenditures and gains. When is enough insulation enough?
  • Complexity of structure. With modern living space “needs” and small lots come oversize houses. One way to reduce the apparent scale of the house is to chop up the roof with dormers, pepper the walls with bumpouts, and otherwise create places for ice dams, air leaks and extra construction labor and materials (see Martin’s blog,“Martin’s Ten Rules of Roof Design”). I’m guilty of frequently designing in dormers to the renovations and additions I work on, as a way to buy extra space while respecting the original architecture…but at least I’m aware that it’s a problem.

Source: The Pretty Good House

Featured MicroArchitecture R&D

Energy and the Sustainable House

We think the point of sustainable housing is to support living without being locked in to a high rate of consumption of resources.  For example, energy is a big concern.  The chart below shows the average energy use of a New Zealander, per person, per day, in kWh. For conversion, 1 kWh of electricity is about $0.25, and there is 10kWh of heat energy in 1 L of petrol.
This chart shows that for the average person, more energy goes into producing our food than in heating our houses. And consumption of goods (stuff), is the largest energy use.  On average, we each use 3.1 L of petrol per day in our car.  For a sustainable house, we must make reductions in each of these categories.  In the category, Home Energy: we could make the heating efficient with heat pumps, and make energy use low or positive with photovoltaics.  For car travel, pick a site that is bikeable, and make facilities for bicycles in the house. For stuff, pick a decorating style that does not require frequent refreshes. Make the house design flexible so it is not demolished and has a long life.  For food, design for a garden.  For plane travel, pick a frequent holiday destination that is within your country.
Featured MicroArchitecture R&D

Wetting and Drying of Timber Framed Walls

[Excerpted from Finch and Straube, 2007]
“It is well accepted that moisture is one of the primary
causes of premature building enclosure deterioration. Excess
moisture content combined with above-freezing temperatures
for long enough will cause rot, mold growth, corrosion, and
discoloration of many building materials. The four major
moisture sources and transport mechanisms that can damage
a building enclosure are (Figure 1, left side):

  1. Precipitation, largely driving rain or splash-back at grade
  2. Water vapor in the air transported by diffusion and/or air
    movement through the wall (both to interior and exterior)
  3. Built-in and stored moisture, particularly for concrete or
    wood products
  4. Liquid and bound ground water, driven by capillarity and

At some time during the life of a building, wetting should
be expected at least in some locations. In the case of a bulk
water leak, drainage, if provided, will remove the majority of
the moisture from the wall cavity. However, a significant
amount of water will remain absorbed by materials and
adhered to surfaces. This remaining moisture can be removed
(dried) from the wall by the following mechanism (Figure 1,
right side):

  1. Evaporation (liquid water transported by capillarity to the
    inside or outside surfaces)
  2. Evaporation and vapor transport by diffusion, air leakage,
    or both either outward or inward
  3. Drainage of unabsorbed liquid water, driven by gravity
  4. Ventilation by convection through intentional (or unintentional) vented air cavities behind the cladding

A balance between wetting, drying, and storage is
required to ensure the long-term durability of the building

Featured MainMenu

2014 Challenge Winners

SHAC Popup Challenge 2014
2014 SHAC Popup Challenge winners have been announced!
The winners Mizu Tea House pops-up in busy, downtown Auckland to provide an escape from demanding daily life, and Studio56 is a Dunedin break-out space that provides a unique learning and collaboration environment.
Highly commended, Flowing Tyres is an urban garden like pavilion.
The teams are now working to build their projects. Which team will finish first?
Over 50 submissions were received from all over New Zealand. Teams worked to design a playful pop up structure to help designers, builders and the public better understand the art and science of sustainable building. Teams responded to the challenge to show how we all can live well with less need for resources. SHAC promotes design as a collaborative, playful process that generates and evolves good ideas. Winners receive a SHAC trophy, a mark of industry accolades.
About SHAC
[SHAC] is a network of designers, builders, engineers, and architects who want to build a better way. SHAC is addressing the need for a more sustainable built environment. We host competitions and workshops to find good ideas and connect people. We work on innovative small-scale building projects for clients and their community.
Tim Bishop, Coordinator, SHAC | 021 705 346
Laura May, Team Coordinator, Mizu Tea House | 021 118 6039
Alice Perry, Team Coordinator, Studio56 | 027 335 1654 –> Press Release
Naomi Thompson, Team Coordinator, Flowing Tyres | 022 646 2818

challenge Featured MicroArchitecture

PopUp! – Sustainable Habitat Challenge 2014 Call for Entries

Photos and/or drawings of your pop-up structure due 20 August 2014 12:00 noon.  On two or more A3 sheets.  Please email your submission to
What Pop-Up structure will you create?  A sculpture, a shop, an office, a venue, a place to play?

Competition Objectives
* Provide a playful competition to help designers, builders and the public better understand the art and science of building.
* Promote design and build as a collaborative, evolutionary process
* Promote the re-use of materials
* Promote living well, with purpose, and with less reliance on money and resources
* Promote creative responses that do not require a large budget

Entry Requirements and Checklist
* Register for your number here
* Please email your submission to
* Due Date – 21 Aug 2014 12:00 noon [NZ time] * 150 word description of the project in the body of the email [same as described below] * ProjectName-SubmissionNumber-A3.pdf
* ProjectName-SubmissionNumber-image.png   [or .jpg or .gif] * ProjectName-SubmissionNumber-any other file   [could be sketchup, pdf of photos, etc] * The PDF A3 presentation sheets are what explain the project. This may include sketches, plans, elevations, sections, and/or photos of the materials or techniques to be used.
* Entries not to include your names or logos, only your assigned submission number.
* In 150 words or less explain the following:
a) The project and its purpose, it’s present and potential future uses.
b) Possible methods of construction
* Submitted designs should be copyrighted by the author(s) under a Creative Commonslicense of your choice, suggested: “CC-Attribution” or “CC-Attribution-NonCommercial
* SHAC reserves the right to not accept any entries.
* Best entries will be honoured with awards and prizes.
* All entries may be published by SHAC on our web site or other medium.
* Thank you for your submission!

Featured Projects R&D

SHAC Green Roof Technology Demonstration

SHAC Green Roof Technology Demonstration, Christchurch, New Zealand

Open Source: Specifications [coming soon!]


10m2 Featured

Earth Systems

Japan is fascinating. The Japanese are so respectful of everything -work, other people, the natural world. And they have so many rituals – for me it seems to be a way to relax. Together it makes for a human society that is synchronized with the natural environment. Their technology is very efficient and they husband their natural environment so as it produces so many useful things from urban land, rural land, and even the forests. Japan is about 130% the size of New Zealand. And they are worried that they only produce food for about 40% of their population. That is 48 million people!
In early February I visited Tokyo and Kyoto. Tokyo is the megalopolis – it has huge apartment buildings that extend as far as I could see from the 18th floor of my hostel. Kyoto on the other hand is largely 2 and 3 story buildings interspersed with many decorative gardens, temples, and productive fields.
I presented at the “Earth Systems Governance Conference Tokyo 2013” at the United Nations University. Yes I fell off my chair when I was accepted to speak at this conference!!
The conference is trying to raise the point that all of humanity is a system “governed” by written and unwritten, or formal and informal, rules and norms.
The conference did attract many presenters on top-down international relations and nuclear energy policy, however the project is also about “bottom up”, grassroots changes in our human-made earth system.
It was a fascinating conference – I was astonished that the people that consider big global issues find what we are doing in Christchurch interesting.
Presently, in New Zealand, the current set of unwritten rules and norms say: “houses are very expensive; spending 5 times your annual income on your house is the best way to save for the future; building a house is best left to the experts; group action is ineffective; excellence and high performance is the sole realm of the highly trained professional; making positive change in your life is profoundly difficult and best left to the experts.”
I presented on the emerging network of groups in Christchurch that are showing other possibilities and suggesting new norms.  These groups are creating new possibilities and presenting new ideas that will likely lead to a more sustainable built environment.
One key idea is that we use volunteers and skilled people collaborating together. Another is that you don’t need to be a highly trained person to start something.
There is an informal network of groups in Christchurch that have responded to the earthquake are rewriting the informal rules, and creating new norms. These groups include Greening the Rubble – [gardens can be anywhere!], Gapfiller – [life is a stage!], CPIT – [we are learning by doing!], Live in Vacant Spaces [there are other ways to access land!], The Concert [volunteers are effective, and it is very fun!], Rekindle [we don’t have to throw those building materials away!], White Elephant [young people create and do!], Renew Brighton [a community can remake itself] Maybe one day the formal rules could change, in response.
Written rules also have an impact that was recently documented by Stu Donovan on

The primary impact of local government regulations is not through the constraints they place on land supply (i.e. urban containment), but actually through the barriers they create to the development of more compact and affordable housing. Here’s some examples of regulations pursued by local governments in New Zealand that seem likely to restrict the supply of affordable housing:

  1. Minimum lot sizes – i.e. “all ye who have less money shall be forced to purchase land you don’t want.
  2. Minimum apartment sizes – i.e. “all ye who have less money shall be forced to purchase living space you don’t want.
  3. Minimum parking requirements – i.e. “all ye who have less money shall be forced to pay for vehicles you don’t own”.
  4. Maximum height limits – i.e. “all ye who chose to live like rats are consigned to perish like rats – on the street.
  5. Heritage protections – i.e. “all ye who don’t have the money to renovate a villa shall live elsewhere.

The Earth Systems Science Plan defines the five analytical problems of governance. The five A’s, for short: Agency – to what degree groups and individuals feel like they can act to create positive change. Allocation and Access – how individuals and groups are allocated or access needed resources like land, housing, food. Accountability – projects are legitimated – how do we know about, participate in the decision making around projects that affect or interest us? Adaptiveness – how do we change or reorganize in response to needs? And finally, Architecture – what structure of organization allows for good outcomes in the other areas? For example, what type of command and control, what processes or procedures, or what norms?
In Christchurch we have a loose network of groups that come together for various projects as suits each group. Each group thus retains its own agency – the ability to act. There are no formal contracts between groups that restrict or prohibit action.  Each group has a few energetic coordinators who harness the capacity of skilled professionals and keen volunteers/apprentices. No explicit coordination between groups is needed. Each group’s actions are coordinated by skilled and resourceful coordinators who keep the momentum going.
Projects are “legitimated” when people volunteer to do them. Good projects are supported by volunteers. Employees do what their bosses say, but volunteers only work on things they believe in.  More volunteers equals more legitimacy equals more impact. It is unlikely that an unpopular project will have a big impact, while popular projects will grow and grow.
And It seems that from this architecture of a loose affiliation of interacting groups, supported by a mix of volunteers and professionals, emerges a system that can support a more sustainable built environment.  In other words it supports supports multiple groups to have agency, to have legitimacy, and to demonstrate other ways of allocation and access to resources.
Will this hodge-podge of groups lead to a more sustainable built environment? This is still to be discovered. I had an intuition that this was the case, and the conference introduced me to the academic literature further supports this case:  That small, self-governing systems of local groups do effectively and fairly allocate limited resources. See, for example, the work of natural resource economist Elinor Ostrom.
We are prototyping possibilities for the future today!

10m2 10m2 Challenge Entry Featured MicroArchitecture

2012 Sustainable Habitat Challenge Entrants

Central North Island Featured New Zealand

Clean Energy Centre explores possibility of off-grid housing community


Taupo could be in for a new eco-sustainable housing community, reshaping the way houses receive heat, electricity, water, and use wastewater.

The New Zealand Clean Energy Centre (NZCEC) is currently investigating whether or not this would be feasible.

The community would use geothermal or biomass heat to heat homes; generate electricity from solar and wind sources; and reuse wastewater by drip-irrigating it to energy crops to provide future fuel for the community.

NZCEC said out of 75 people surveyed over the last two days, 33 had been in favour of the idea.

“The New Zealand public has demonstrated a keen interest in adapting their lifestyles to live in ways that are friendlier to the environment. They want to do their part to help maintain NZ’s 100% Pure, clean green image, they want to find ways of reducing their energy bills, and they want to increase their control over energy supply security,” says chief executive Rob McEwen.

He says the project would benefit  Taupo’s economy, enticing domestic and international migrants, especially Silicon Valley entrepreneurs looking to make New Zealand their home.

McEwen believes the pitch to these potential residents would go something like this:

“Taupo generates 75 times more clean energy than we consume (and thanks to geothermal, that ratio is growing). We have magnificent natural beauty (think of Taupo as the Tahoe of NZ), we have world class fibre optic internet, we have ample water, we are central to 75 percent of NZ’s population, we are home to the NZ Clean Energy Centre and oh, by the way … Taupo is developing a comprehensive off grid sustainable lifestyle community.”

 He says the next steps are to further quantify interest, then develop the concept to include drawings of the proposed community, a 3D animated walkthrough, and costings.

One way to make it feasible would be to use  semi-rural land on the outskirts of town so that homeowners’ investment in the land would be lower.

“Another way is to negotiate reduced development contributions with council. Unlike a typical subdivision where council needs to put in a lot of infrastructure such as water, waste water, power reticulation and phone connections, none of those services would be required in an off-grid community,” says McEwen.

>>> Clean Energy Centre explores possibility of off-grid housing community :: Idealog 

10m2 Canterbury Featured MicroArchitecture

Office to rise from the rubble

One person’s rubble might be potential material for Gap Filler’s new office.

Sustainable Habitat Challenge (SHAC) and ReGeneration Trust New Zealand are collaborating to build an office for Gap Filler in Colombo St, Sydenham, with the help of volunteers and as many recycled or sustainable materials as possible.

Gap Filler project co-ordinator Coralie Winn said she was humbled by the plan.

“It’s a very generous gesture that they are doing this for us and also teaching young people building and design skills,” she said.

Gap Filler, which emerged after the September 2010 earthquake, has overseen several urban regeneration projects, such as the Lyttelton Petanque Club, the “book fridge” and the painted-piano project.

It has been based in Winn’s front room.

“Since November, we’ve hired a part-time helper, and people have been coming and going,” she said.

“It will be great to have an office that’s not at home. It would be quite nice to fill a gap with our own office.”

SHAC’s Tim Bishop said the frame of the 10-square-metre office would be built from recycled timber from demolished buildings, and the windows would also be recycled.

Waste polystyrene would be used for insulation, while the external walls would be constructed from wooden pallets usually used for transporting heavy goods.

“We want to show how to creatively reuse material left over from the earthquake. It’s a bit of a test. A few things are going to be new, like nails and building paper,” he said.

The project also aims to show young people that it can be easy and fun to build small buildings with sustainable materials.

Demolition and salvage yards, including Southern Demolition & Salvage, Musgroves and the Window Market Place, are also involved in the project.

The Christchurch Polytechnic Institute of Technology is contributing equipment and helping to find a licensed builder.

The build will take a week, from January 23 to January 28.

Volunteers can sign up here.


via Office to rise from the rubble – the-press |