Principles of passive building design.

Searching the internet you sometimes come across little gems which one suspects are not actually meant to be in a public directory of the website.

Recently I came across an excellent article about passive design principles for housing. The article is in draft form so I am hesitant to publish the URL.

I will tell you that article is in MS word format and the the first line is "Passive design for ClimateSmart Housing" so you can search for it yourself.

The article's focus is on housing in the state of Queensland Australia, a massive state which forms the north-east corner of the Australian continent and has a total area of 1.8 million square kilometres (or 700,000 square miles).

Queensland is 2 and ½ times the size of Texas in the USA and is 4 and ½ times the size of Japan so the state covers a range of climate zones.

Where The Woman and I will live, the climate zone is Sub-Tropical, coastal.

Irrespective of where you live or build, these six principles are valid, although they way the are applied will of course differ depending on the climate in your area.

We know that to build a house that is comfortable to be in and energy efficient, we need to incorporate six passive design principles which, according to the article, in order of priority are:

1. "orientation – generally, wherever possible, orientate the living area to the north for winter warmth in the cooler parts of Queensland and away from the summer sun in north Queensland. Utility areas such as the garage, storage rooms, entry and laundry should be positioned to the south-west to shield the house from the setting sun.*

2. ventilation – openings throughout the house allow summer breezes to provide cooling cross-ventilation.

3. shading – effectively shading walls and windows prevents heat transfer e.g. roof and window eaves.

4. insulation – insulate the roof space against heat and cold transfer, and insulate the walls where no overhangs are provided.

5. thermal mass – build in thermal mass to absorb heat where it can be useful to re-radiate this heat at night (NB. this principle applies mostly to Zones 3 – Hot Arid, and 5 – Warm Temperate where hot days can be followed by cool nights).

6. materials – use energy-efficient materials appropriate for the climate zone to improve thermal performance e.g. external walls, windows/glass/tinting and solar pergolas. "



Note: To point 6 I would have to add colour. Light coloured finishes to walls and roofs can reflect a lot of heat.
The space between your ceiling and roof can get very hot so do what you can to reduce that heat. Insulate of course but avoid dark colours on walls and roofing.

Solar reflective paint is now being advertised with claims that it reflects the sun's rays.

In Australia the versatile steel products such as Colorbond steel is increasingly popular as a roofing material, so much so that it is trendy and is now therefore manufactured in a wide range of trendy colours, light dark and in-between.

Putting a black steel roof on a house in a sub-tropical location would seem very silly.
But I could show you where it has been done. Difficult to believe that the builder and the roofer would not advise strongly against this.
But then the customer is always right, right?

*Orientation given is for the southern hemisphere. North of the equator you would- orientate the living area to the south.

For more information on sustainable homes go here.

Gutter talk

We have some large trees in our yard, as do many of our neighbours. Its nice to have such magnificent specimens and to watch the truly wonderful native parrots which frquent them throughout the year.

But trees shed leaves, so this week I have spent some time sitting on my roof cleaning leaf litter from the guttering. Its a tedious job and not without its dangers. In the area where we live, having gutters full of leaf litter is not recommended for two reasons.

Firstly, during heavy rain the water cant get off the roof quickly enough so banks up in the roof valleys which feed the gutters and ends up entering the house and running down walls, windows and doors. Secondly, gutters blocked by dry leaf litter can cost you your home during a bushfire.
We are prone to bushfires in dry years and embers carried on the wind can land in your gutters and set fire to the leaf litter, fire which can quickly spread into your roof.

The conventional wisdom is that you clear leaf litter from your gutter before the bushfire season starts. Not only does this prevent fire from taking hold there, but it means that you can use rags to block the holes at the top of the the drain pipes and flood the gutters with water as an added precaution against bushfire.

For anyone who collects the rainwater from their roof it is important to keep leaf litter and everything else which is animal or minerals out of your water tank.

So what can you do to stop leaf litter clogging up gutters in the first place?
You might want to consider some form of gutter guard like:

http://www.gutterguardian.com.au/
http://www.gumleafgutterguard.com/
http://www.aussiegutterprotection.com.au/
http://www.theleafman.com.au/

Arguably a better approach is to install guttering which is designed so that any leaves or debris which lands on it will be blown away by the next light breeze.
Formerly called Enviroflow its now called Smartflow Check it out:

http://www.enviro-friendly.com/smartflo-guttering.shtml

Blowin in the Wind

Renewable energy has a giant part to play in the push to reduce carbon emissions and wind power is one renewable which is having a renaissance, even finding a place in the back yard.
Although eventually losing favour to steam, electrical and oil fuelled engines, wind power was used in antquity, noticeably by the Persians and the Chinese. A wonderful history of wind power is here.




Around 1400 the Dutch started made a more efficient windmill and never really gave up on them.
One of the many interesting sights in Holland today is that of traditional molens (mills) alongside modern wind turbines.
Wind is now used to generate electricity on a massive scale. In Scotland construction of Europe's largest onshore wind farm, Whitelee is almost complete. Its 140 turbines will have the capacity to produce 322MW of clean green energy, enough to power over 180,000 homes.



Whitelee wind farm will produce more than two percent of the country's annual electricity needs. An even larger project, the Clyde Wind Farm has been approved and its 152 turbines will be able to power 320,000 homes.
Offshore wind farms are seen as having the potential to generate around twice as much electricity as those onshore.

Several years of drought in Australia prompted the New South Wales State Government to commission a Water desalination plant at Kurnell near Sydney.
The state government is also getting involved in Capital Wind Farm being built at Bungendore, near Queanbeyan in southern NSW. to offset the massive amount of electricity needed to run the desalination plant.

So wind works, but what about in your back yard? In over seventy different countries you can buy a Skystream 3.7™.



According to Solarshop.com the Skystream 3.7™. is "A new generation grid connect wind turbine that hooks up to your home to help you reduce or eliminate your monthly electricity costs. It’s the first compact, user-friendly, all-inclusive, purpose built domestic grid connect wind generator.



If your site fits the following criteria, Skystream will work for you:
1) At least 16km/h average wind speed (best results at 20km/h or more)
2) Your property is at least 2,000m² and has unobstructed views.
3) The local zoning allows a structure that is at least 12.8m tall
4) Your local utility has an existing interconnection agreement for homeowners
Depending on your installed cost, cost of electricity, and average wind speed, Skystream can pay for itself in as little as five years"



Sadly, although she would like one, there will be no windmill for The Woman and I. We just do not get enough wind to make it an economic proposition.

But for some, it will be just what they need.

As good as it gets. - housing design.

Shelter is a basic human need.

Apart from those unfortunate enough to be homeless, in jail or otherwise institutionalised, the rest of us live in some form of domestic housing.

Whether renting or buying, for most people, paying for the roof over our head is a major expense.

Whatever the type, style or shape of your abode, your ability to choose your housing, will most likely have been dictated by the price and availability of accommodation in your area.


Often, you cannot afford to be fussy. Perhaps you need to move in a hurry or sign a lease quickly before someone else beats you to it. You just have to take what you can get.


Others are more fortunate in the choice department. They are able to buy or build a new brand house.

Why then do so many of them buy or build housing which is badly designed, wastes energy and is unsuited to their needs?


Its human nature to want to improve your lot in life so over the centuries as the general public became relatively wealthier, people have wanted to live in bigger and more luxurious houses.

The reasoning seems to be that what was good enough for your grandparents was not good enough for your parents.

And what was good enough for your parents is not good enough for you.

In the best traditions of capitalism, the building industry, developers and real estate agents, have been only too happy to construct and sell inferior designs disguised as quality housing.

Very few gave any though to the eveyday practicality and long term sustainability of the product..

The motto was and still is "Make it bigger and make it cheaper and they will buy it"

It seems that wholesale change will only only come through government legislation forcing builders to adopt more environmentally sound building practices.

The sad thing is that good sustainable design does not have to be expensive.

And allowance for more expensive passive solar features such as grid-feed PV systems can be incorporated at the design stage and added later.

To see just how good sustainable housing design can be look at The Ecovillage at Currumbin which was awarded the World's Best Environmental Development in the 2008 FIABCI Prix D'Excellence Awards in Amsterdam.




.

Sewage, Sewerage and Biolytix

It impossible to understate the beneficial effects that clean drinking water and efficient sewerage. has on the health of mankind.

(Sewage and Sewerage are terms which are often used incorrectly. So just for the record, Sewerage is the harware, the pipes and tanks. Sewage is the runny stuff which goes through them).


The disposal of human waste is not generally a topic for polite conversation but if your house is not connected to a municipal sewerage system then you have to talk dirty.
Options such as composting toilets may appeal to true environmental warriors but I think most of us who grew up with the flush would prefer to stick with it.
Septic systems are common and for many, septic tanks were certainly a big improvement on the pan which the poo-cart man used to come and empty.

Septic tanks work by collecting all the waste water from a home: Sewage from the toilet, bath water, kitchen sink water, the lot. Solids sink to the bottom to decompose, fats float to the top and the grey water in between is discharged into the soil surrounding the tank. When problems arise things can get very messy.

Luckily for us there are systems on the market today which are a quantum leap ahead of the old septic tank. One such system is the award winning Biolytix. which mimics nature. Biolytix uses insects and organisms to turn grey and black water into irrigation water.

The Woman and I have already chosen Biolytix as our preferred waste disposal system.

What follows is an except from an article Turning waste to water By: FOES-LAMB,, Philippa, which appeared in The Nelson Mail, Feb 15, 2008.

``Biolytix is a very reliable and effective home sewage treatment system. It has been used in Australia for 30 years and has been installed in the Tasman area for the past two years, mainly in unsewered rural areas.

``The system uses tiger and red worms to break down human and Insinkerator waste, effectively providing pretty clean water that can then be used on most of the garden. We use a mix of these worms because red worms prefer slightly lower temperatures while tiger worms work well at higher temperatures - it's a good balance.''

As well as worms, beetles and microorganisms take up residence in the tank and also help to break down the waste material.

A major drawcard of the system is the fact that there is no odour when a tank that is in operation is opened, Robert says. ``There really is no odour, which is pretty amazing. A common human perception is that `what goes down must smell'. This is one of the great things about the Biolytix system - it is a complete, individual ecosystem.

``Each tank has several layers of net bags that are half-filled with short lengths of black drainage pipe, which provide a dry platform for the worms and other organisms.''

Worms are introduced to the tank after two people have been living in the house for about a month.

``One kilogram of worms is introduced after this period of time - the reason for the delay is so there is something for the worms to begin working on straight away.

``If a family of five moves into the house, the worms could be introduced earlier, at around two weeks.''

All the household waste water - which is termed grey and black - goes into the tank, along with waste from the kitchen sink waste disposal, if one is fitted. You don't have to have a waste disposal, but worms love kitchen scraps, so it seems logical to make the most of this. These days, many of us have busy lives and there's not always time to make home compost.

``The turnaround time is very quick. The liquid content is filtered down by gravity and is available for pumping when there is approximately 200 litres collected,'' Robert says.

``The liquid that collects at the bottom of the tank is then pumped into a pressure-compensated drip irrigation system which runs around the plantings surrounding the house.

``Based on a three-bedroom home, there are 540 linear metres of dripper irrigation which is covered in bark or other mulch.

``The pump operates at pressure, and the diaphragms in the drip irrigation pipes won't open until the pressure is right. They all open at 11psi, ensuring there is even distribution on all the line.

``The pump can also be fitted with a distribution indexing valve, which allows it to pump waste water to one side of the garden one day and the other the next, and this can be split into as many fields as you would like. This helps ensure each area of the garden receives a thorough watering, which is more beneficial for the plants.

``This waste water can be used on grapes, fruit trees, citrus and roses - in fact, anything that grows above ground. It is not advised that it be used where root crops such as potatoes or carrots are being grown."

Here is another explanation of How Biolytix Works.


I don't work for Biolytix and I dont expect to pay anything less than full price for my system, but this product has won many awards and deserves free pubilicity.