Violet Town EcoLiving Project

Eco Buildings, food and forestry in a small country town

2011-07-21T20:11:00.000-07:00

Walking tours and site visits

Groups can arrange to visit the retrofitted community buildings to see the works described on this blog. We also sometimes conduct village walking tours, which include the retrofitted community buildings, wood-fired oven, community forest, energy efficient homes, and Murrnong Permaculture Farm.

To discuss a possible group visit, contact David Arnold 03 5798 1679, arnold.vt@gmail.com, or Robin Landvogt, 03 5798 1735, rplandvogt@gmail.com [Tours of Murrnong Permaculture Farm are held more often, contact David directly about these.] Below are the details of a previous village walking tour.

Walking Tour, 11am to 3pm, Sunday August 21st 2011

The tour advertised as part of the Festival of Design on Sunday 24th July has booked out. This event on Sunday 21st August has the same format. Bookings/ enquiries to arnold.vt@gmail.com, ph 03 5798 1679

Come for a tour of Violet Town sustainability initiatives with local permaculture designer and teacher David Arnold, and see how much even a small rural community can achieve in just a few years.

Visit the energy efficiency retrofit of the community buildings, a volunteer-driven creek restoration project, two energy efficient houses, the Violet Town Community Forest, and Murrnong Permaculture Farm, all by easy walking from the centre of town and the train station. For each element of the tour, David, and the householders visited, will discuss how they interact with their house/ building/ forest/farm to achieve energy efficiency, productivity, and a high standard of amenity. A lunch of local produce is included with the tour.

To live more sustainably we need to observe and interact with our environment. We need to actively manage our own houses, our shared public buildings, our public open spaces, our food supply, and in Violet Town they are even providing for their own forestry products.

The design strategies discussed all require some active management, are evolving and changing over time, and are responsive to changing circumstances.

Tour starts at Violet Town Community Complex, 37 Cowslip St, Violet Town, 11am.

For train travellers we will fit in with the Vline service that arrives at 11.09, and have you back in time to catch the 2.41.

$30/ adults, $15/ children Bookings/ enquiries to arnold.vt@gmail.com, 03 5798 1679
Presented by Violet Town Action Group.

Wood-fired Oven

2011-05-23T05:53:00.000-07:00

The EcoLiving project undertook to build this wood-fired oven within the area used by the Violet Town Market as a community asset, and to promote local natural food and local fuel wood from sustainable forestry. The oven was built by a tremendous volunteer effort lead by Neil Garrett, with notable contributions from Bill Wood, Mick MacLaughlin and many others, and co-ordination by Warwick Paton.

Neil Garrett, architect and builder of the oven, celebrating completion, 26th May 2011 photo: Sandy Garrett

Sandy Garrett and Sue Paton serving pizzas at the May 2011 market, while Neil takes care of the baking. Photo: Paula Ajuria
The weekend before this market Thomas Moritz of Boonderoo Farm bakery lead a workshop on operating the oven, and making pizzas.

Thomas at the workshop. No wonder the oven and pizzas attract a lot of interest at the market - the oven looks good, and the pizzas inside with the fire look so good. They cook and taste as good as they look. Photo: Paula Ajuria
For baking pizzas a fire is kept at the rear of the oven, and the pizzas cook with conducted heat from the base bricks through the pizza tray, radiant heat from the bricks in the vaulted oven ceiling, and convected heat from the air circulating through the oven. The only way into or out of the oven is through that doorway - the old cast iron door and frame was salvaged from the old scotch oven that baked the bread for the village until 1969. This new oven is highly efficient with well insulated thermal mass. It can stay hot and keep baking for a day after firing it overnight with just a barrow load or two of wood. The Violet Town Lions Club have been supplying the wood for the oven.
Workshop participant Paula Ajuria writes... "First time making pizzas in the oven was a success with many participants at the workshop taking turns at shuttling pizzas in and out of the oven on the pizza shovel.
As a local farmer and baker, Thomas believes in community self-reliance and firmly promotes local and seasonal products for making pizzas. He pointed out that there is no need to offer some of the familiar pizza combinations such as ham and pineapple as we can top our pizzas with a great variety of foods from this area, and as he pointed out, 'we can’t grow pineapples here!'
Neil’s choice of glazed bricks (2nds bricks bought cheap from Euroa Clay Products) was influenced by his recent travels to Spain, Portugal and Morocco. The oven's bricks are practical as they stay clean and its bright colors integrate harmoniously as a feature in the area next to the children's playground."

Kaye Bradshaw (chair) and Sarah Hamill (co-ordinator) of the Violet Town Community House selling pizzas at the market. Photo: Paula Ajuria
Violet Town Community House has taken on the management of the oven. To book the oven for private functions or to enquire about community group use contact Sarah on 5798 1288 or violettowncommunityhouse[at]gmail.com

During the workshop Paula learnt from Thomas that many people who are gluten intolerant - an increasingly common condition - can safely eat sour dough bread. Sour dough baking uses a beneficial brew of wild yeasts and bacteria that ferment the flour, and which break down the gluten. This was exciting news for Paula as she is gluten intolerant and had not eaten wheat flour for 10 years. She did some research, made and ate some sour dough bread with no ill effect, and wrote this summary of her research.
"Only a retained heat wood fired oven gives you that unique flavour that can not be reproduced in a normal kitchen oven and only sourdough brings out the taste of bread as it was known originally. The oldest and most original form of leavened bread originated, like wood fire ovens, in Egypt around 3000 years ago.
Sourdough remained the usual form of leavening down into the European Middle Ages until being replaced by barm from the beer brewing process, and then later purpose-cultured baker's yeast. Some bakers have kept using the sour dough process.

Health benefits of sour dough:
All grains contain phytic acid (an organic acid in which phosphorous is bound) in the outer layer or bran. Untreated phytic acid can combine with calcium, magnesium, copper, iron and especially zinc in the intestinal tract and block their absorption. This is why a diet high in unfermented whole grains may lead to serious mineral deficiencies and bone loss.
Soaking allows enzymes, lactobacilli and other helpful organisms to break down and neutralise phytic acid. As little as seven hours of soaking in warm acidulated water (sour dough leaven) will neutralise a large portion of phytic acid in grains.
Soaking in warm water also neutralises enzyme inhibitors, present in all seeds, and encourages the production of numerous beneficial enzymes. The action of these enzymes also increases the amount of many vitamins, especially B vitamins.
And if you are gluten intolerant:
During the process of soaking and fermenting, gluten and other difficult-to-digest proteins are partially broken down into simpler components that are more readily available for absorption. If the fermentation process continues for long enough and the requisite bacteria are present then most if not all of the gluten may be broken down. This would explain why some gluten-intolerant people can digest sourdough bread without any symptoms of gluten allergy." Paula Ajuria
Reference: Nourishing Traditions by Sally Fallon

The completed oven. photo: Sandy Garrett

Catch and Store Water

2010-06-20T20:38:00.000-07:00

Regulations that require the water supply to public buildings to be chlorinated, combined with the relatively low water use of these buildings, made the cost/benefit of plumbing these buildings in to their own tank supply to be marginal. However tanks have been installed to both buildings, at present for outside water use only.

18 000 litre tank at east end of Hall, showing first flush water diverter at left. The first flush of water off the roof washes it, fills this diverter, then cleaner water is allowed to flow into the tank. Diverter empties between rain events. Water from this tank is used to irrigate the entry courtyard garden, and to operate the misting cooling system.

Tanks being delivered. The black t-shirt says "I do whatever the voices in my head tell me to do." : ) Delivering tanks is a good start.

Tanks at early childhood centre. The small tank at right is for the children's use, to fill little buckets for summer play in the sandpit. When it runs out, the children can be prompted to think about where water comes from, how it can run out, etc. Modern house design and reticulated services can leave young people ignorant of where supply comes from, of what is behind the tap or the switch on the wall.

David Arnold

Use electricity wisely

2010-06-05T19:26:00.000-07:00

A very high quality and precious resource
But isn't electricity cheap, and don't we have 300 years of coal supply in the Latrobe Valley? Yes, it does come relatively cheaply to the householder, while the digging up and infrastructure maintenance to transmit it around the state is still being subsidised by cheap oil. As the coal resource becomes deeper and more difficult to extract, and extraction costs increase with fuel costs, we can expect electricity to become substantially more expensive. Electricity production from brown coal already creates enormous environmental cost with CO2 emissions and sulphur contamination over Gippsland.

Yallourn and Hazelwood power stations photo: Brian Yap

Solar panels, wind farms, and hydro in Victoria will never replace the quantity of power that the Latrobe Valley produces. We will simply have to do better with less.

For these buildings electricity operates the computers, internet, telephone, data projector for presentations and movies, photovoltaic display monitor, small fan and electronic controller for the roof mounted solar collector, ceiling fans, lighting, and power tools for maintenance and the retrofit. All of these are 'small and clever' uses of electricity, where relatively small amounts of this high quality energy are used to produce great benefit.

Electricity is not so well used for space heating, 'climate control' cooling, or hot water. These 'big and dumb' tasks can be better done by simpler energy sources such as sunlight (solar), firewood, solid shade, and the transpiring green leaf for cooling.
Reverse cycle heat pump air conditioners
Thoughtful use of the existing reverse cycle air conditioners in the smaller public rooms, for public events, with many people benefiting, is reasonably energy efficient. See below about combining these with the ceiling fans.

Visiting TAFE sustainability assessors group in the Supper Room, June 2010. Reverse cycle heat pump air conditioning for space heating is supplemented by warm sunlight through the roof windows, and the warmth is gently circulated by the ceiling fans. Moderate amounts of electricity for space heating is reasonably efficient when there are many people using the space.

There are twelve existing reverse cycle air conditioners across the Community Complex and Early Childhood Centre. To make sure these are at least turned off when the building is empty, we installed 2hr timer switches on all of them., and also on a very occasionally used little electric hot water unit in the meeting room kitchenette.

Timer switch on Supper Room air conditioner, with note encouraging users to think before using.

Air conditioner compressors on the WNW facing wall of the Early Childhood Centre. Placement of the compressors in a hot exposed position can increase power usage by 20%. We need these trees to grow, and more trees planted, to shade them. These air conditioners can use 18.4kW, while the maximum power that the $20 000 worth of photovoltaic panels on the roof can produce is 4.86kW.
The allure of 'climate control' with indoor air conditioning is understandable, but unfortunate as domestic energy use for heating and cooling generates massive CO2 emissions which are thought to be de-stabilising our climate. The more we seek 'climate control' the more our planet's climate goes out of control!

The permaculture principle of apply self-regulation and accept feedback is relevant here, as is the ethic of fair share.

Creating cool pleasant outdoor spaces can reduce our reliance on air conditioning. Here Graeme Dosser, Brian Mirtschin and Henry from Benalla Woodworkers are sitting on one of the two new seats they made for the internal courtyard that the Library and RSL have shared access to. With overhead vines and walls all around, this courtyard will be a great place for summer outdoor reading, or an RSL barbeque.
General principles of natural cooling

Our skin is a natural evaporative cooler. Studies have shown that gentle air flow over our skin can make us feel 5 degrees cooler, even though there there has been no actual change in temperature. This does not require obvious sweating. In our often hot dry climate in NE Victoria we can be constantly evaporating moisture from our skin, and helping to cool ourselves, without ever actually feeling sweaty.
This kind of temperature regulation is what human skin has evolved to do. Being 'acclimatised' refers partly to our skin's fitness at regulating temperature. Unfortunately with common use of air conditioning many of us are acclimatised only to temperatures between about 21 and 28 deg C. We need to regain our capacity to cope with a greater range of temperature.
Ceiling fans

We can use breezes, draughts, and ceiling fans to generate air movement. Even if an air conditioner is used, it is more energy efficient and just as comfortable to set the unit to a slightly higher temperature, so it doesn't have to work so hard, and run ceiling fans to move the air over your body. The relatively big ceiling fans generate air movement more efficiently and quietly than the fan in the air conditioner.

Ceiling fan installed in the kitchen. This can also be used in winter, on low, to move heat down, and to push excess heat from the kitchen out into the supper room. Warm beam of winter sunlight from the roof window can be seen on wall behind.
The big fan
Just as domestic ceiling fans can move more air more efficiently than the smaller air conditioner fans, for big spaces one big fan can be much more efficient than lots of smaller ceiling fans.

Macro-Air 6m diameter fan in the Hall. This operates on 250W, turns slowly, and moves more air with less noisy turbulence than 9 x 90W domestic ceiling fans. The controller, mounted in the foyer switchboard cupboard, creates three phase power to operate it. The fan was described as 'silent' or as noise not being a problem, but there is a high frequency background noise emitted by the controller and fan when in use. Many people do not notice or are not bothered by this noise, but some are. At a busy event with background noise no-one would hear it. Mostly this fan has been very well received and appreciated.
The big fridge
The big 2 door fridge in the kitchen draws between 580 and 830W, and runs hard and noisily. It is a terrific asset when catering for occasional events of 100, or even 30, people. In 2008 it used about 2.4MW/hrs of power, creating 3.2 tonnes of greenhouse gas production, costing about $230 on the power bill, and for most of that time was either empty or had one carton of milk in it for most of that time.

The big fridge is now only turned on when needed. The little bar fridge runs all the time, and uses 204 kW/hrs per year, less than 1/10th of the power that the big fridge was using! The $309 spent on this new little fridge was cost effective.

David Arnold

Control Vents and Draughts

2010-06-04T23:13:00.000-07:00

Existing Ventilation and Draughts
Many rooms in the community complex building leaked like a sieve. In the 1970's, when this building was constructed, regulations for buildings where public gatherings are held required very high levels of ventilation, including permanently open vents. These regulations were changed in the 1980's, but they left us with a Main Hall and other rooms that were excessively well ventilated. Some of these vents just needed to be covered with insulation and closed off, while others could be useful sometimes.
Ridge Vent in Main Hall
The main hall was built with a permanently open ridge vent that runs the full length of the building - 7m along the top of the stage, and for 18m above the hall.

Trevor Northey setting up for the big fan in Hall, with stage behind. The ridge vent runs right along the top of the space. It is ideally placed in some conditions for releasing excess heat inside, but made it very difficult to warm the space in winter. There are stories of people dancing in their overcoats. The two pairs of double doors to the foyer and courtyard can be seen at left.

As each person's body heat can emit 500W of heat, a hall full of 200 people generates - just from the people - 100kW of heat. In summer this needs to be vented, but in winter the body heat alone can warm the room, provided most of the heat can be retained in the room.

Another aspect of the building design makes the ridge vent potentially very functional, in some conditions. The main entry to the Hall is through the well sited entry courtyard, open only to the south, then through 2 lots of pairs of double doors, through the foyer into the Hall. In some wind conditions, we expect be able to use the ridge vent and open-able high windows to act as a thermal chimney, venting heat and drawing cooler air in from the south courtyard.

Graphic, not of this building, showing the general principle of a 'thermal chimney', using high vents to release hot air, and drawing in cooler air, usually from a shaded area to the south.

View of south entry courtyard, being re-landscaped with new pergola to carry a canopy of grapevines for shading and transpiration cooling. Entry doors to foyer and hall can be seen behind. Misting sprays on this pergola will further cool the air in this space, when cool air is needed for a public event.

Close-able covers for the ridge vent
We needed to a means to control the operation of the ridge vent, so we can close it in winter. Local engineer and inventor Murray Ellis devised a mechanism for this, and will be installing these close-able covers in June 2010 with Trevor Northey.

More thermal chimneys
The roof windows above the kitchen and supper room can vent heat, and on occasion draw cooler air from the entry courtyard space adjacent to those rooms.

Kitchen roof window opened to vent heat, and possibly help to draw cool air into the supper room from the entry courtyard.

Double hung windows are a traditional design that can help to create natural air circulation, with hotter air exiting above and cooler air coming in below.

Tall double hung windows in the Kindergarten, with new flyscreens behind. New heavier safety glass in these windows had made these too heavy for their spring balances, and they were out of use.

Trevor Northey was able to make these windows work again by counterbalancing the top and bottom windows with this little pulley arrangement, so they now work well.

Operating a building space for passive or assisted ventilation
This requires building users to think about opportunities to work with breezes, or a cool air source and high vents, before taking the easy but energy expensive option of putting on an air conditioner if there is one available. With natural ventilation there are benefits of fresh air, already partially filtered by the courtyard space.

Window flyscreens and flywire doors installed at the Community House to encourage use of natural ventilation.

Courtyard air access to supper room
One of many little signs around the building to encourage thoughtful use.

David Arnold

Use Energy from the Sun

2010-06-04T18:18:00.000-07:00

We aim to make as much use as possible of the sun energy that falls on the building each day, and to deflect unwanted heat. This reduces the amount of electricity and gas that need to be brought in from outside, which come at a financial and environmental cost.

We use the sun to generate electricity, to make hot water, and to warm the inside of the building in winter, including by growing trees for firewood.

North Windows in Main Hall

These windows were an appropriate part of the original building design. Blackout curtains will be removed and overgrown Photinia bushes have been cut back so that the windows can again function as solar collectors for winter warmth into the Hall. [The Photinia bushes are dense, attractive, hardy, soften the outside face of the wall, and the work of cutting the tops back can be repaid by a valuable animal fodder yield from the branches.]

North face of Hall, May 2010. Photinia bushes growing back across the high windows, need routine trimming, ideally in Autumn, which is usually a time of feed shortage so the branch fodder can be well used. Blinds across windows at right hand end stage need to be raised when winter heat gain is desired.

Roof Windows

The Kitchen and Supper Room had old skylights in the ceiling/roof which did not seal against draughts, were not insulated, and allowed the heat of the summer sun to come straight through into the room. Modern upgrades to these skylights were investigated, which are better sealed, insulated, and deflect summer sun to some extent. However the available options all came with disadvantages to do with lack of durability, relative expense for small benefit, complicated moving parts, and the unavoidable compromise for flat or low angle skylights between desirable light and unwanted heat gain.

We decided to replace the skylights with substantial North facing vertical roof windows. These have the advantage being designed with an appropriate eave, so that unwanted high angle summer sun is excluded while the low angle winter sun can shine directly in below the eave and warm the room. This is the 'magic' of solar design using north facing glass and appropriate window/eave relationship. The eave is matched to the height of the window to control when in Spring the sun is excluded for the Summer, and when in Autumn the sun is allowed to shine in for the Winter.

Supper room roof window, midday on 14^th May, showing the low angle winter sun shining into the room below. The triangular piece of flashing at the ends is to keep out early morning sun in summer. The eave had to be larger than normal, as the building (and windows) are not oriented perfectly north, but face NNE. Morning sun in summer would have come in under a smaller eave. This was designed partly in theory, with a scale drawing, and partly also just by modelling different eave positions on-site on a summer's day.

These roof windows are excellent big skylights, giving good natural lighting to the rooms without need for additional daytime lighting. Andrew Otto Woodworks used Australian hardwood for the window frames, to avoid having to use large amounts of energy expensive aluminium – sometimes described as 'congealed electricity'. We feared that future maintenance of this public building could overlook painting the outside of these window frames, since they are out of sight from ground level, so Andrew flashed the entire outside frame with lightweight metal flashing, sealed to exclude water with silicone.

Double glazed timber roof window fully flashed with lightweight metal flashing, sealed to exclude water with silicone beading.

These open-able and fly screened roof windows also serve as valuable high vents, operated by a remote switch. (Manual winding operators, through installed cables, could have been a good option if they were more easily available)

Overall the construction of the roof windows was more expensive than simply upgrading the skylights to modern energy efficient ones, but the big roof windows have so many additional benefits that they give much more value for money. Their construction did depend on having access to an experienced and adaptable carpenter such as Trevor Northey, who was willing to solve problems and custom build. And the flat roof/ceiling framework was reasonably easily adapted to carry the roof window frames, with existing steel beams there to carry it.

Supper room roof window framing, showing the existing steel frame (painted light green) that was available to carry the newly framed roof. This new framing is no heavier than the roof tht it replaced, and the new heavy double glazed windows are carried by the wall at left.

Wood heating

How is wood heating related to using energy from the sun? Because plants are our fundamental solar converters. The sun is the main driver of planetary life systems. It is the energy source that powers weather, including rain, and plant growth.

So we can think of fuel wood as embodied solar energy, provided
it is harvested locally, otherwise it might be embodied transport fuel
it is grown and harvested sustainably, preferably through forest or woodland management that results in a net increase of stored carbon, biodiversity and habitat values, and overall biological productivity, while also giving a yield of wood products along the way.

In 1996 we planted the Violet Town Community Forest on unused land at Shadforth Reserve in Shiffner St. This is designed to integrate sustainable forestry with amenity/ recreation use and biodiversity values. The high value forestry products will be long term sawlogs and durable poles for building. As the forest develops it can benefit from thinning and management, with a continual yield of fire wood.

This stand of naturally regenerated Grey Box at the Community Forest is approximately 20 years old. It already has construction quality poles available, which could be 'pruned' from multi-stemmed trees as in the foreground. 'Thinning' – removal/harvesting of some trees – from the dense parts of the stand would allow selected trees to grow on, and fast track the evolution to a mixed age, multi-level and biodiverse stand with more of the qualities of an old growth forest or woodland.

Ken Whyte, plumber, installing the flue for the wood heater at the Community House. Dec 2009

Jan Howe and Pete enjoying the new wood heater at the Community House. May 2010. This room had no other heating, and only small solar gain through its mostly shaded north window, and west window at back left where the heat reflective blind would more usefully be up in winter. A Nectre 'Baker's Oven' was chosen to make better use of the heat for a cooktop, and for baking, in Community House programs.

Roof Mounted Solar Collectors

In the Meeting Room, and Day Care room at the Early Childhood Centre, we installed 'Sola-Mate' solar collectors, for warmth and cooling. These are another option for spaces that cannot catch the sun's warmth through north facing windows. An electronic controller directs a small electric fan to blow warm air into the room from a roof mounted solar panel, when needed to warm the room.

Sola-mate panel above meeting room, May 2010.

The solar panel also sheds heat to the night sky much more quickly than the interior of the room can, so on hot summer nights the controller can direct the fan to blow cooler air from the panel into the room.

The incoming air is fresh, and is pushed though a filter [changed every 12 – 18 months] which removes pollen and dust.

Solar hot water

The Community Complex building uses very little hot water, mainly for occasional kitchen use. It was appropriate to keep the existing and fairly new instantaneous gas hot water service for this occasional use. Instantaneous units only use energy when hot water is used, which is efficient for this situation.

However there was a 40m hot water pipe to the hand basins in the Men's toilets, and a 20m pipe run to the Women's toilet handbasin. This was very inefficient. People washing their hands would turn on the hot tap, wash their hands, and turn it off again long before any hot water would reach their basin through the long pipe run. Hot water would be left in the pipe to cool before the next person washed their hands, and the energy used to heat that water was wasted. So we simply disconnected the hot taps in these toilets.

The Early Childhood Centre had an electric storage hot water service. This consumed about 8kWhrs/day when hot water was used, and still consumed about 6kWhrs/ day when no water was used! This is apparently fairly standard for electric hot water units, so we replaced this with a gas boosted solar unit. We chose evacuated tube solar collectors for their greater efficiency in winter – it is easy for solar collectors to make hot water in summer, even normal garden hose can do it. And again, the instantaneous gas booster only uses gas when hot water is used.

Three types of manufactured solar collectors on the WNW facing Early Childhood Centre roof. Evacuated tubes for solar hot water in foreground, photovoltaic panels for electricity at right rear, and at the left rear, slightly shaded in the late afternoon, is the sola-mate panel for heating and cooling.

Solar electricity

In early March 2010 Clear Solar put 4.86kW of solar panels on the Main Hall roof, and another 4.86kW on the Early Childhood Centre [ECC] roof. A west facing area of the ECC was the least shaded space, so these panels were put on frames.

Matt and David from Clear Solar installing the panels on frames on the west facing Early Childhood Centre roof.

The inverters were installed in May 2010. The installation does not have battery storage, but is grid interactive. When the sun shines power is supplied to the grid, and recorded as credit on the meter. When the building uses power it takes power from the grid. A 'bi-directional' (two way) meter will be installed that records how much power flows in either direction. If the building produces more power than it uses, then the power company pays money to the account holder (Shire of Strathbogie). At the very least these panels will reduce the amount of the power bill.

In our climate we can expect each kW of solar panels to produce, on average throughout the year, about 4kWhrs of electricity per day. So on average these two buildings will generate about 39kWhrs of electricity per day. To put this into perspective, in 2009 the average daily household electricity use was about 20kWhrs per day – which is actually quite wasteful. Energy conscious Australian households have their electricity consumption down to below 5kWhrs per day.

The grid interactive installation is efficient because it makes use of and supports the existing grid network instead of having to install an (energy and financially) expensive array of batteries, maintain these, and replace them every seven years or so.

David Arnold

Deflect Unwanted Heat

2010-05-26T04:10:00.000-07:00

Deflect Unwanted Heat
The biggest way that the building deflects unwanted heat is by the solid shade provided by the roof. We have greatly enhanced this deflection of heat by painting the roof with heat reflective paint, and by replacing the old skylights that were effectively a hole in the roof, with the roof windows that have solid canopies and appropriate eaves.
Heat Reflective Paint
Applying heat reflective paint was the single biggest and most cost effective impact we have had on the operation of this building. For approx $14 000 excl. GST, the 1600sq metres of roof over both buildings has been painted. The paint we used, Astec Energy Star white, is said to reflect 89% of heat, and is also very good at releasing heat to the night sky – 89% emissivity.

Kevin Jacka applying heat reflective paint to the roof of the Meeting Room. It is bright up there!

Afternoon on the roof of the Community Complex. The sun is behind the camera, so the light and heat is being reflected away. This roof is mostly flat or low angle, so the glare mainly only effects people walking on the roof, or passing helicopters. For a steeper roof a darker colour of heat reflective paint could be used, to produce less glare. Note also reflective tinting on high windows of Hall, visible to left of picture. It is 3pm on 23rd February, and the sun is just about to start shining onto (before tinting, into) these high windows.

After applying this paint we received many comments from the regular users of the building that it is now appreciably cooler in summer. The cost to supply and apply this paint worked out to about $9.50 /sq metre, including GST. It is expensive as a paint, but can be relatively cheap as a cooling strategy for difficult to insulate roofs.

Most of my direct experience with this paint is with this building, with its very poorly insulated ceiling. However Kevin Jacka, the painter, then went home and painted the metal roof of his own weatherboard house with this paint. His ceiling had about R2.5 insulation. On the summer's day that he put just the primer/undercoat on, his wife came home and said “The house is cooler.” Kevin put the top coat on, and is pleased with the effect. The paint may well be worthwhile applying on roofs where the ceiling is insulated.

However it is a plastic paint and I would like to know more about how it degrades in sunlight before using it on roofs that supply drinking water. I have asked the supplier for more information about this, which they have not as yet provided.

Heat reflective paint is also available for tile roofs, and for walls. Tony Nicholas has used it to very good effect on a west facing wall of his brick house in Hurt St Violet Town. [At Tony's initiative the EcoLiving Project is also encouraging VicTrack to put this paint on the metal shelters on railway platforms.... we'll see how we go with that. I am sure it would be very worthwhile, if they decide to do it.]

Replace skylights with roof windows
see also Use Energy from the Sun The old skylights leaked air, occasionally water until patched up, and definitely leaked heat and cold.

This old skylight above the kitchen needed to be replaced, and was a hole in the roof letting in heat, cold, and the sun's rays in summer.

Andrew Otto installing the supper room roof window at midday on December 21, summer solstice. Note the shadow line from the eave extends right to the front of the flashing, well away from allowing sun to enter the room below.

Install apropriate eaves on north windows
There were a number of north facing windows around these buildings that, while being valuable in winter, needed an eave to keep out summer sun.

New canopy/eave installed over north facing window in library courtyard. Shown in May 2010, with warm light entering the library.

Window tinting
Window tinting film can be applied to the inside of existing windows to deflect unwanted heat. This is a compromise solution, because with the deflection of heat comes reduced light passing into the building. A basic purpose of windows is to let in light. However some windows in these buildings, particularly in this case west and south west facing windows, were problematic for letting in summer sun, and we accepted the compromise of reduced light.

Paul Natalizio applying film to a west facing window in the Supper Room. Reduced light from these windows is now more than compensated for by light from the new roof windows. In summer the blinds were kept drawn anyway, because of the sun's heat, so the windows are now more functional than they were.

We used Optitune 15% film, which lets 15% of light in, and rejects 84% of heat. Paul of GV Window Tinting gives a lifetime guarantee on his application of this film for private homes, and a 10 year guarantee for commercial installations. Why the difference? Because the tinted windows must only be cleaned with mild cleaners, and he has found that cleaners of commercial buildings tend to use stronger cleaning products that reduce the life of the film. Sheryl Taylor, the VT Hall Committee, and Strathbogie Shire have all taken note of this. Sheryl only uses mild cleaners at the Hall, anyway.

Mike Larkin preparing wiring for the big fan in the Hall. Note reduced light coming in from the tinted SSW facing windows to right of picture, compared with the NNE facing windows at left. Before the windows at right were tinted, the sun would start shining right into the Hall in the late afternoon, heating it up just before a summer's evening event.

Heat Reflective Blind
Unlike permanently applied tint film, a heat reflective blind can be raised and lowered, giving control over when the effect. It can be raised to allow more indirect light into the room when the sun is not shining in, or to allow winter sunshine in to warm the room. It is more expensive than tinting, but preserves more of the use value of the window.

Sean, Indigo and Steven demonstrate the open-able heat reflective blind installed on a west facing window at Violet Town Community House. This does require someone to think about how the blind works, and actually open it when appropriate – in winter for example to allow the afternoon sun to shine in.

Landscaping for shade
Of course buildings, or badly sited windows, can be also be shaded with vegetation, which is a less energy expensive, and financially cheaper, strategy than high tech window tinting. This works well if well managed. Best if a gardener lives in the building, thinks about how it works, and manages that vegetation to best effect. For this public building we mostly had to accept that the landscape plantings will remain pretty much as they are.

Cutting back the tops of the existing photinia bushes to let winter sun into the Main Hall is one exception. See Use Energy from the Sun. Creating shade for the entry courtyard is another exception. If we can create a leafy shaded space over that courtyard we will deflect heat, create active cooling through transpiration of moisture through the leaves, and create a cool air space from which air can be drawn into the building.

Pergola frame over south facing courtyard garden is to carry four grape vines, which will be guided up the chains hanging from each corner. Shade from the vines will further cool this space. Pergola constructed by Comspread Engineering. Courtyard garden about to be re-landscaped by Graham Jones and Yuta.

Constructing this pergola to carry grape vines and shade this courtyard in summer is an excellent cooling / energy efficiency strategy, but the decision to construct the pergola out of steel is very questionable. I took advice that it should be constructed with galvanised steel for a longer life than timber. On reflection I would prefer to have used very dense Australian hardwood such as Sugar Gum, Ironbark or local Box eucalypt, which in my own and others experience is very durable for outdoor construction.

For any sustainable / energy efficiency project, the embodied energy in the material needs to be taken into account. For the steel, think about the energy cost of digging up the iron ore in Western Australia, digging up the coal in NSW or Queensland, freighting both to port, shipping them to China, freighting these to the steel mill, burning lots of coal to make the steel, then freighting / shipping / freighting the steel back to Violet Town! Compare this with the small energy cost of cutting up a log from within 100 kms, possibly much less, to get durable hardwood timber.

David Arnold

Insulate

2010-03-04T22:51:00.000-08:00

Stramit Strawboard ceiling/ Cliplock roof system
A basic first step for these buildings in our climate is to improve insulation where possible.
Most of the roof/ceiling system for Community Complex building is poorly insulated. The existing roofing / ceiling system would have a combined R value of about R 0.6 or less. With only 50mm air space between the top of the ceiling panels and the roof decking, there is no room to add much insulation. The cost of raising the whole roof about 200mm to accommodate insulation was investigated, and found to be too expensive.

So what was the best we could do with the existing roof and ceiling, given the way the building is used?

Trevor working on the roof over the Supper Room. Only 50mm air space between the top of the strawboard ceiling panel and the bottom of the metal decking. Cork had been laid to insulate the steel beam from the decking, but this either never worked or had stopped working.

The 50mm compressed strawboard ceiling panels, although only rated as R 0.62, are not too bad for a building that is usually only occupied [and heated / cooled] for short periods. However the steel I beam that carries these strawboard panels transmits heat and cold from the roof decking into the ceiling below. On a hot day the exposed internal edge of the steel I beams in the ceilings would become too hot to touch – probably about 60 degrees, and radiate heat into the room.

Most of the heat part of this problem was solved with heat reflective paint. This was one of the single biggest and most cost effective impacts we have had on the operation of this building. For more details see Deflect Unwanted Heat on this blog.

Timber Cover Strips
However the heat reflective paint does not help to keep heat in the building in winter. The building is often empty and unheated, is only used for occasional events, and so is only heated for short periods, usually 4 hrs or less. The strawboard ceilings give quite acceptable insulation for short period use. It probably takes more than four hours for much heat to begin passing through the panels. The metal beams can still radiate cold from outside to in, though. While not a perfect solution, our compromise was to cover the exposed internal edge of the metal beams with timber boards.

Yuta and Trevor fixing timber cover strips to the exposed internal edge of the steel roof purlins in the Supper Room. These timber strips have also been applied in the Kitchen, Community House, Main Hall, and Foyer.

Insulation above ceiling tiles
The Meeting Rooms area has a different ceiling system, of suspended acoustic ceiling tiles. There was no insulation over these, and only about a 40mm thick roofing blanket jammed between the decking/sarking, and the roofing purlins.

It seemed that the obvious thing to do was to add bulk insulation above the existing ceiling tiles. However replacements for the existing ceiling tiles are no longer available, and it was going to be impossible to work on these tiles without damaging some of them. Plus working on the old ceiling tiles required care and patience, which comes easily to some tradespeople and builders, but not all.

Companies offered to replace all of these ceilings, which would have been wasteful. We don't just want to Reduce, Re-use and Recycle. We need to Refuse, Reduce, Re-use, Repair, Recycle, Re-invent... and so on. (Reconnect, Relocalise...)

So we dismantled and replaced the existing ceiling from the main Meeting Room, only, and salvaged the good tiles from this area to replace tiles in the meeting rooms foyer, VTAG, and RSL rooms.

Meeting room with old ceiling tiles removed, showing only thin roofing blanket insulation under the decking. Rob and Luke from Total Plaster Supplies are about to install new ceiling tiles, and place insulation above these. Ceiling height is immediately above the window and air conditioner.

Aldo Borg helped to dismantle the old ceiling tile framing, as he had a use for it in insulating his shed. This was a big bonus for our efforts to avoid waste.

Mike (obscured) and Paul Larkin putting the old light fittings into the new Meeting Room ceiling. The bulk insulation above the tiles can be seen at the top of the picture.

Gaspard (obscured) and Yuta placing bulk insulation above the old ceiling tiles in the meeting rooms foyer, and replacing damaged tiles as they go.

Careful repair and re-use of the old ceiling tiles was much cheaper than replacing the whole ceiling. This contributed to the project having enough money to put a new and insulated tile ceiling in the Library.

Denise at work in the Library, under the newly installed and insulated ceiling tiles.

Double glazing
While the new roof windows were fitted with pre-sealed double glazing, we did not consider it cost effective to retrofit double glazing to existing windows. There were so many other thermal leaks around the building, including active draughts, that were cheaper and more cost effective to address. Also even where rooms do have air conditioning fitted, these are only operated for relatively short periods. A lot of the time the building temperature is not so much different from the outside temperature, so the total heat transfer through the windows is moderate.

David Arnold