Comments on: Does Eco Building Decrease Energy Consumption?

By: Sampie

Sampie — Mon, 21 Sep 2009 19:38:15 +0000

I am convinced that the reflection of so many Zink(like) roof tops world wide, can cause a dramatic increase in heat generated, as the sun rays are concentrated and reflected back to the sun.
If we would consider painting all roof tops white, we may add lots of light but a dramatic reduction in heat. Try it …

By: Gary W. Reilly

Gary W. Reilly — Mon, 01 Dec 2008 08:33:23 +0000

Dear Lizanne and All,

I manufacture roof tiles out of recycled plastic and sand.

I am working with Eco-build (sandbag homes) and Imison (EPS – Expanded Polystyrene Homes) for contracts in 5 countries, excluding South Africa.

They are 2 builsing methodologies that are working right now. I personally agree that the straw homes are the best insulators of the lot, but the community involvement in sand-bag homes is truly wonderful and the speed at which both sets of homes can be erected, allows us to take on contracts for 1M homes in 5 years without even flinching. Hope this helps…

By: Clarissa Hughes

Clarissa Hughes — Wed, 23 Jul 2008 11:47:18 +0000

Yes, you’re right Terry. The energy that goes into being energy efficient is often not worth it. That’s why I like the claybrick houses idea. The bricks are sun-dried and made in old ice-cream tub moulds. The sense of creativity that it gives to otherwise unemployed people is something to behold. A good thing all round, provided the source of the clay is nearby.

By: Terry McClement

Terry McClement — Thu, 17 Jul 2008 12:53:58 +0000

In answer to the question: “Does eco building decrease energy consumtion”. The short answer is NO. The long answer is do your homework – no matter what you do, you consume energy and if you already have a home, are you going to break it down when you have built your eco house, or will some body else move in and continue burning up energy? Will you ever recover, in your lifetime, the energy you put into building your eco house? Can you show me a factory producing solar voltaic panels that derives it’s own energy from solar voltaic panels? So straw bales consume carbon dioxide, but how much diesel fumes were produced plowing the land, havesting, baling and transporting them? You need to take a global holistic view.

By: Terry McClement

Terry McClement — Thu, 17 Jul 2008 12:41:41 +0000

Get the book “Building with awareness” – the construction of a hybrid home DVD & guidebook by Ted Owens. It will answer all your questions.

By: Clarissa Hughes

Clarissa Hughes — Thu, 12 Jun 2008 08:47:49 +0000

You can often find good advice from locals. Their methods have been tried and tested over many centuries, if not millenia. I think specifically of the claybrick houses that still stand along the West Coast of South Africa, not too far from Ceres. The method is enjoying a revival, and you will find examples by visiting the Duinepos chalets in the West Coast National Park. So if you have any clay on or near your farm it might be worth investigating.

By: Ralph Pina

Ralph Pina — Tue, 10 Jun 2008 17:18:28 +0000

Regarding heating and cooling a building, it seems the most important things one can do are:

1. orient the building so that living areas face north for winter sun into the house (combine with thermal mass so that a mass inside the building is warmed by the sun and holds the heat through the night)

2. have overhangs or deciduous trees/vines on the north side so that living areas are in shade in summer

What you are referring to in comparing the ecological construction methods with mainstream methods is that the former contain less “embodied energy”

More nifty techniques that they’re using at the Sustainability Institute:

1. a rock bed below the floor: in summer they let cool air into the rock bed at night and during the day let it flow out of vents in the floor; in winter they pump warm air from the ceiling cavity into the bed and release the stored warm air through the vents during the day

2. Apparently 1-2 m down in the ground the temperature anywhere on earth is a constant 21C. So you run pipes containing water (?) through this layer and then up into your floors. So it tends to keep the floors at a constant temperature. I think they call it a geothermal heat pump.

By: Lizanne Malherbe

Lizanne Malherbe — Mon, 02 Jun 2008 17:46:09 +0000

Yes that seems like a valid point to consider. What I’ve seen here in South Africa at a cob house, was that they used old windscreens (collected from a scrap yard) as windows. This seems like a very very clever way to reuse second hand materials, PLUS get your windows virtually for free. Ventilation is then controlled with holes in the walls at specifically placed high and low spots.

By: AJK

AJK — Fri, 30 May 2008 13:44:56 +0000

Actually South Africa is a bit behind Europe as far as I know. In Europe they use double glazing to keep houses more energy efficient, while in South Africa we don’t. It might be because we don’t have such extreme weather (going far below 0 degrees Celcius ).

By: Gustavo

Gustavo — Fri, 30 May 2008 13:19:31 +0000

what about special glassing to lessen or increase the effect of the sun, would that have some effect during daytime? I’m just curious.