At Our home
Living in a small space
One of the biggest problems with modern homes is that they are so big. Since the 1950’s house sizes have doubled while the population in each house has halved. Even if they designed to be energy efficient they still constitute a large area to be heated, cooled, lit cleaned, painted etc not to mention the embodied energy in the construction of a large house. For example the production of one brick produced one kilogram of carbon dioxide.
Another issue with big houses is their geographic footprint. Large single residences lead to sprawling suburbs requiring more roads and infrastructure, a greater distance between home and work, and a greater distance to transport food, power, water and waste. This also leads to the destruction of natural environments and a gradual loss of market gardens and farmland that once provided food for the people living in the new subdivisions that displaced them.
The kitchen and living area at #21 is about 40 square metres and there is a similar sixed room which functions as art studio for Tim, office for Shani and storage space. We used to sleep in the garden out the back in summer but have now converted a shed into a separate bedroom.
Our Living Room
The kitchen, dining and living room at Shimtani House is about 40m2 . We have put all the furniture on wheels so this space can be rearranged for running street meetings, hosting a dinner party, processing excess from the garden, or extracting honey from the bee hives etc.
If it gets too crowded we can open up the stacking sliders on the east to expand onto the verhandah. Or all the furniture can be moved outside onto the street for bigger parties or a film night!
Looking back, we wish we had designed the kitchen to commercial standards as it would have been useful to have a commercial kitchen on the street.
Our “Sleep and Escape” Room
We find with such an open house it is nice to have a space to escape to if you need it occasionally, so we converted a shed out the back into a bedroom.
Since we missed showering outside when we moved from The Painted Fish, ee have reconnected the old heritage listed outdoor dunny and added an alfresco shower to make our outdoor ensuite.
The bedroom has a classic passive solar design, about twice as long as it is wide, with good thermal mass, northfacing windows with pelmets and curtains, small ventilated louvers to the south, plenty of insulation, overhanging eves, a grape arbour to the north etc
You will notice there is a difference in the size of Tim and Shani’s wardrobes. Stefan from Handwerk made up our clothes storage to our own design. The rule is, if it doesn’t fit in you can’t have it.
You will notice our chook pen is right next door – we love waking up to the sound of the chooks, although we are grateful that the neighbourhood roster is a few houses away!
The whole house here is pretty well insulated. The roof of the back section of the house is made from econodeck – which is a sandwich of 200m polystyrene which has an r value of 5.2. The roof of the bedroom and front of the house have aircell and batts with an r value of about R4 in the bedroom and R3 in the front of the house.
The walls have custom orb on the outside (which reflects some heat andcools down quickly in summer). Under this is a 25mm batton which creates the airgap required for the next layer (aircell) to work at its best. Under the aircell is timber framing fitted with R2 batts and then the internal gyrock lining. Tim thinks the whole thing would be rated at about R4. The bedroom has similar wall insulation, but the living room is a bit lighter as there are no batts in the walls.
The more Tim builds the more insulation he uses!
We were really happy with the effect of spraying the roof at The Painted Fish with a special reflective white paint. Tim did read a few articles however that suggested any white acrylic paint would have the same effect so when we replaced the roof at Shimtani we used a white colour bond.
While it is better much than a black roof, it seems to have much less of a cooling effect than the reflective paint. Mind you, it is much better than the day we removed the old roofing (leaving only the internal ceilings intact) It was that Boxing Day a few years aga when it was 43 degrees – well it was over 50 degrees inside!
Now with white tin, air cell and batts it is pretty comfortable on all but the hottest days and even then cools down almost instantly when the south westerly hits!
The bedroom and work room at Shimtani have good thermal mass in the floor. This, coupled with good solar exposure to the north works to moderate the temperature, keeping it cooler in summer and warmer in winter.
Ideally, as well as the slab floors in the bedroom and office we could have used bricks for the interior walls to increase the thermal mass in these rooms. However, as brick has a high embodied energy and a high carbon cost, we decided to use gyprock instead. If we find we need more thermal mass we may try fitting a narrow water tank internally to increase the mass.
Windows for ventilation
To get light and heat into the house in winter we have installed long large north facing windows. As is often the case in suburban settings the proximity of trees, fences and neighbouring buildings limits the availability of winter sun, but most of the time these windows work well – we never need lighting indoors during the day!
These windows are designed with some opaque glass for privacy. They allow the option of lowering just the top half to assist with ventilation in summer.
Together with smaller louvered or side hung windows on the south of the house, these provide great summer ventilation. Because the southern windows are smaller and lower than the windows on the north, they work together to encourage the cooling south west air into the house and the warmer air up and out to the north.
We have also installed two sets of vents directly behind the fridge. We open these in summer to vent the heat from the fridge outside and close them in winter to keep this heat inside.
Windows are tricky really – you need them for light and heat in winter and ventilation and cooling in summer . . . . but as far as insulation goes they are like having a big hole in your wall.
Eastern sliding glass doors The big area of glass we have facing east is not really ideal but in this case we installed them as a way of opening the house out onto the verandah, out onto the garden and then out into the street – expanding our living space, welcoming community and increasing air flow on summer evenings.
The verandah gives good shade most of the day in summer. Over the really hot months we plant climbing beans and run them up fishing wire to the top of the verandah. This creates a cooling green layer of vertical shade that protects us from the early morning sun, and beans to eat!
We also used a “low e” glass in this eastern section. It retains more heat in winter and allows less to enter in summer. While this does make a difference it is still probably not adequate and hence this winter we added curtains with pelmets.
Southern louver and side hung sash windows For controlling heat in these smaller windows we found it easiest, cheapest and very effective to cut out sections of air cell and press them in to the window frames.
North facing windows We spent a great deal of time thinking about what to do with these windows. Although they are not really beautiful, roller shutters are a really good way to insulate your windows, especially where you don’t have wall space outside for shutters or inside for curtains. Tim describes Perth as having about an 8/4 month split (8 months hot and 4 months cool) so for most of the year are wanting to keep hot air out of your house. For this reason insulation on the outside is highly effective as it stops the sun before it gets to the glass.
We have also planted some deciduous vines (Virginia creepers) along the north side of the house and these will eventually form an “organic solar pergola”. We even have dreams of a solarium to capture more winter sun for heating, growing seedlings and drying clothes.
At Shimtani we organised Solar Shop to instal a 1.4 kilowatt hybrid photovoltaic system. A hybrid system is a mixture of monocrstaline and thin film panels . We chose hybrid panels as we have a relatively small north facing roof and they have a high output per m2. They also have a relatively low energy payback period.
This system produces about 8kwh of electricity per day averaged over the year – which is enough to run our household four times over. Our thinking is that as the 1 kilowatt system at The Painted Fish doesn’t produce enough power to cover its use we would put in a larger system here to compensate. This means that overall we are electric energy neutral or slightly net producers. We decided not the sell our REC’s, which means any power we make is in addition to the 20% renewables target set by the government for 2020.
At the moment 37% of houses in Hulbert Street have photovoltaic panels, and another two homes were told it was not worth while installing them due to shade or roof angles. How is your street going?
We have not installed solar hot water here yet, but we have purchased and instantaneous gas system that is compatible with solar systems. Tim wants to experiment with a home made black poly pipe system – come and see it at next year’s Fiesta!
Energy Efficient Appliances
When we first moved into # 21 our daily energy use was about 2kw hours a day (we only had a small fridge!) but we moved Shani’s “energy efficient” but large fridge in our daily power rose to 4 kilowatt hours. So basically Shani’s fridge used more power on its own than the entire house (including the smaller fridge!)
After a bit of research we sold the large fridge to a big family and bought a fridge that uses about 330 w daily and a chest freezer that uses about 700 w daily. This fridge is larger than we really need but we wanted the chest freezer – we are working on offsetting the energy use by preserving excess garden produce that cannot easily be sun dried! These appliances are made by Vest Frost and we bought them from WA Solar Supplies.
The lights at #21 are all compact flouros or LEDs so our lighting use is small. We don’t own a TV – plasma or otherwise!
Any supplementary heating we use in winter comes from a small gas heater. Tim is planning a north facing solarium like at The Painted Fish so hopefully by the Fiesta 2011 we will be confident enough to sell the heater – we didn’t use it at all last winter. And when it’s hot we use fans for cooling, open the windows when the sea breeze comes or go to the beach!
Our cooking is gas as well (except for the solar oven we use in summer and that is made out of a cardboard box!)
You will notice all the power points at #21 are half way up the wall (like they used to be in the old days!) We did this so it is easier to turn off appliances that are not being used and it works really well
The submersible pump in our rainwater tanks is pretty power hungry but as our domestic use is only about 40,000 litres of water annually that doesn’t push our power use up too much.
And the results? – we are now proud to say we are back to about 2 kw hours per day!
Shani’s friend Jacinta was the first person she knew who had made a solar oven. She found a fabulous website which described how to make a solar oven in an hour, and given their stove had just stopped working, she thought she would give it a try. Shani talked Tim into making one soon after – really it is two boxes with large amounts of insulation in between. We used old insulation and silver tape to line the oven. You add a rack for the pot to sit on and a glass cover and away you go!
And what fun it is – we have made casseroles, cooked meat, cakes – just about anything you would do in your oven. We find the food tastes quite different – much more flavoursome. During the hot summer days, Shani found if she put a casserole on in the morning it was ready for lunch – and the house didn’t need to get hot!
Tim has plans for a new solar oven using the door from an old oven he found on the side of the road- roll on summer!
If you would like to make your own solar oven check out: http://www.starship-enterprises.net/Solar%20Oven/
Shani found that once she had some success in the garden, she then had a need to preserve the excess. We began by sun drying – on racks in an old wheelbarrow painted black, on the dashboard of the ute, and on an old screen door. Shani has successfully dried tomatoes, peaches, plums, corn, beetroot and even carrots from the garden.
Her friend Amy was given an electric fowlers vacola kit for Christmas and soon a healthy canning competition ensued. Shani found an old stove top kit from the quokka, and the search for bottles began. Soon the kitchen cupboards had to be extended to store her produce. Shani’s goal has been to not have to buy tomatoes and she has been achieving this for two years now.
Shani also makes her own jams and ketchup, and great lemon cordial. She loves always having preserves for gifts on hand, and between what is in the pantry and what is in the garden she rarely has to go to the shops.
Reducing our Waste
There are really two stages to dealing with household waste.
The simplest of these is figuring out how to put the right stuff in the right bin. We are very lucky – our local Council’s recycling program means that about 70% of our waste is recycled in some way. In reality our two street bins are both recycle bins – one (green topped) for compostable material, which is made into high grade compost for gardens, and one (yellow top) for recyclables and other “dry” material. The yellow topped bin’s contents are sorted and mostly recycled, with the rest sent to land fill.
Shani uses a simple bench top system for her organic waste – one bucket for the chooks, one for the compost and one for the council green bin. And under the sink is a drawer for our yellow topped council bin, plastic bags, reusuable shopping bags, newspaper and a tin for batteries.
But sorting is just part of the story! We have concentrated on three ways to reduce our waste
First, we think about the packaging around what we buy. Fremantle’s Sustainability Officer Alex Hyndman recently challenged a group of friends to go plastic free for a month. It is a real eye opener to realise how much plastic packaging and junk we usually buy, particularly when you realise a plastic bag will take hundreds of years to break down.
Second, we think about whether we need to buy stuff, regardless of its packaging. Could you borrow it, make it, fix it, buy it second hand, share it with a neighbour? And do we really need it at all? Shani is on her second year of a “No New Clothes” pledge. She finds it very liberating to not feel the need to look in clothing shops and she is much more creative about what she makes, or buys second hand. And her wardrobe is a set size – so if she buys something, she has to give something away!
Third if we do decide to buy something we try to get something that will last, be repairable, or be recyclable at the end of its life. This explains Shani’s recent purchase of a Thermomix – she plans to still be using it when she is 80, unlike her blender which blew up after only five years!
Water Tanks? They’re Underground!
Because we have such a small block here at #21 (about 210m2), we decided to put our rainwater tanks underground. Although the cost was a bit higher, we decided as we could build vegie beds over the top of them, it was a bit like buying your front yard back. We used two 2 X 2 soak well liners in tandem giving us two tanks of approximately 7000 litres each (2400 by 1800) The tanks are lined with a pvc liner.
It was pretty tricky installing these tanks due to the restricted space. The first half of a soak well liner put level on the ground. Then the sand was removed from inside the tank until the tank subsided into the ground. Then the second soak well liner half was stacked on top and the process was repeated. We are really grateful to our bobcat driver- we ‘reckon he could do up his shoelaces with his excavator.
The water is collected from the front half of the roof, flows through a leaf eater and a first flush diverter similar to the system at The Painted Fish, and then into the tanks. Once collected in the tanks the water is then pumped into the house via a submersible pump, filtered through an inline filter. We use this water for all our household water needs – in the garden, kitchen and bathroom.
The sandy soil in this area is ideally suited for underground tanks as it is quite stable and easy digging (unless of course you hit limestone!)