Author Archives: timb

Household Moisture – Its in the Furnishings and Materials

Household moisture primarily resides in the building materials and furnishings in a house.  Think your big, damp mattress, for instance.

Damp materials in your house keep your relative humidity high.  And releasing humidity into the air means that moisture will eventually find its way inside your couch, or in other furnishings or building materials.

Here is a simple chart of the equilibrium relationship between moisture in the air (RH), and moisture in materials (MC), expressed as a percentage of the mass of the material.

This chart can be read as follows:  If you house averages 70% humidity, you can follow the 70% RH line and see that spruce wood (similar to pine), will have about 13% moisture content.  Given that your house will have thousands of kg of pine in it, this chart means there will be hundreds of kg of water in that material.  And the same with wallboard, insulation, soft furnishings, and your carpet.

For experimental purposes, or for learning with school kids, a simple hygrothermal (heat and moisture) model of a house can be built as so:

Read about our recent research with the Valley Community Workspace community group: (PDF)

Also see “The Wetting and Drying of Timber Framed Walls

Damp Homes

Imagine, if you take a cold and damp house, and then wrap it in extra insulation and draughtproofing.  What do you get? A warm and damp house.  The extra insulation and draughtproofing reduce the air circulating in a house, which is a reduction of the ability for a house to dry itself.

How do we get a warm and dry house?  Capture the sun, add heating to the house, and add ventilation. This can be as simple as ensuring the windows of a house are open during the day, especially when it is sunny out.  Or you can add some sort of ventilation system that takes in outside air into the house.  Your heat pump does not do this – all a heat pump does is recirculate the damp air that is already inside your house.

On the whole, outside air is dryer than inside air, especially once it is heated to inside temperatures. This is why bringing outside air into the house helps to dry the house. There is some cost to heating outside air, but the benefit is a dryer, healthier house.  Also, if a ventilation system is used, this cost can be reduced if a heat recovery ventilation system is used. Of course using windows for ventilation is the cheapest option of all!

Psychrometric chart showing WHO recommended temperature and humidity (green+blue region), and room measurements for one week. Each point is average temperature and humidity for one hour. Different times of day are coloured differently.

Most of the moisture (>85%) in a house is in the furnishings and building materials in the house. Simply removing moist air once will not dry a house, as dampness will just evaporate from furnishings and building materials, and the air will quickly become damp again, within minutes. A damp house needs repeated flushing of the air within the house so that the furnishings and building materials within the house slowly begin to dry.

Read about our recent research with the Valley Community Workspace community group: (PDF)

Also see “The Wetting and Drying of Timber Framed Walls

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

Addressing the challenge of climate change together, activists and designers

… Climate activism has primarily manifested as “Blockadia.”  Why? Blocking and shutting down bad projects is easier to organize around than efficiency or carbon pricing. And maybe that’s fine. Maybe it isn’t the role of activists to imagine and bring about a new world. Maybe that’s for policymakers, designers, engineers, artists, and entrepreneurs.

Source: Architecture and Climate – what critics misunderstand about climate activism

Hutt Shelter [2015-80]

The starting point for this design references the traditional timber framed barns once common in Canterbury. Occasionally you come across a barn nearing the end of its life, with bleached and weathered timbers. The roof framing is letting go, and a graceful curve develops in the ridge line as the building becomes more beautifully integrated into the landscape.
This building will be an ambassador for natural building. For many it will be their first encounter with these technologies. As such it should be relatable, distinctive, dignifying; a building that people can identify with. At the same time expressive of the materials used.
In this design the main materials are sourced from the nearby landscape. Wheat straw from the surrounding farmland; lime from Amuri for plaster; macrocarpa from farm shelterbelts for frame and cladding; bricks for the floor salvaged from the Canterbury earthquakes; and river stones for the sheltering wall along the south.

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Shingle Point [2015-77]

Shingle Point
Inspired by the jagged peaks of the Southern Alps and the timber boardwalks on our national walking trails. Shingle point looks to a regenerative future and harks back to simple timber settlers cottages. With native timber flooring, framing, sarking and cladding the intended structure would be formed from our natural resources. Reclaimed Totara heartwood is proposed for its inherent durability. This timber was highly prized by both the Maoris and the early European settlers. It needs no chemical treatment and can be oiled to retain colour or left to silver naturally. A faceted Greywacke stone plinth is also proposed to anchor the structure, form the seating and elevate the timber from ground moisture. These materials and the form are intended to blend into Methven’s built alpine vernacular and relate to the areas dramatic natural landscape.

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Snöhuttë [2015-69]

Snöhuttë is a bus shelter located on the out skirt of Methven, 47 Racecourse road, besides Ski Time resort. Its primary function is to serve as a shelter for tourist and locals waiting to head out to the local mountains for winter activities via bus transport. The shelter comfortably accommodates 20 travellers and their gear, whilst keeping them warm courtesy of the fire place within the feature wall that also doubles as a chimney. The shelter can also function between winter seasons as a communal space by transforming the entrance wall to create an additional covered outdoor area. Materials used to create the shelter are natural stone for the base and feature wall, rammed earth southern wall, and pine timber to create the inhabitable spaces with north facing glass windows. The sloped roof prevents snow from collecting on the roof, the covered entrance way provides an intermediate transition that combats the strong north westerly winds, and rest of the shelter is completely sealed to combat wild weather conditions of Methven.

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Cafouillis Shelter [2015-68]

Hey! so our design is made out of steel beams for the structure and correlated iron for the back cladding, the interior is lined with untreated timber, the interior bracing elements are also timber and are held together by stainless bracing (pictured in poster). Our design was inspired by the norwest arch, geodesic domes and also the dna helix.

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ONTRACK [2015-67]

ONTRACK is about bringing back Methven’s heritage. We will revive the railway by creating a shelter out of rail tracks.
The rails will form the structural frame of the shelter, and recycle materials from Christchurch such as: stone, timber and iron roofing will be used to create the walls, floor and the cladding.
The bus shelter is about 30m2, with 2 entries (one from resort, other one from the road), ski storage, covered seated areas and have great visibility on the road.
It is protected by timber panels that are hooked onto the structure and the shelter is positioned to receive the most sun in the morning but also to protect from the south and western winds.

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Tyre Garden [2015-63]

The Tyre Garden on Racecourse Avenue is a multipurpose shelter for passengers and guests of the resort anytime of the year, as well as reflecting the farming culture found in Methven through the reuse of farming materials in the surrounding garden.

The structure of the shelter is constructed from recycled materials, the walls made of used tyres rammed with earth to help minimise the effect of seismic action commonly encountered within the Canterbury region. Wooden pallets form the structure of the roof and is thatched with bales of straw. Angled walls provide views to Mount Hutt and offer protection to passengers from the prevailing winds (as well as providing a view of the incoming bus), but open to allow for vegetation blossom through the exposed tyres.

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Whare Whenua [2015-59]

This is our Entry – Whare Whenua

Whare Whenua is bus shelter created from natural materials. Rammed earth walls shelter the users from oncoming words and help support the angled steel roof that is inspired from the southern alps seen fro the site at 47 Racecourse Avenue. Untreated Timber louvres, which are used as an architectural element also helps with shelter from the winds and while showcasing the idea of a rising mountain. During winter seasons skiers and snowboarders can hang the gar on the wall and during the non winter periods the bus shelter can also be used an area to come and hang for the community.

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Curv [2015-55]

Curv ski-bus shelter is designed for the people and community of Methven. The shelter is designed from locally sourced materials. Curved walls made from adobe bricks, an elegant roof constructed from timber and recycled tires. The chosen materials are all natural and recycled other than that used for structural purposes, these materials also relate to the climate. Adobe bricks offer great thermal properties, the recycled tires are weatherproof also concrete, timber and steel reinforcing is used to keep its structure intact. Construction is fairly easy and best of all these materials are cost efficient. Curv is designed to bring in the sunlight and works against prevailing chilly winds of Methven and in the case of the rare storm winds the shelter provides seating on the south side of the dwelling and an amphitheatre-like seating inside for the tourist crowds in winter season, the space also serves a dual purpose for gatherings and performances for the community when its off season.

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Seven Summits [2015-50]

Seven Summits arises through the grounds of Methven to replicate the beautiful aesthetic of the mountain summits in the horizon. Not only a bus shelter, but Seven Summits provides a space for communities to gather with one another through an engaging environment. A community garden brings together people of multiples ages and interests, thus bonding the small town of Methven and creating a future of innovation and entrepreneurship. The main goal of Seven Summits was to create a space that would be able to interact with environment and also to link that connection with the people of Methven. Each peak tells a different story, therefore the heights were altered so that this could be signified. The stone walls represents structure and safety, helping block the cold winds of the south and furthermore the strong gusts of the north.

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47 Peeks [2015-48]

Bring the mountain tops into Methven. Located at 47 Racecourse Avenue, the sculptural bus shelter allows mountain goers to peek at spectacular views of the Southern Alps while protected from chilly Methven winters. Usable public space close to town center will create a land mark attracting tourism year round. Revitalised steel beams and roofing from Christchurch’s earthquake damaged buildings, requires little processing and transport, so will be cheap and easily to replace if damaged, as materials can be repurposed or recycled with no waste into landfills. The easy to maintain structure will be lifted off the ground to allow for air circulation to keep shelter clean and reduce the wind tunnel effect. 47Peeks is the ultimate recycled material bus shelter that will breathe new life into Methven.

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1976 [2015-45]

On track to greener materials

A prominent railway history establishing in 1880 and spanning to 1976. With only four years short of a centaury of operation, the railway is an iconic part of Methven’s history. A cornerstone in building the town and a part of its heritage that’s not easy forgotten
Situated on the Canterbury plains at the base of the Southern Alps, Methven has a remarkable landscape. Luscious green fields surround the township with the snowy mountain range establishing their presence to the west. A fantastic example of rural New Zealand, showing off gorgeous scenery that our country has become celebrated for.
A green, sustainable transportation hub for the town of Methven. Mimicking the habitat, 1976 does justice to the landscape by blending into the surrounding context. Acknowledging the townships vibrant locomotive history and utilising recycled materials creating a nostalgic emotional connection to the yesteryear of Methven. Recycled railway sleepers, and tracks, untreated Douglas Fir logs, and Locally quarried stone make up the construction materials for the scheme. All materials are sourced locally with minimal embedded energy.

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Lashed Earth [2015-40]

Lashed Earth is a shelter designed using natural and recycled materials from around the local region. Its purpose being able to shelter tourists or members of the community waiting for the bus not only during the winter from the cold whether like the rain, snow or the strong winds and also act as a shelter during the summer from the heat, the sun as it has functions in the design that can act as shelter. Its been designed to be strong enough to hold up during natural events such as earth quakes with its support structure inside which acts as a secondary support for the shelter but also something that is quite unique and quite monumental for tourists / visitors to look at with its unique way of holding it up with traditional lashing methods that in some peoples eyes act as a type of art work in a way. The name of the shelter comes from the way the shelter is constructed. Lashed Earth is a simple designed shelter with multiple purposes but the main one being able to shelter people from the cold weather or the hot weather.

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Euclidean [2015-38]

We chose the name Euclidean as it defines the general feeling that the concept of space is ultimately a mathematical one. The Euclidean has been designed to create a space habitable for all demographics and their needs as well as promoting a social environment with the interior curves to create comfort while waiting for the bus. These curves purposefully juxtapose the perpendicular exterior structure to create a new ambiance as you enter the shelter. We create elements which do not look foreign to the space; All seating areas are built into the walls. Columns are used to create a threshold are exposed beams allowing the patrons to view their ski gear from the seating area. In summer, the space is owned up by the large window on the roadside. The seating along the window also acts as an exterior bench, allowing you to view the grand surrounds of Methven.

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Ground Up [2015-36]

This Shelter is designed with simplicity and function in mind with a minimal material palate of rammed earth and reclaimed timber the embodied energy is kept to a minimum. The delicate roof was designed to float in between the vertical monolithic walls, this allows for radiant heating. A small separation from the horizontal bench mass and the vertical walls creates a dynamic space connecting the two seating areas with light and sound. Dubbed “ground Up” due to the process of using the earth below to create a structure.

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Sunset Stripes [2015-30]

Our project consists of rammed earth walls, Douglas fir panelling and seating, a concrete floor, and steel roofing. There are two entrances, the main one opening onto the road, and a smaller secondary entrance at the rear of the shelter allowing access from the resort. The walls at the back overlap at the entrance to stop the cold southerly winds entering the shelter. There is vertical panelling on part of the front entrance to deflect the chilly North Westerly winds while allowing in the morning sun from the East. The main opening faces North allowing sun to stream in all day and views of Mt Hutt. The rammed earth walls combined with timber panels and seating give the shelter a warm and cosy feel. The roof drains to a single point at the rear, then trickles down a chain drain into a small wishing well. It seats approximately 16 people.

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Host Ship [2015-24]

Host Ship is situated in front of the Methven Resort and across the road from Mount Hutt College. Three structures are arranged along the site. The shelters are made of locally-sourced materials: cob, corrugated iron roofing, straw, recycled steel and timber. A wall made of earth and straw is used to support the angular roofs which connect to a down pipe. Snowsport gear can be placed into a timber frame that is attached to one of the structures. The most northern shelter is to be built by the high school students at Mt. Hutt College. This will allow students to make their own space where they can organise events or just hang out after school. During the quiet times of the year, the space could be used as meeting point for tourism or a performance space, thus making this a flexible space for the local community.

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Methven Mountain Shelter [2015-23]

Methven Mountain Shelter is a unique semi-enclosed bus shelter that caters to travelers and to the community all year round. It acts as a shelter during the winter, a communal gathering point during summer and a historical information centre throughout the year.

The main aspect of its design is to reflect the environment surrounding the site. Consequently altering the buildings shape best suited for view of Mt Hutt, Vision for approaching buses and the weathering. The design is to be rustic, using mixture of recycled and sustainable materials. Its façade shape is to reflect the mountain ranges and Mt Hutt.

Materials included are weather boards from the Christchurch earthquake in original context as the facade to enforce historical importance of the Canterbury region. The remaining structure is made from straw bale (Non-load bearing) and timber from Douglas-fir (Load bearing) to support the recycled roofing.

This design is copyrighted by the authors under the CC-Attribution License

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Rerehi Whakarutu [2015-21]

Rerehi Whakarutu

For our Shac bus shelter proposal we explored the concept and ideas behind curves that could be achieved using straight lines and arranging them using horizontal and vertical axis. We used this to replicate the rigorous mountain sides and combining this idea into our proposal. We wanted to achieve a shape that not only looked interesting but contrasted from the landscape that it was surrounded in. We included this idea in the roof construction of the project. The materials were sourced locally and provided a low and effective solution and helped reduce the overall carbon footprint of the bus shelter. With a combination of wooden shingles and a timber frame construction the bus shelter was primarily focused on natural materials and its conventions. We wanted to move away form the traditional bus stop design of a roof and walls to something that was unique in its own way.

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Earth Circle [2015-19]

Earth Circle

Earth Circle is situated in front of Methven Resort and across the road from Mount Hutt College. Three structures are arranged in a circle, forming an open space in the centre.
The structures are made of locally-sourced materials: rocks, earth, straw, recycled timber and recycled polycarbonate sheet. Gabion blocks (wire mesh filled with rocks) form double-levelled bench seating. A cob wall (made of earth and straw) behind the benches is framed by two recycled timber posts, which support a light roof of polycarbonate and timber. Skiis and snowboards can be slotted into a timber frame that is attached to one of the structures.
The structures are simple and easy to build. This allows for the Methven community’s involvement in the construction and maintenance of the structures, making the project more broadly sustainable (not just in terms of its materiality).
The open, communal space is suitable for use throughout the year, while it is not occupied by seasonal visitors, as a market or performance space.

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Sticks & Stones [2015-18]

This unique and dynamic bus shelter crafted using carefully selected hearty South Island materials creates a safe haven from the Methven environment throughout the seasons. The positioning of the Shelter allows for easy circulation between the resort car park and the footpath. “Sticks & Stones” originates from the shelters solid stone central wall with protruding wooden logs which offer a number of waiting areas and gear storage benches. “Sticks & Stones” is an ideal Bus stop in winter and a playful and calming picnic and family area outside the resort in summer.

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Off the Rails [2015-17]

“Off the Rails” relates to the historical context of Methven. Tapping into the lines of Methven being the terminus of a historical railway system of the late 1800’s. The frame is comprised of a skeleton of recycled railway sleepers supplied locally in the Canterbury region. The walls are made up of local, recycled pallets in filled with a layer of cob, for strength and shelter. by up-cycling these materials we are transforming what was previously the end of a journey into what now facilitates the beginning of one. These materials also provide an earth and farmyard aesthetic that ties into the Methven experience. Located on Racecourse Avenue near the Ski Time Methven hotel. The shelter caters comfortably for 20 people all year round and provides a suitable shelter for all weather conditions. With its move-able barn doors and variety of seating arrangements our bus shelter will make a trip to the local mountains a social and enjoyable experience for all.

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PDF (7.6MB)

MTSCAPE [2015-14]

This is a bus shelter made from natural and recycled materials designed for skiers and snow boarders in Methven, travelling to Mt. Hutt. For this reason the design is inspired by the mountain range of Mt. Hutt. The bus shelter is made from a combination of rammed earth pillars, straw bale walls and recycled corrugated iron roofing. The design is located on the site next to Methven Skitime on Racecourse Avenue.

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Mountain View [2015-13]

Inspired by the beautiful mountain view of Mt. Hutt from the site, the Mountain View bus shelter allows people to enjoy the spectacular mountain scenery while waiting for the bus to arrive. The bus shelter also incorporates natural materials such as straw bale, local wood (Douglas fir), and green roofing to provide a sustainable and aesthetically pleasing shelter for both the tourists, and the local community of Methven.

Materials used are the following:
Strawbale plastered with lime for the south part of the bus shelter that functions as a load bearing wall, which withstands southwesterly prevailing winds.
Also a great natural and sustainable material that provide insulation
Untreated local (Douglas fir) wood used for the overall framing of the shelter.
Recycled glass are used for the visibility of the mountains, which also functions as a wind blocker for the North West cold wind.
Extensive green roofing for the flat roof of the shelter, which uses local small plants that could survive strong winds.

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Silhouette [2015-11]

Silhouette provides a joyful social space for people to socialize. Creating sun shadows from recycled pallets.

Recycled pallet is not only used for walls and roof, but also been used as frames for construction which is resourceful, inexpensive.

Foundation is made with river stones collected from Rakaia River.

Ski gear can be stored in the gaps between pallets elegantly.

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Thermal Performance of Curtains, and other retrofit options

A couple common questions:

“What is thermal resistances of window film with an air gap, and curtains?”

  • Timber framed window, single glazed (baseline)
    • R0.2
  • Timber frame, single glazed, with drapes and pelmet
    • R0.3 $0-$150/m2
  • Timber frame, single glazed, with window film
    • R0.4 $5/m2
  • Alu frame, thermal break, double glazed, low-e
    • R0.4 $450/m2
  • (Higher R values mean less heat loss)

“What are good retrofit options for my home”?

Reducing heat loss is one important strategy.  (Another is maintaining ventilation)

Good strategies mean picking the most reduction in heat loss, for the least cost.  This chart can help.


Bishop, T. W. (2009). Heat Losses and Gains in Residential Housing in Southern New Zealand (Thesis, Master of Science). University of Otago. Retrieved from


Nine single person units built by young homeless people for themselves

“The project was for 9 single person homes on a small plot adjacent to a disused canal in Peckham – to be self built by local young people in housing need. The build was linked to a local training centre where the self builders were trained up to NVQ level 2 Carpentry and Joinery.

Consortium, a local umbrella group of housing charities, employed a worker to research the project and get it off the ground. This worker stayed on for the build process and acted as a support worker to the self builders. The site was managed by a full time site/project manager who had built on a previous self build scheme and who had youth work experience.

On completion of the scheme the builders became tenants of South London Family Housing Association, who had acted as development agents for the project

A very thorough and honest review report on the project is available from CSBA”

Source: Consortium

BSHF | Learning from informality

The cities of the future, which is what many urbanism conferences talk about, those cities that grow fastest, are not constructed out of glass and steel, but out of straw, recycled plastic, scrap wood, and bricks made of construction waste. Housing there isn’t built by the building companies, developers and policy makers who attend the conferences, but by people building for themselves.

Source: BSHF | Learning from informality

Solar Water Pumping Design

Wanaka Sustainable Barn

Off-grid barn with office, kitchen for agricultural prep, and solar water pumping


  • Off Grid
  • Office
  • 300 tree olive grove – needs 6 m3/day in summer • Kitchen for processing
  • Space heating required


  • Portal Frame barn – inexpensive, quick to erect
  • Insulated and heated with 8kw wood burner, 4kw wetback
  • PV system – 2.4 kWp, delivers 4 kWh/day in June, 16 kWh/day in January
  • Excess capacity in summer used to pump water, and heat potable water
  • House Electricity use – estimated 3 kWh/day in June, 2.5 kWh/day in January
  • Solar Water Pumping System – estimated 0.5 kWh/day in June, 4 kWh/day in January
  • PV and Pumping system very affordable
  • In depth simulations are in progress
  • House and solar system will be built in early 2013, and monitored and reported on


  • Commercial building design strategies like portal frames are cost competitive
  • Photovoltatic systems can be very cost effective when summertime energy can be used for a productive purpose. This system could pump up to 18 m3/day during the summer [from 80m bore]
  • No need to use solar thermal [solar hot water] systems that are likely to freeze

barn2 kwh L water SolarDiagram

Off grid two bedroom design

Dunedin 2-bedroom off-grid house.

Micro-hydro based renewable energy system with LiFePo battery backup.  Constant power from micro-hydro system means only a small battery is needed.

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Temporary projects leave long-lasting legacy

The temporary projects which popped up on newly vacant land around Christchurch after the earthquakes have a lot more value to a traumatised public than we may think.Dr Andreas Wesener, a lecturer in Urban Design at the School of Landscape Architecture has just published research on transitional community-initiated open spaces (CIOS) in Christchurch and says they have a range of benefits that might strengthen community resilience.His paper discusses benefits, possible long-term values and future challenges for community-initiated temporary urbanism in Christchurch.“Resilient people have been described as being able to find positive meaning and display positive emotions even in times of crisis, and introducing positive stimuli and engaging in positive activities have been considered vital in distressing post-disaster situations,” Dr Wesener says.There is evidence that people’s participation in temporary projects has encouraged positive emotions and creativity, strengthened social capital, such as community gardens, and fostered community empowerment within a challenging post-disaster situation, he says.“On an individual level, community members who lost jobs in the aftermath of the earthquakes reported that working on temporary projects had provided opportunities to cope with post-traumatic stress, remain active, learn new skills, establish new networks and in some cases job opportunities have been created.“Even passive passers-by without direct involvement in community-led activities may experience positive emotions solely by noticing that ordinary people are recreating and rebuilding structures within a destroyed urban landscape.”

Source: Temporary projects leave long-lasting legacy

SHAC Challenge 2015 – Call for Entries

Submit your design and be in to win prizes valued at nearly $1000 each!


Submit your design for a Methven, New Zealand, community bus shelter for approx 10-20 snow skiers and boarders waiting for the mountain pick up.  The best designs using natural materials will win free entry to the March 2016 International Straw Building Conference to be held 3-9 March 2016, in Methven, New Zealand. See for conference details.

Natural Building means using minimally processed and locally available materials for building, examples include, untreated timber, rammed earth, adobe, earthen plasters, straw, hempcrete, and others. Natural Building also means using solar energy efficiently and effectively.

Submissions due: 2 November 2015, 5pm NZT
On one or two A3 sheets.

Please email your submission in pdf format (max 15MB) to


  • Either Skitime, Methven –
  • Or, next to Methven Resort and the High School –
    This site may have some high schoolers using the bus stop during term time.  This site may need to incorporate the Methven Resort sign as part of the bus stop.

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 and the use of natural materials
  • Promote living well, with purpose, and with less reliance on money and resources
  • Promote creative responses that do not require a large budget

Judging Criteria

  • Use of natural materials
  • Innovation
  • Meeting competition objectives

Entry Requirements and Checklist

  • Register for your submission number here (
  • E-mail your submission to
  • Entries are individual or as a team of 2 people.
  • Due Date – 2 November 2015, 5pm NZT [NZ time]
  • Include a 150 word max description of the project in the body of the email
  • Name your submission ProjectName.pdf
  • 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.
  • Submitted designs should be copyrighted by the author(s) under a Creative Commons license 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.

Notes from Users of the Site – These requirements are advisory, not mandatory

  • Shelter from Southerly
  • Strong enough to withstand Nor Wester winds and the rain that follows.
  • Rack or similar for skis/snowboards
  • Blend in with existing buildings
  • Not to block views to the mountains.
  • Incorporate elements from their alpine and agricultural encounter.
  • A location for timetables and information to be displayed

Download Poster (2MB)

SHAC Natural Building Competition 2015

If Everyone Lived in an ‘Ecovillage’, the Earth Would Still Be in Trouble

We must swiftly transition to systems of renewable energy, recognising that the feasibility and affordability of this transition will demand that we consume significantly less energy than we have become accustomed to in the developed nations. Less energy means less producing and consuming.

An ecological footprint analysis was undertaken of this community. It was discovered that even the committed efforts of this ecovillage still left the Findhorn community consuming resources and emitting waste far in excess of what could be sustained if everyone lived in this way. (Part of the problem is that the community tends to fly as often as the ordinary Westerner, increasing their otherwise small footprint.)

Source: If Everyone Lived in an ‘Ecovillage’, the Earth Would Still Be in Trouble

Tiny home a true mansion

Her previous construction experience was a bookcase, but that has not stopped Lily Duval from building her own miniature house.

The 27-year-old is two months into the build, and is on track to have most of the construction finished in another couple of months. She is building her house directly on a trailer on communal land in central Christchurch. At 5.5 metres long, 2.5m wide and 4.2m high, Duval’s house fits under the New Zealand Transport Authority’s definition of a light simple trailer.

It requires no building consent.

Her house will cost $30,000 all up, which includes $8000 for the heavy-duty trailer.

via Tiny home a true mansion – news – the-press |

Interest growing for tiny homes

Christchurch man Bevan Thomas built his own “tiny house” from scratch last year and had seen “hundreds” through it over the past few months.

He believed the tiny house movement was becoming increasingly popular in New Zealand as people looked for ways to live with less impact on the planet, or to avoid being “tied to a half a million dollar mortgage”.

“There’s been phenomenal interest in it. It’s surprising actually how well the concept is taking off.”

Thomas built his moveable house after returning to Christchurch to look after family and finding himself at a loose end.

via Interest growing for tiny homes |

Tiny home at a tiny price |

Stefan Cook is revelling in the fact his new home cost $438,000 less than the average Christchurch house price.

Cook has now finished building his 3.4-tonne home, complete with a mezzanine bedroom, living area, kitchen and bathroom. The house measures 8 metres by 2.45m and is 4.1m high.

It was built on top of a custom-built trailer so it could be moved and did not require a building consent.

Cook did not have experience in building but it took him only 12 weeks to get it to a ”liveable” standard.

The building cost $22,000 – an amount he would save within two-and-a-half years by not having to pay rent – and most of the materials were salvaged from demolition sites, which helped keep costs down.

via Tiny home at a tiny price |

Student thinks small to beat rental trap

Christchurch student fed up with high rental costs is building his own “cottage on wheels”.

Stefan Cook is constructing the 2.5 metre by 8m transportable house in a bid to beat the rising cost of student housing and survive the Government’s withdrawal of student allowances for those undertaking post-graduate study.

The 34-year-old geology student at the University of Canterbury said he had been paying up to $160 for a room in a Christchurch flat during the first two years of his bachelor’s degree and expected his $15,000 project would pay for itself within two years.

via Student thinks small to beat rental trap |

Dunedin: Test drive a Tesla roadster electric car

Range and Power – Tesla convoy comes to Dunedin

Otago Polytechnic this Sunday 11th Jan at noon.  0-100km in 4 seconds.tesla

See for other locations around New Zealand.

A new kind of kiwi road trip is amp’ing up, as four kiwi blokes: Steve, Jay, Carl and Nick travel from Cape Reinga to the Bluff in a convoy of sustainable prowess.

The group #leadingthecharge are highlighting the practical and sustainable benefits of using electric cars. To drive home their message they’re cruising the length of the country in New Zealand’s first Tesla Model S car, and its only Telsa Roadster. Va va vroom!

According to the group New Zealand is ideally situated to benefit from the uptake of electric cars. “After the dairy industry, the next biggest source of emissions is our vehicle fleet, and since over 70 per cent of our electrical power is from renewable sources, there’re even bigger emissions savings with an electric fleet here than overseas.”

On their way South the foursome are stopping in to charge up at Otago Polytechnic’s workSpace. “We’re delighted to support the initiative and vision of these four kiwi men,” said workSpace spokesperson, Veronica Stevenson and “given our work in the sustainability and tech transformation space, workSpace is the ideal place for a meet, greet and test drive.”

The goals of #leadingthecharge are three fold

  • Charging – We aim to encourage private and public entities to roll out charging infrastructure all through New Zealand.
  • Driving – We want people to get into Electric Vehicles. Test-drives, car sharing, renting, owning. We don’t care how you do it; we just want people in these cars.
  • Teaching – There are so many untruths circulating about EV (electric vehicle) technology. We want to share true, well-researched and transparent messages about EV and all the benefits of EV ownership for individuals and New Zealand as a whole

All members of the public are warmly invited to attend this unprecedented event. Bring a friend, or the whole family – it isn’t often an event comes along that appeals to car enthusiasts and greenies alike.

WHERE: workSpace – A Block, Otago Polytechnic (across the road and up the grassy bank from the hockey turf on Harbor Tce)

WHEN: 1130am Sunday the 11th January


Veronica Stevenson: Story Strategist at workSpace, 027 4483036

Tim Bishop
SHAC | The Sustainable Habitat Challenge
021 705 346

How traffic engineering standards can break our cities «

It would not be too factitious to suggest that many traffic engineering standards seem to presume that land is free. It’s as is if there are dutch pixies at the bottom of the garden who are manufacturing land from the sea.

One example of such a standard is the concept of the “design vehicle”, which I will focus on for the remainder of this post. Of course there are many other examples of traffic engineering standards, such as minimum parking requirements, which have been discussed before on this blog and that also have hugely negative consequences. The reason I want to focus on the “design vehicle” concept is because it does not receive much attention. And also because it has a fundamental impact on so many things.

For those who are not familiar with the “design vehicle” concept let me briefly explain. The “design vehicle” is a phrase that typically describes the largest, heaviest (per axle), and/or least maneuverable vehicle that is expected to use a particular part of the road network. Naturally, the physical footprint required to accommodate this design vehicle subsequently defines most aspects of the physical road geometry, such as turning radii and pavement design. For this reason, the shape of our road networks is very much defined by the design vehicle that is chosen.

You can read up on some of the design vehicle standards recommended by the NZTA here. The design vehicle for the standard street is typically some form of medium rigid truck, such as what is commonly used to move furniture. I’ve illustrated the physical dimensions of this vehicle below.

Read more at: How traffic engineering standards can break our cities «

Students win national design award for 10sqm building | Scoop News

Students win national design award for 10sqm building

The design brief was simple – create a breakout space that didn’t require consent and incorporated sustainability, and now four Otago Polytechnic Design students have won the national Sustainable Habitat Construction (SHAC) Pop-up Challenge for their design of an innovative and efficient ten square metre building.

Studio56 was conceived by third-year Design students, Dean Griffiths, Alice Perry, Nina Daniels and Charlotte McKirdy, and was developed to provide a unique learning and collaboration environment for both students and staff, within Otago Polytechnic’s Living Campus – a vibrant community garden and a sustainable model of urban agriculture.

via Students win national design award for 10sqm building | Scoop News.

Students win national design award for 10sqm building | Scoop News

Where do you start a sustainable house?

So, you know you want a sustainable (healthy, efficient, affordable and desirable) home, but where do you start? I’ve covered the fundamentals  of what makes a good energy efficient home, but these are details. What’s the big picture? Where do you start a sustainable house?


Before getting too specific about your plan, here are some questions I recommend being able to answer:

  • Why are you renovating/building/remodelling/looking for a new home?
  • What are you most dissatisfied with at the moment?
  • How many people are you building for?
  • How much time are all these people actually going to spend in your home each day, each week, each month…?
  • What do you want your weekends to look like?
  • Describe your ‘perfect day’. Who are you with? Where are you? What are you doing?
  • Does you perfect day involve any of the following:
    • Mowing the lawn
    • Fixing a fence
    • Painting a fence
    • Cleaning windows
    • Cleaning a pool
    • Walking a dog
    • Vacuuming
    • Cleaning three bathrooms
    • Painting the house
    • Cleaning the house
    • Going on adventures with your family
    • Oiling a deck
    • Blowing/sweeping leaves
    • Gardening
    • Relaxing by the pool
    • Working a second job
    • Being at the beach
    • Harvesting vegetables and fruit from your own garden
    • Watching someone else do any of the above

What’s all this got to do with the location and layout of your dream home? A lot. Creating a better, sustainable place to live is about lifestyle. This is where you need to start.

When Natalie and I moved to Auckland our criteria for a place to live included:

  1. Walking distance to a primary school with a good reputation
  2. Walking distance to a train station and a train commute of 30 minutes or less
  3. At least three bedrooms, ideally four (Xavier, our third child had just been born, and we wanted to the option of a home office)


The next big question is about budget. There are two big questions here:

  1. How much do you want to pay each month to own and operate a healthy, safe home?
  2. How much money do have to design, consent, building and finish your project?

They’re both related. The more you borrow, the more your monthly expenses are going to be. The more you invest on good design, insulation and solar power, the less your monthly running costs are going to be.

As painful, boring or frustrating as it might be, it’s worth spending some time here. Most of the designers I speak to say that a client’s true budget is one of the hardest things to pin down. Knowing exactly how much money you’re wanting to spend and being honest about this upfront will save time money and disappointment by avoiding uneasy scope changes when you do start talking to a designer.

Read more at the excellent “Where do you start a sustainable house?.”

How to: Get resource consent

What’s it for?

A resource consent gives approval for things like the use or subdivision of land, the taking of water, the discharge of contaminants in water, soil or air, or the use or occupation of coastal space.

So you could say it’s to look after the resources that will support not only your home, but the area you live in.

How do you get it?

You write an application that says why your project falls within the bounds of the Resource Management Act and relevant local regulations and policies, and you pay a fee.

In practice, most people get someone else to do that for them and according to Dr Roger Blakeley (chief planning officer for Auckland Council) there is an “expectation that you would employ a professional” for this process.

But when I looked into it, it was going to cost between $10,000 and $15,000 to get someone to write our application, so I wrote it myself.

via How to: Get resource consent |

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.

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

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

Canon [2014-11]


Meet Canon, an environmentally friendly piece of architecture that gives a most unique portrayal of light. It’s a giant walk-in telescope, with the added aesthetic of providing its very own light show. Given our current economic predicament, it’s becoming more and more important that we respect the environment, thus Canon is constructed using recycled plastic and bottles, promoting the re-use of materials and less on the reliance on money. The theory behind the lens is rather quite simple, yet ingenious; light when shown upon the ‘lens’ is refracted in several directions – similar to the experience of being inside a kaleidoscope. When the lens are extended manually, the environment in which it is placed is instantly distorted, allowing the user to experience a different kind of world, a parallel world perhaps or even a unique abstract dimension, effectively superimposing its own personality which can be felt by anyone within its boundaries.


Cannon-2014-11-A3-small  Cannon3-2014-11-A3-small Canon-2014-11-image (3)-small Sky-2014-11-image-small