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Lecture 2:

Listen to part of a lecture in an environmental science class.

Ok. So environmentalists have created green building programs in order to encourage green building construction, which means environmentally friendly buildings that produce a minimum of pollution. And our energy efficient. We’ve talked about like technologies that use solar energy for heating homes. Yes, that’s certainly something these programs to advocate. but they’re also concerned with construction because green building standards include the conservation of natural resources like trees. wood homes, such as those traditionally built here in the united states, require over an acre of trees over an acre of forest land in lumber, plus three to seven tons of waste are created on average during the construction process. so what if we could use a product that’s typically considered waste to build homes?

It’s being done. One of the materials used in green building construction is straw bales. yes, I’m talking straw, those short stocks that are left over in farm fields after grain crops are harvested. it’s it’s hard to get rid of as a waste product, and it’s usually burned. So instead of adding to air pollution problems by burning the straw, it’s compressed into bales and used to build homes. wow, i’ve never heard of using straw to build homes. well, straw bale construction isn’t a new technique. A pioneers on the American prairie, where there were no trees, constructed their homes of straw bales over a hundred years ago. then in many of those early buildings, made in what’s called the nebraska style are still standing. actually, straw bale construction has been used around the world for thousands of years.

And because of the very properties that make it a nuisance waste that it’s tough and hard to compost. That’s what makes draw a great building material. it’s the insulating properties of straw bales that are probably the strongest selling point. in fact, a standard straw bale wall provides about three times the insulation value of an insulated wall in a traditional wood frame house, which can drastically reduce the amount of heating or cooling needed to keep the house comfortable. so environmentalists love this construction method that basically turns a waste product into a building material, saving energy and saving trees. a paul.

So how do you make a house out of straw? It almost sounds too good to be true.

Straw bale houses are actually built out of standard rectangular agricultural bales.

they’re stacked like bricks to form the exterior walls. Then the straw walls are sealed with stucco. a stucco is a good, tough finish. That’s like cement or plaster.

these stuck owed straw bale walls can then be used as the structure to support the roof. the stucco skin acts as a thin shell over the bales and makes the buildings very stable.

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