We are stoked to be featured in the ‘Trends’ issue of NZ House and Garden, November 2017. The ehaus House in Twizel designed and built by Hiberna sparked interest locally (as evident by the many visits from locals) as well as nationally. It is also performing beautifully: the current tenants didn’t even have any matches to light the fire when we turned up to take photographs one July morning. I wonder if they realised there is no other heating? Not your average Twizel bach, that’s for sure. Thanks to Alpine Images for the fabulous photos.
Watch our Pecha Kucha on our philosophy: How the most recent technology, combined with century-old construction techniques produces the best buildings – for our health, the planet and our souls: http://www.pechakucha.org/presentations/techno-mud-optimising-natural-building
The developer of this house in Wanaka wanted it to be a cut above what is generally available on the market.
They wanted a contemporary design with guaranteed low energy demand and superior environmental credentials.
We modelled the energy demand in PHPP and used the tool and sun studies in ArchiCAD to assess and mitigate its overheating risk. As is often the case in Wanaka, the views are to the west and this often leads designers to use large areas of west facing glazing, which then receives the brunt of the fierce, low afternoon sun. The design of this house balances the need for passive solar gain with the beautiful views of Mt Roy and Black Peak to the west. It is also moulded to the section, stepping up with the incline of the land.
The Homestar 7 rating was achieved through low energy design, Environmental Choice paints, finishes, linings and fittings, provision for recycling, composting and veggie gardens, xeriscaping (using native plants that require no irrigation once established), LED lighting, a Lifemark assessment, WELS rated (low flow) kitchen and bathroom fittings, FSC timber, and a waste and environmental policy for the contractor, amongst many other things that make up this very broad environmental tool. The house was rated in order for potential buyers to see an independent verification of its environmental credentials.
The Society would like to congratulate the applicant on their commitment to sustainable building. (Subdivision design board)
As with all our projects, we modelled the skillion roof in WUFI to check for moisture- transport issues. We used a membrane from Pro Clima to ensure that moisture does not accumulate in the skillion roof.
PVC windows were specified as a happy medium – the performance of timber windows but with minimal extra cost. A MAXRaft fully insulated slab ensures significantly reduced heat loss through the slab.
The developer is Red Bridge Developments. Thanks to them for seeing the value in both a higher quality build and also the value of the Homestar rating.
This holiday house was to be a base for its owners to explore the outdoors with their young family. They wanted something minimal, industrial, and inspired by south island high country huts. They wanted good connection to the outdoors, plenty of storage and overflow sleeping space for family and friends, hard-wearing durable finishes, a big mud room for wet and muddy gear and a warm comfortable efficient space. The Hiberna team worked with national Passive House experts eHaus to design and build a simple energy efficient house that was hard wearing but none the less outstanding in its performance and appearance.
One of the main challenges was the wind. Both for the design and on site during construction 155kmh gusts one night in january: Thats a force 2 hurricane. The site is in one of the highest wind zones in NZ and we needed significant extra structure LVL to cope with the high wind load. The design does include some sheltered outside sitting space to the east as the wind comes mostly from the north-west.
We kept the Auckland clients up-to date with an app called Trello. We uploaded photos and gave regular updates so that they could follow the progress of the build from a distance.
One of our favourite features is the mudroom. The corten steel gives industrial, solid feel of it. Ben’s acoustic control (to help reduce echo from hard surfaces) battened ceiling came out beautifully.
The Porcelanosa tiles reflect the texture of the corten.
Energy efficiency was very important to the clients. Twizel has a very extreme climate: Winter overnight lows can sometimes dip below -10C and highs in Summer are often above 30C. The clients approached eHaus because of their expertise and reputation for guaranteed warm and efficient houses built the PassivHaus way.
This home is healthy and comfortable to live in all year round while consuming minimal energy. Even in this extreme climate the only heating is a 5kW ‘Bionic’ wood burner, and even this is hardly used.
We designed the building envelope to have a continuous layer of insulation in this case SIP panels from NZSIP and a fully insulated raft foundation.
The solid timber high performance windows are locally made by Thermadura with triple glazing, they frame the stunning views with the right amount of external shading to protect from overheating in the summer.
The house passed an air tightness test using a blower door to make sure there are no leaks.
We achieved an air change rate of 0.42 ACH – well below the Passive House standard of 0.6
The final key is a heat recovery ventilation system that ensures fresh, dry air 24/7. We used the Passive House Planning Package (energy modelling software) which will ensures that the house will perform.
Many thanks to Alpine Image Company for their beautiful pictures!
This house, the dream of its energetic and creative owner, was intended to be both beautiful and highly energy efficient. The structure is a MaxRaft foundation, timber frame walls with R4, the windows are wooden frame triple glazed by Eurotech, the roof is timber frame with R6 and there is a MHRV ventilation system and a air-to-water heat pump. Airtightness is provided by Pro Clima intelligent membranes. The design was modelled in PHPP and details were modelled in Therm. It was a pleasure to help the client realise her unique vision for the house and her character shines out of every detail. Here are a few pictures, courtesy of Alpine Image Co. House design is by Hiberna Architecture. Built by Alternative Ventures Ltd, Queenstown.
If you are looking for a cost effective, off-the-shelf design without compromising quality or aesthetics, we have a selection of plans to choose from.
There are several reasons why people might choose to go with a non-custom design. You might need to get consent quickly, or you might need to take a fixed price to the bank. Sometimes it is easier to start with an existing plan and then modify it to better meet your needs.
These plans have been developed by us over the last few years, and have an emphasis of quality over quantity. The market is flooded with large mediocre homes; we are trying to reverse that trend: we think there is more long term value in quality buildings, built to last, that don’t break the budget because of their size. We don’t follow any trends apart from good, enduring design principles.
We agree with the Cactus Clothing Company when they say ‘wear in- not out’. For a building to last the centuries it needs to be loved; our buildings will need to be maintained, but unlike a lot of modern materials, earth, lime and timber can be maintained relatively easily and cheaply long-term. Build something you and your children can love, that will have the least negative impact on their planet.
All designs are strawbale with earth and lime plasters.
Contact us for prices and we can send indicative pricing. Final price depends on your choice of the optional features.
All plans feature the following:
- impressive R-values for all building elements
- natural, non-toxic, low impact, local materials wherever possible
- thermally isolated thermal mass
- a handcrafted feel
- Efficient water fittings
- LED lighting
- renewable heating
- open plan living
- passive solar design
- architecturally designed
…and can be customised with the following:
- solar PV
- custom built kitchens by artisan joiner
- earth floors
- composting toilets
- solar thermal water heating
- carports – attached or detached, depending on design
- rainwater harvesting
- grey water recycling
- triple glazed timber framed windows – not as expensive as you think!
- tadelakt bathroom finishes
- Exposed reclaimed woodwork
Those wanting to go the extra mile can upgrade these designs to Certified Passive House.
CLICK ON THE LINKS TO DOWNLOAD THE FULL BROCHURE.
The Moraine House is a 2 stage house, simple in form but exquisite in its detailing. The staged nature of the design allows for a cheaper initial project cost, but with the possibility of extending at a later date. The finished layout provides some sheltered outdoor space and plenty of covered exterior storage. It also has a good amount of internal storage for a modestly sized house and does not waste any space for circulation. A skylight lights up the laundry/storage space behind the living room. A large walk-in pantry is ideal for home produce. The step down between the lounge and the master bedroom provides separation and privacy.
PHPP analysis says this house will use approximately 8kWh/m2.yr – a certified Passive House must use no more than 15kWh/m2.yr… meeting that target easily! We would like to have some NZ data on the thermal properties of straw bales. The calculation of R 7.4 for the wall system is based on international data for straw bales.
The Pisa House is a 2 storey house, which is far from simple! This house is for those who enjoy little quirky details and a varied palette of materials. A tiny internal window peeps down from the upstairs landing into the kitchen; a window seat can double as an occasional bed; low windows upstairs will delight children. With concrete or earth floors and a rammed earth wall backing the wood burner, there are high levels of thermal mass. As with all our designs minimal thermal bridging reduces heat loss and good solar access maximises free heat. This is as big as we like to go; a whopping 140 square metres!
The Lindis cottage is our little baby – we live in a version of this house! While the plan is a compact 78 square metres we love its cozy feel. High ceilings downstairs make the open plan living area feel deceptively spacious, while the dormer windows allow for extra light and space upstairs. The spiral staircase is a unique and space-saving feature. Our initial Passive House Planning Package analysis shows this house coming in well below the Passive House threshold of 15kWh/m2.yr.
Here are some of the best TED talks on building green:
Catherine Mohr explains why there is no ‘ideal’ solution
there’s a thousand and one articles out there telling us how to make all these green trade-offs. And they are just as suspect in telling us to optimize these little things around the edges and missing the elephant in the living room.
Legend William McDonough, author of Cradle to Cradle explains what buildings would be like if designers took into account “all children, all species, for all time.”
It is unfortunate that the words humility and the word architect have not appeared in the same paragraph since The Fountainhead
Dan Phillips shows what is possible if you endeavour to use entirely reclaimed materials (assuming you have a lot of time, and a sense of humour!) His ability to reinvent waste objects into beautiful features is astounding.
Repetition creates pattern. If I have a hundred of these, a hundred of those, it doesn’t make any difference what these and those are. If I can repeat anything, I have the possibility of a pattern from hickory nuts and chicken eggs, shards of glass, branches. It doesn’t make any difference.
There are many reasons we like to build with straw bales: we have listed the main reasons we like straw bale as a construction material below. There is also a wealth of information available on straw bale building on line; we won’t repeat all that good information but we can point you in the right direction should you be interested in further reading.
- Durability – when built right this method of construction can be exceptionally durable. In New Zealand the bales in straw bale houses are generally not load bearing. Timber frames or posts carry the whole load of the roof or upper floors. In an earthquake situation the cracks that will inevitably appear in the earth or lime plastered walls (as with nearly any plaster system) can be repaired with out the need to replace whole wall sections. They are less likely to delaminate from the substrate due to the particularly good key of a furry straw bale. Fire resistance tests have also been performed on straw bale walls in both the US and Australia and they achieved a 90 minute rating (even unplastered bales smoulder rather than burn due to the lack of oxygen in a compressed bale). Simply put as long as the bales themselves are kept below about 80% humidity they will last indefinitely. As far as a tried and true cladding system nothing else even comes close to earth and lime.
- Thermal performance – whole wall system performance of R4.5 to R6 depending on bale thickness, wall plastering system and structural system. This compares to the R2.26 whole wall performance of a standard 90mm stud frame with R2.8 batts (under clause H1 of the NZ building code walls are required to only achieve R1.9-2.0 in non-solid construction)
- Aesthetics – The thickness of half a metre walls gives a very secure feel and the rounded, deep window plastered reveals reflect light deep into the interior particularly is lime washed, while creating a place to sit.
- Indoor environment – Using earth plasters as a base coat provides for exceptional humidity regulation 1.
- Environmental factors – where to start! As far as building materials go we can’t think of many more benign than straw bales. The earth plasters used in straw bale best practice are also extremely low impact, particularly if bales are sourced locally, which is usually the case. All buildings have a finite life, and a ‘grave’. When a straw bale building comes to the end of its life there a few far fewer materials that need to be disposed of in a landfill. The walls themselves can simply be returned to the soil from whence they came as they are 100% biodegradable. As long as all the other elements in a straw bale building have a similarly low thermal conductivity, a straw bale building will use far less energy, and therefore produce far less CO2 than a conventional building built to ‘code’. Fewer products need to be used in a straw bale building and earth, lime and straw are all non-toxic. In addition, both straw and timber sequester carbon when they are used as building material.2
- Economic factors – Straw is in itself a by-product, not the primary crop. Using more local materials in construction can only be a good thing for those involved in producing them.
There are also some common sense rules of thumb when it comes to straw bale building. We believe in a good hat (eaves) and boots (raised foundation) for bale walls and strongly caution against parapet walls. Permeable and softer plasters (lime or earth) should always be used in preference to relatively impermeable and more brittle (cement) plasters; we have checked our construction methods in our WUFI hygrothermal modelling software. Passive solar design is also a no brainer, and we take these principles into account wherever possible.
1 Evrard, A (2013) ‘Thermal inertia and moisture regulation of straw bale buildings with earth plasters’, PLEA2013 – 29th Conference, Sustainable Architecture for a Renewable Future, Munich, Germany 10-12 September 2013
2 Alcorn, A & Donn, M (2010) ‘Life Cycle Potential of Strawbale and Timber for Carbon Sequestration in House Construction’, Victoria University of Wellington
Galvin’s cottage in Cardrona was built in 1863 by Paddy Galvin, one of the original settlers of this early Gold Mining Town. Following a building survey by Heritage specialists Origin Consultants, Ben was called in to restore and re-plaster the exterior of this tiny historic cottage. The fragile earth walls had been damaged partly by the use of hard and brittle cement plasters. The hydraulic lime plaster will protect from the elements while allowing the structure the structure to ‘breathe’, essential for this type of construction; moisture must be allowed to permeate out of the structure. Ben patched the delicate earth walls with local clay-cob where necessary and then hand plastered the walls with NHL 3.5 hydraulic lime plaster. This, in addition to an annual coat of lime wash should help the cottage see out the century: its new life as a holiday ski cottage is just beginning.
Photos courtesy of Barry Hastings
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