Green Home Building

Green Home Building: Article about Principles of Sustainable Architecture

Thirteen Principles of Sustainable Architecture

by Kelly Hart

As “consumers” we are frequently confronted with life style decisions that can impact our environment. There are a few choices in this life that can make a big difference in what the quality of life will be for those who follow us. Going with the flow of our culture is hard to avoid, and unfortunately the flow is not in the right direction for evolving a sustainable future.

One of the most momentous choices that any of us will make is the kind of house we live in. I have come up with a list of thirteen principles of sustainable architecture that can guide you in your housing choices.

Small is beautiful. The trend lately has been toward huge mansion-style houses. While these might fit the egos of those who purchase them, they don't fit with a sustainable life style. Large houses generally use a tremendous amount of energy to heat and cool. This energy usually comes from the combustion of fossil fuels, depleting these resources and emitting greenhouse gases and pollutants into the air. Also, the larger the house, the more materials go into its construction; materials which may have their own environmental consequences. A home should be just the right size for its occupants and their activities. My wife and I (and our two dogs) have happily lived in a forty foot bus for the last four years. The key to this is efficient use of space, good organization, and keeping possessions to a manageable level. We do look forward to spreading out some in the passive solar, earthbag home we are building.

Heat with the sun. Nothing can be more comfortable for body and mind than living in a good solar-heated house. I say “good”, because proper design is crucial to the comfort of such a house. You may have gone into a solar house and felt stifled by the glaring heat, or perhaps you shivered from the lack of it. Good passive solar design will provide just enough sunlight into the rooms to be absorbed by the surrounding thermal mass (usually masonry materials), so that the heat will be given back into the room when the sun goes down. The thermal mass is a kind of “heat battery” that stores the warmth, absorbing it to keep the room from getting too hot during the day. Equally important to thermal mass is insulation (such as straw bales or crushed volcanic rock) that will keep that heat inside. Thermal mass materials need to be insulated from the outside, or else they will just bleed that warmth right back out. A rock house might have tons of mass, but be uncomfortably cold because of this energy bleed. So a good solar design will utilize materials of the right type in the right places, blending thermal dynamics with utilitarian design. There is much more to be said about solar design, and there are many good books on the topic.

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Keep your cool. As I suggested above, a well designed solar house is both warm when you want it, and cool when you want it; that is to say, the temperature tends to stay fairly even. A good way to keep your cool is to dig into the earth. If you dig about six feet into the earth, you will find that the temperature there varies by only a few degrees year round. While this temperature (about 50-55 degrees F.) might be too cool for general living comfort, you can use the stability of the earth's temperature to moderate the thermal fluctuations of the house. If you dig into a south-facing hillside to build, or berm the north part of the house with soil, you can take advantage of this. The part of the house that is under ground needs to be well insulated, or the earth will continually suck warmth out of the house.

Let nature cool your food. In the old days people relied on pantries and root cellars to help keep produce and other provisions fresh. Ice boxes made way for refrigerators, which are obviously much more convenient, but somehow the use of cool pantries and root cellars also fell by the wayside. This is too bad because these spaces have functions that a refrigerator simply can't replace. Root cellars can store large quantities of produce from the time of harvest until the next summer. Cool pantries can store some produce, but also all manner of other foodstuffs and kitchen supplies can be kept there. Cool, dry storage is the best way to preserve most food. The cool of the earth can keep a totally bermed pantry or root cellar cool; the night air can also be used to cool a storage room. The convenience and security of having ample provisions at your finger tips can not be beat.

Be energy efficient. There are many ways to conserve the use of fossil fuel. Using the sun, wind, or water to produce electricity is one. If you choose to do this, you will be forced to be careful in the way you use your electricity because it is limited. Whether you get your electricity from alternative sources or from the grid, it pays to choose energy efficient appliances. Front-loading clothes washers, for instance, use much less electricity, water and soap than the top-loaders. Compact florescent lights use about a third of the electricity of standard bulbs. Many appliances use electricity by just being plugged in (known as phantom load); be sure to avoid this.

Conserve water. The average person in the U. S. uses between 100 and 250 gallons of water a day. I know it is possible to get by just fine on one tenth that amount. The use of low water capacity toilets, flow restrictors at shower heads and faucet aerators are fairly common now. More radical conservation approaches include diverting gray water from bathing, clothes washing and bathroom sinks to watering plants; catching rain water from roofs and paved areas for domestic use and switching to composting toilets. These can be very effective and safe means of water conservation if done carefully to avoid bacterial infestation. Landscaping with drought tolerant, indigenous plants can save an enormous amount of water.



Use local materials. There are several benefits to using local, indigenous materials. For one, they naturally fit into the “feeling” of the place. For another, they don't burn as much fossil fuel to transport them, and they are likely to be less processed by industry. An example of building materials found in our corner of Colorado would be rocks, sand, adobe and scoria (crushed volcanic rock).

Use natural materials. Again, naturally occurring materials often “feel” better to live with. When you step onto an adobe floor, for instance, you feel the resilient mother earth beneath your feet. A major reason for choosing natural materials over industrial ones is that the pollution often associated with their manufacture is minimized. For every ton of portland cement that is manufactured, an equal amount of carbon dioxide is released into the air. And then there is the matter of your health; natural materials are much less likely to adversely affect your health.

Save the forests. Having lived for many years in the Pacific Northwest, I can attest to the appalling degradation of national and private forests. While wood is ostensibly a renewable resource, we have gone way beyond sustainable harvesting and have ruined enormous ecosystems. Use wood as decoration. Cull dead trees for structural supports. Use masonry, straw bales, papercrete, cob, adobe, rocks, bags of volcanic rock, etc., instead of wood. Unfortunately it is difficult to get away from lumber in making a roof, so consider making a dome from materials that can be stacked. Domes are also more energy efficient and use less materials for the same space as a box. A conventional straw bale house only diminishes the amount of wood used by about 15%!

Recycle materials. If the materials already exist, you might as well use them, because by doing so you are not promoting the creation of more of them. You might also be keeping them out of the landfill, or keeping them from being transported for further processing. Wood that is kept dry does not degrade much, nor does glass. All kinds of things can be used in a house. We're using old metal wagon wheels to support the window openings in our earthbag home.

Build to last. There is an attitude in this throw-away society that an old house might as well be replaced by a new one. Unfortunately this is often true, because of shoddy construction or poor choice of materials, or lack of maintenance. A well made house can last for centuries, and it should. Moisture getting into a building can lead to ruin, and it is hard to avoid this, whether from the outside environment or from condensation from within. For this reason I am partial to the use of materials that are not degraded by moisture.

Grow your food. Why not ask your house to help nourish you? With all of that south-facing glass, you might as well devote some of it to a greenhouse. Herbs and salad greens can be grown year round. What a pleasure!



Share Facilities. A basic tenet of sustainability is to share what you have with others. Doing this can diminish the need for unnecessary duplication of facilities. In this way a group of people can not only have fewer tools or appliances or functional areas, but at the same time they can have available a greater variety of these facilities. This benefits both the environment (through less industrial activity) and the individual (by providing more options for living.)


Green Home Building: Article about Messages from Mesa Verde

Messages from Mesa Verde

by Kelly Hart

I visited Mesa Verde in Colorado near the Four Corners. This was my first encounter with the “ruins” of the ancestral Puebloan people, progenitors of the Pueblo and Hopi nations. I had heard about Mesa Verde since I was a kid, but nothing could prepare me for the awesome reality. Despite the influx of tourists, there is a peaceful and spiritual quality that persists.

The most famous aspect of what was left behind there are the cliff dwellings, which are certainly magnificent. These finely crafted rock structures emerge from huge alcoves within the cliff faces, and from a distance resemble swallows' nests, fitting into the surrounding rock just as naturally. Actually the cliff houses represent the culmination of about seven centuries of habitation at Mesa Verde. Then around 1300 AD the people abruptly abandoned their homes and moved south and southeast to establish other communities. There is much speculation about why they moved, but the most likely cause was a prolonged period of at least 12 years of drought.

The cliffs were only occupied for the last two centuries at Mesa Verde; before that, all

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habitation was on the mesa above. At first the people made rectangular pit houses that were dug partially into the ground and then built up with poles and sticks plastered with mud. The entrance was via a hole in the roof with a ladder descending to the floor below. Archeologists believe that from this simple pit house both the freestanding masonry pueblo and the underground circular kiva evolved. The cliff dwellings combined both interconnected pueblo “apartments” and kivas, which were used for ceremonial and community functions. Some of the larger cliff dwellings may have housed over a hundred people. Most of the Mesa Verdeans lived in this communal way, but there were also many smaller housing units scattered throughout the area. It is obvious that they were a very cooperative society.

Little did they know that their style of architecture would become so enormously popular many centuries later. “Pueblo” or “Santa Fe” style building can be linked directly to them. The Spanish introduced modular adobe blocks that make the construction go faster, but the simple stacked rectangular shapes with protruding vigas is native American.

These people were primarily farmers, growing squash, corn and beans in terraced garden plots on the mesa tops. They carefully guided water to their gardens. The mesa itself slopes gently toward the south, which improves the solar gain for gardening, and the colder air slides down the canyons and off the mesa, which increases the growing season.

There is a lot of speculation about why they decided to start building communities within



the cliff faces. Some think it was for defensive purposes, although there is little evidence of violence to support this. My sense is that they moved to the cliffs for comfort. Some enterprising individual or family probably tried building a stone house on one of the many cliff ledges that faces south and soon realized that there were many advantages, which were pointed out to the others. Sealing off a cave or cliff alcove with rock walls effectively makes the room a part of the cliff itself. It's like digging into the ground to take advantage of the cool in the summer and the warmth in the winter, but under the rock ledge they were also protected from the rain and snow and had much more thermal mass to buffer temperature extremes. Facing south, or southwest, as many of the cliff dwellings do, would allow the sun to enter the openings into the interior and also warm the stones, which would give off heat at night. During the summer, when the sun is high in the sky, much less sun would reach the buildings and they would remain cooler.

I got an indication of how well solid rock can modulate temperatures at another stop. On the outskirts of Moab, Utah is a 5,000 square foot dwelling blasted out of solid monolithic rock, called Hole-in-the-Rock. It is open for tours, so I checked it out and was informed that the temperature stays about 65 degrees F. all year round. Moab is at about 4,000 feet elevation, so it is a warmer climate than Mesa Verde, but even so the cliff dwellings must have been fairly comfortable most of the time.

I couldn't help but compare what the ancestral Puebloans have achieved with what I have been advocating about sustainable architecture. They score remarkably high! The rooms are very compact, often sharing walls with each other (which makes for less transportation of building materials and the adjacent rooms help keep each other warm.) The rooms are often stacked on top of each other (I saw as many as four stories), which again conserves space, materials, and heating energy. There is very little wasted space; even the tops of the pueblos and kivas were used for community activity.

Most of the cliff dwellings were oriented to collect solar energy. Even though they didn't have glass to keep the rooms cozy, they compensated by using quite small entrances and ventilation holes, which could be sealed with slabs of rock or hides when they wanted. Being built into the cliff face, they did not overheat in the summer. Because of these factors they were relatively energy efficient, requiring less wood for heating.

The materials they used to build with were definitely local and natural, being just the sandstone and adobe found in the area. Very little wood was used, just small vigas to support the floors of the various stories or the kiva roofs. What wood they did use was obviously not milled. Deforestation was likely an issue for these people, as it is for us.

I'm sure they recycled building materials as there is much evidence of remodeling over time. They most certainly built to last, as much of their work has survived some seven centuries without any maintenance. The Park Service has stabilized some of the structures, but they say only about 10% of what is there now has been done since the



natives left. In fact you can usually tell which work was done in modern times because it is much cruder than the original work, which was carefully carved with stone tools and then plastered to make very smooth, colorful walls. Most of the original colored plasters have not lasted.

They did not have enclosed greenhouses, for obvious reasons, but they did grow all of their food nearby, basically on the mesa top that was their roof. They also had domesticated turkeys (the feathers were used for making blankets) and dogs (which provided hair that was woven into belts, etc.)

With all of this sustainability, why were they unable to sustain their culture at Mesa Verde? As I mentioned earlier, the likely cause was a prolonged drought that made it very difficult to provide food for the thousands of people living there. This could be the final message from these ancestors: ultimately we live at the mercy of mother nature. They were able to move on to other places where streams provided water for their gardens. Where could we move if our climate becomes inhospitable or we have polluted the waters or poisoned the air or our great machines cease to run?


Green Home Building: Article about 7 Ways to Build Green

Seven Ways to Build Green

by Roselind Hejl

Green building is a design process that grows out of a connection with the natural landscape. It is a set of informed decisions that considers the site and materials to reduce the cost, maintenance, and energy usage of the home. Conservation is central to the green building approach. Green homes are healthier, safer, more comfortable, and cost less to operate. They connect people to the land and community around them. Here are seven green building ideas:

Build a passive solar design.

• Passive solar design for natural heating and cooling is practiced throughout the world under all climate conditions. As energy costs rise, it is critical to use building orientation, window placements, stone floors, roof overhangs, reflective barriers and other techniques to control natural solar energy.

• In warm climates, face the broad side of the house to the north or south, to avoid excessive heat gain as the sun rises and drops in the horizon. Use deep overhangs or solar screens to shield glass areas from direct sun. Avoid skylights or greenhouse rooms, because they allow too much heat gain.

• In colder climates, solar heat can be captured and stored in materials such as concrete or stone to be slowly released during the evening.

• An open floor plan optimizes the effect of passive solar heating or cooling.

• Doors and windows should be placed to catch the prevailing breeze and allow cross ventilation.

• Lower inflow windows and higher outflow windows keeps air moving, as hot air rises.

• A thermal chimney uses a hot zone, such as a glass cupola with windows or vents, to create rising air currents to pull air through the building.

• Double glass panes provide an insulating air space between the panes, reducing heat transfer.

• The metal oxide coating on Low-E (emissive) glass helps to keep solar heat out, and

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interior heat in.

Ventilate attic spaces.

• In hot climates, attic spaces can accumulate heat, transferring it to living areas below. AC ducts located in the attic will absorb this heat.

• In cold climates, moisture can accumulate in unventilated attic spaces, causing wood rot or mold.

• Continuous eave and roof ridge vents will create natural air flow through the attic. Air enters through the eave vents, and moves out through the ridge vents. As heated air rises, it ventilates the attic.

• Lighter colored roof materials absorb less heat.

• Reflective heat barriers on the underside of the roof deck help to reduce heat gain.

• High levels of insulation in attics and exterior walls is crucial for comfortable indoor temperature in all climates.

• Some research is being done on completely sealed, highly insulated attics.

Optimize your heat and AC systems.

• An oversized system will cool too quickly, and leave the room clammy. Smaller systems run long enough reach the desired temperature, and, at the same time, clear the air of humidity.

• A smaller system lasts longer, does not cycle on and off frequently, and costs less to purchase.

• Check for leaks in duct work joints, and around windows, doors, attic stairs, exhaust pipes, recessed lights, and electric outlets. Ongoing maintenance of central air systems is necessary to prevent air loss.

• Use programmable thermostats to regulate your energy usage.

• Use Pleated-Media Filters in AC return-air grills. This filter removes particles as small as mold spores from the air that is drawn back into the AC blower, keeping coils cleaner and improving the air quality in your home.



• Heat pumps on electric furnaces reduce energy use by drawing heat from outside air, using the same technology that air conditioners use to remove heat from indoor air.

• Check with your utility provider for free diagnostic testing and rebates for high efficiency AC systems, insulation, solar screens, and weather-stripping.

Reduce water needs.

• Native landscaping that is suited to the rainfall in your area is fundamental to building green.

• Keep as much native growth on your lot as possible.

• Water pervious materials such as crushed granite or open paving blocks allow water to percolate into the ground.

• Rainwater catchment systems use gutters and barrels to catch and store water that falls on roofs.

• Front loading washing machines use less energy and water. Some dishwashers use less water and have no-heat drying. Check water and energy usage before buying appliances.

• Low flow toilets and shower heads reduce water usage.

• Reduce water and fertilizer needs by re-cycling yard waste and leaves for use as mulch.

Use renewable or recycled materials.

• Consider decks made of waste wood and plastic, such as Trex or other brands.

• Medium density fiberboard (MDF), a wood product used for interior trim and doors, does not contain formaldehyde.

• Fiber-Cement siding, trim, and pipe materials (Hardie Board) are very durable, rot resistant, and fire retardant.

• Use locally produced, and easily renewed, materials when possible.

• Consider alternative building materials, such as rammed earth, straw bale or structural insulated panels.

• Concrete floors utilize the foundation material as finish floor, saving materials and



labor.

• Recycled wood floors are a very attractive re-use of materials.

• Bamboo floors are made from a rapidly renewable source - bamboo is a grass that can grow several feet per day.

• Hard surface floors do not hold dust, molds, and allergens, and are very durable.

• Use materials with recycled content when possible, such as cellulose insulation, Thermo-ply, and lumber composites.

• Plan for a place to re-cycle household trash, such as a storage bin in the kitchen, and holding bin in the garage.

Safeguard your site.

• Trees, vegetation and bird habitat on the site should be protected during the construction.

• Native trees, grasses, rock outcroppings and natural drainage can be made a part of your building and landscaping design.

• Reduce the impact to the building site as much as possible.

• Make sure construction waste is properly disposed of, especially paints and solvents. Do not allow them to be buried on the site.

Use safe materials:

• Use products that are biodegradable, non toxic, water based, and cold water compatible.

• Avoid products that contain dyes, ozone depleting chemicals, heavy metals, formaldehyde, or known carcinogens.

• Avoid solvent based finishes, particleboard, adhesives, some carpets, and other products that release volatile chemicals into the air.

• Look for green rated labels on carpets and other products.

• Remove old-style pressure treated wood when possible, especially in play structures.



Green building is an approach to design and construction that respects the environment and conserves resources. It is a common sense approach that is available to all home owners. Green building techniques create a more cost effective, enjoyable and sustainable home to live in.

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Roselind Hejl is a Realtor with Coldwell Banker United in Austin, Texas. Her website - Austin Texas Real Estate - www.weloveaustin.com - offers homes for sale, market trends, buyer and seller guides. Roselind can help you make your move to Austin, Texas.


http://www.weloveaustin.com/

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