More Information on
Passive Solar Design

A Solar home is thermally comfortable

year round and uses a minimum if any

auxiliary energy for backup heating and

cooling or domestic water heating

            It is healthy and non-toxic. Materials

are natural simple and do not emit toxic gasses,

 formaldehyde, dusts, funguses, or mites.

Definition: The use of the sun’s energy for heating and cooling living spaces. This is done by allowing the building to use materials that have natural energy characteristics when exposed to the sun.

 Passive Solar Principles

• Tight: They do not allow drafts through gaps in framing, or around widows, doors, and venting or electrical fixtures
• Well Insulated: Insulation is complete; all voids are filled to recommended amounts
• Orient to South: The long side faces the south for maximum amount of sunlight in winter, and minimum amount of sunlight in the summer.
• Collect Solar Heat: Due to South facing windows 5-8% of total floor area is in sunlight during the winter, and shade during the summer.
• Store Heat: thermal mass is critical for the comfort of a home, it stores and re-radiates heat at night.
• Distribution: Let heat transfer through the house naturally without high tech devises
• Controlled Ventilation: A tight well insulated house needs to breath. 

 Willow Bend uses these passive solar principles to heat the building without auxiliary heat. However, we do have a wood burning stove in case the need arises. In the past we have only needed to use the stove six times per each winter

Why Build a Straw Bale Home?

Straw bale homes can cut your utility bills by a considerable amount, since they are three to four times more energy efficient than conventional construction. Straw is also considered as a waste product that must be disposed of. When using straw instead of wood you are saving energy and using a renewable resource in place of other less renewable materials. Often these less renewable materials can be toxic and require more energy to produce and transport.  However, the most important reason for building a straw bale home is for the beauty it provides.

Most asked questions when building with straw bales

1.)   Will it rot? – Mineral content of straw is similar to wood (High in Silica), therefore, as long as you protect it from moisture, as you would with a wood frame house, it will last al long as a wood frame house.

2.)   Will it Burn? – A two hour fire test was performed on a straw bale wall by an independent testing company and even though it was exposed to two hours of near 2000* F, the rise in temperature on the opposite side of the wall was negligible, the straw inside the wall only charred where the stucco had cracked (because it had not cured when they started the test).

3.)   What about Bugs? – As long as the wall is sealed up in stucco, you will not have a best problem. Straw is not desirable to any termites in the Western U.S.

The Cost of a Straw Bale Home

The cost depends on a lot of factors. Do you want granite counter topes on custom cabinets or do you want to find some used cabinets at a used building supply outlet? Are you going to put in some “sweat equity” such as putting up the bales yourself, stucco, paint, ect? Do you want to spend $150 on that window or $1500? What kind of heating system are you going to have? Forced air or passive solar? Only after answering these questions, plus many more, can we tell you exactly how much it will cost for your home. Perhaps the simplest answer would be to compare building costs to conventional construction. The average home being built in Flagstaff today runs between $90 and $100 per square foot. A modest straw bale home will be in the same range.

Three Factors to consider when designing a home

1.)    Quality of Material

2.)    Quantity of Material

3.)    Budget (usually your budget is set and the quality and quantity have to be traded off to fit the budget)

The size of your home is also a very important consideration in both cost and sustainability. If you truly want to build an environmentally responsible home, consider cutting down the square footage as much as you can. The typical American home is increasing at an alarming rate. Sweat equity is a way to save money. If you are providing the labor, you can save many thousands of dollars. Most Straw Bales built so far have incorporated an old-fashion barn raising idea where a lot of interested people get together and help a friend or neighbor put up their house. One real affordability issue is the fact that if you incorporate passive solar design your heating bill could be virtually non-existent. Remember that the R-value (insulation rating) of the walls is about R-33 depending on the bale thickness. A 2” X 6” frame wall with R-19 insulation is actually about R-12 depending on how well it is built. Taking energy savings into consideration, your monthly expenses are lower with a straw bale and you have to understand that the price on energy is only going up! It would be better to put your money into the best insulation you can get up front.

Durability

Homes were first built of straw bales at the turn of the century in Nebraska. This was shortly after the time that mechanical balers were developed. Some of those homes are still standing and are in great shape today. Straw has been used in construction for thousands of years and homes that have used it for insulation or as a binder for clay walls show no rotting of the straw where the wall was maintained and kept dry.

Other Reasons to build with Straw

      Straw is usually burned as a waste product that puts more than twice as many pollutants in the air each year in California than all of the fossil fuel power plants

Fun Facts about Straw Bale Homes

The oldest straw building recorded was a school house in Bayford, Nebraska built in 1886 or 1887.

In 1903 straw buildings in Nebraska were built from native rangeland grasses and plastered with mud.

Rice straw is high in silica and decays very slowly. The high silica content of rice straw gives it extra strength and longevity.

Since Straw Matures in a matter of months millions of tons of these environmentally sound building materials are produced annually. Compared to the decades it takes for trees to grow large enough for the sawmill.

Straw bales are highly fire-resistant because, with stucco on each side of the wall there is too little oxygen left to support combustion.

 In 1936 Dr. William Burrit constructed a two story mansion in Huntsville, Alabama. He used straw fill for insulation.

In the early 1900’s and 1950’s straw bale was a very popular building method. However, in the 1950’s when mass-produced construction materials began to emerge, it lost its popularity.

Straw Bale construction was reintroduced in 1974 by Roger Welsh who wrote an essay titled “Baled Hay”

 In October 1993 the first permit for a load bearing straw bale home was granted in Tucson, Arizona under section 105 and 107 of the U.B.C.

 These interesting facts can be found at

http://www.geocities.com.Athens/Acropolis/8308/history.html

Solar Living Sourcebook by John Schaffer