Climate Issues related to Sustainable Building
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Q: I will be building a house in the next few years on my own property in the country (at last!) and I am very much in the mode of building a home which is natural and safe for us to live in. I have been reading a lot about straw bale and have just about dismissed it as a method of building except in dry climates. We are so humid here and I have heard of no strawbale building here except one house in Alabama. Is there any information about building environmentally in the retarded South. (SC).

A: Almost all natural building techniques, including strawbale, will work fine in humid climates if certain basic precautions are taken. Walls need to be protected by wide eaves, foundations need to be high and dry, and the walls should be breathable so they don't gain moisture and hold it.

Q: I am in the process of designing and building a home on a tropical island (Saipan, 15.5N, 145.5E, US Commonwealth of the Northern Mariana Islands, near Guam). I would like to use sustainable architecture and building principles, and have done a fair amount of studying architectural principles for hot humid climates coping with earthquakes, typhoons, and 90" rain each year. I have so far come up with a courtyard plan, "U" style house built off the ground. My question is this: how can I build using sustainable architectural principles, when all of the building materials are brought in, and cement is the only economical medium? Thanks, great internet site, very helpful!

A: I have a couple of questions about your situation on Saipan. 1) What are the temperature variations over a year? Do you basically just need protection from the weather, or do you also need to significantly moderate your temperature? 2) You say that all building materials must be brought in. What sort of soil do you have? Sand, clay, crushed shells, silt? What sort of vegetation is available? Shrubs, trees, grasses, reeds, bamboo, etc.?

R: The temperature variation here is quite small throughout the year, usually from 80 to 90 in the daytime, and 75 to 80 at night. What varies is the humidity, in the monsoon it is very high. The prevailing winds are east-northeast, about 45% of the time. We have time periods when we have the doldrums, usually twice a year, March/April before the rains, and October before the winds turn around and come from the west. I'd like to build using those figures to capture as much wind as I can to flow through the house. As for local materials, they do mine the coral aggregate for roads and other projects, but no one locally makes lime out of the coral. We have a lot of sand, but it is not used for construction due to erosion concerns. There is bamboo grown here and there, mostly as an accidental plant left in the yard that grew out of control, but nothing for commercial purposes, and no companies import it that I have been able to find There are a lot of ironwood trees here (aerially seeded after WWII, as the US bombed Saipan down to bare rock), but I can find no one who processes them or grows them for the local construction market. Clay is not a medium I have heard of being used, although we have it here. Most imported wood has to be heavily treated to last more than a few years. Saipan's bugs and termites are very healthy and hungry. As for growing vegetation, everything grows very fast. In 4 months, my banana trees went from invisible to 6 feet tall. Basically, Saipan is in the 1950's in terms of conservation, renewable building, and climate responsive building design. Most of the construction companies are run by Filipino's, and the Philippine construction business is not noted for its conservation efforts or its knowledge of "green building." They build everything with the cheapest cost and quickest build time in the forefront of all planning. So, any help you could give would be greatly appreciated. Thanks very much.

A: It doesn't sound like the folks who run the infrastructure there are very enlightened. I've put a little thought to your question, and come up with this suggestion; it would potentially give you shelter that could survive virtually any wind, rain or insects and would be on the cooler side, with breezes when available. Also it would be very inexpensive to create. What I suggest is something similar to what I have done, using earthbags filled with the soil from your site to create a dome or domes, which would then be plastered with a cement stucco. A vapor barrier could be placed over the domes before they are plastered. Some portions of the dome could be bermed with more soil to help moderate the temperatures. Wind catching towers can be employed, similar to what is used in the Middle East, to direct the wind into the house. The earthbag page at www.greenhomebuilding.com has a lot of information about this type of construction, including books and videotapes.

R: Thanks for the info about the building style. Unfortunately, I won't be able to get a building permit for that type of structure. The building permit people, AKA the neanderthals, don't believe that earth-filled earthbags will be sufficient. They believe that not even if the earth was highly sterilized, like potting soil, would it be any good, because the humidity would cause mold and growth, and the rains would eventually enter the structure and cause problems. I wouldn't have the faintest idea how to sterilize that much earth, and it wouldn't matter anyway. They are also concerned with the loss of topsoil used in the earthbags, and despite my suggestions to check out your website, my requests fell on deaf and dumb ears. Back to the drawing board. Cheers!

A: I'm sorry to hear that they are being so obstinate about this. You wouldn't necessarily have to use top soil. It could be other sandy soil or gravel or crushed shells... Also the soil could be mixed with portland cement, so that it would become what they call soil cement, which would eliminate any problem with moisture causing mold or growth or other such problems. Don't give up; I think this type of building could solve a lot of problems around the world. It has been permitted by code officials in the United States, and tested for earthquake soundness, etc.

Q: My husband and I live in Omaha, Nebraska. What sustainable home building type is most appropriate for our climate. (extreme cold to very hot and humid)?

A: In this kind of climate you want to have a well-insulated house to protect you from those extremes. Nebraska is the historical home of straw bale building, so this approach has been tested by time http://www.greenhomebuilding.com/strawbale.htm. Other approaches you might want to investigate would be earthbags (such as my house), underground or earth-sheltered building , or AAC.

Q: I would love to hear more of your building ideas as down here on the coast of Texas we have to build up off the ground and in wood. Main problems are Wind and excessive sun, termites that grow fatter by the day as they munch through endless planks of wood. Most buildings here rely on A/C and homes are far from being energy efficient.

A: The best way I know to combat the problems that you mention is to build into the ground with earth. This gets you out of the wind and sun, keeps you cool, does not appeal to termites and can eliminate the need for air conditioning. Earthbags are a good way to go.

Q: I live in Puerto Rico. I'm studying Environmental Engineering and my dream is to be able to live in an environmentally harmonious home. I was wondering if the houses built from the materials of sustainable architecture are hurricane proof, since Puerto Rico is an area of very high predisposition to this type of natural manifestation. If the materials are not hurricane proof, I would then like to know what other options I have. Thank you for your time and attention, and most of all, your love for nature!

A: It is hard to generalize about how natural buildings hold up to hurricanes, because there are so many variations in materials, designs, and techniques of building. I would say that it is certainly possible to build naturally and sustainably in such a way as to withstand the force of nature...in fact I consider that to be one of the main tenets of sustainable architecture: that buildings should be built to last!

For instance, the house that I built for myself is composed of earthbags shaped into domes and I dare say that it would hold up to hurricane winds with little damage (maybe some broken glass?) Most other methods of natural building, including cob, adobe, rammed earth, strawbale, and cordwood should withstand storms, if proper attention to engineered details is adhered to. The most vulnerable element to designs built with these materials would be the roofs, which would have to be fastened to the walls extremely well. That is one reason I would recommend domes or earth-sheltered designs in your area.

Q: I just bought land in the rainforest of Big Island, Hawaii. I wonder if you could recommend materials that would suit building in a humid, warm environment, and what plan features you might recommend to have shelter while at the same time creating a feeling of being open to the beauty of nature all around me. Is there a site you recommend I visit, or plans for tropical environments?

A: The typical approach to building in a warm and humid environment is to build off the ground and provide lots of ventilation. Since the climate is rather moderate, there is not a great need for insulation...mainly a roof, simple walls, and a floor. I have wondered about going in the other direction: digging into the ground to combat the heat. You would still need to provide good ventilation to control humidity, and carefully arrange window openings to keep your views, but this can be done.

Q: What kind of materials would you use for building a house in earthquake land?

A: There are many materials and designs suitable for earthquake country; partly it depends on what materials are available to you. Wood-framed houses can often withstand considerable shaking if they are well-built, but wood is not so easy to come by any more and using it tends to deplete the forests. A material more readily available is the soil beneath your feet, which can be put in earthbags and used to build domes that can withstand earthquakes. You might look at some of the pictures and read the information available at greenhomebuilding.com/earthbag to get some idea of how to proceed.

Q: We are a young couple who live in the Caribbean island of Puerto Rico. We would like to experiment with some kind of eco-building here in this 'Tropical rain forest'. What kind of eco-building techniques do you suggest that we look into?

A: In many ways tropical regions provide much more latitude in choice for design and materials concepts. It often isn't so necessary to focus on insulated structures as the only appropriate mode, so that creates more options. You could really utilize any of the materials listed at this site and create a comfortable home. I would suggest that you carefully look at using local materials, since that is the most sustainable, and usually the least expensive. I am not too familiar with what is available in Puerto Rico, but I would suspect that bamboo, stone, cordwood, and earthbags might be good choices. As for design, I would study the local vernacular architecture so see what has worked well historically; often, light-weight, airy designs are utilized. It would depend on the water table and susceptibility to flooding whether underground or earth-sheltered designs would work. If keeping cool enough is the main concern, this strategy may be a good one.

Q: I want to build a small, healthy home in Newfoundland, Canada. What kind of natural shelters would be an option here, cold winters -10 C average, snow, lots of wind, rain, humidity? I am single mom and need to build inexpensively.

A: You have many options that would likely suit your needs. You definitely want a well-insulated house in that climate, and a design that provides at least some passive solar heating when the sun shines. I would recommend investigating strawbale, cordwood, or earthbags as possible techniques to explore. The cost of building depends on many factors, but can be done fairly cheaply, especially if you do some of the work yourself and shop carefully.

Q: How do green house construction methods vary across the country when considering things like climate?

A: Being sensitive to the local climate is very important with green building, and this is primarily a matter of good design, such as utilizing passive solar designs  that function well for the specific location.

Q: I am having difficulty understanding what homes are best for hurricanes, fires and tornados.  I live in Florida and am really having difficulty finding out this info. Any ideas?

A: I would say that the very best homes for the kind of hazards that you mention would be underground, earthbermed, or earthsheltered homes, since they essentially place the bulk of the home out of harm's way.... see Keep Your Cool. Other forms that do well in these situations are domes constructed of concrete, like the Monolithic domes or perhaps earthbags homes, like what I built.

Q: What inexpensive, sustainable, safe home design would you suggest for disaster victims, such as, the tsunami people, New Orleans people, etc? Could the home be constructed quickly and expanded to more rooms? It seems that past suggestions from other home designers have involved more money than victims can afford or complexity of design that takes too much time and resources. The idea is to provide many, safe, small, inexpensive homes in as little time as possible, in a wide spread disaster. I am familiar with the Safe-R home design that has merit.

A: One emergency earthbag design that is inexpensive and fairly quick to build is outlined at emergency shelter. It may not be that easy to expand...

Another way to go is with SIP's, such as the small design at http://dreamgreenhomes.com/plans/2manhut.htm . This concept would be easier to expand upon.

C: I worked with the Red Cross in counseling victims of the tornado destruction in Eagle Pass, TX a couple months ago. A couple of effective techniques to help the victims was removal of destroyed housing materials to get to the foundations. Secondly, community centers were turned into victim centers for food and sleeping cots. The Red Cross and Salvation Army were great. FEMA was again not so helpful and missing from work areas when I was there. Many of the victims had little to no resources for re-building, but neighbors worked for free and donated materials. For some reason, I am very compelled to find better ways to provide housing to help the victims.

Q: We are helping to rebuild the gulf coast of Mississippi and I would love to speak with you about your opinion.

A: In general my opinion is that it is foolish to rebuild in places that are inherently vulnerable to flooding (such as most of New Orleans); why temp fate, especially with the prediction for increasing sea levels and ferocity of storms? Rebuild on higher ground in areas that are not subject to inundation. Then, I suggest that you follow the guidelines listed at this website,  where 13 principles of sustainable building are outlined. There is a lot of leeway in doing this, depending on local resources, life styles, finances, codes, etc.

Q: I'm an architecture student from the Philippines. Since our country encounters several problems on flooding yearly, what planning measures (for example, in houses) shall we take to reduce property damage? Is there any solution to this in a sustainable way, aside from elevating the structure to a certain height? What innovative, yet eco-friendly materials shall we use to attain a flood-free house or structure?

A: First of all I would advise that you consider using only building materials that are not adversely affected by moisture, so that even if the home does get flooded it will not deteriorate from the experience. This generally means the use of masonry or mineral materials, such as stone, bricks, lightweight concrete, etc. One method of building sustainably that is gaining favor around the world is earthbags. I have an entire website about this (www.earthbagbuilding.com) with lots of information about this technique of building.

Another concept for flood mitigation is shown on this page.

Q: I have 3 lots in downtown Klamath Falls, OR with 3 geothermal wells on it and 42 acres of forest, bedrock & range land. We would like to green build offices & greenhouses for farmers' market/grocery community retail space to lease for our non-profit organizations on the downtown piece & a small farm multifamily dwelling on the 42 acre piece.

Can't seem to put all the information together to build sustainably on either piece & thought your expertise having lived near Ashland could help with site design & architecture & design could help us out. Any heads up you can give us would help.

A: This sounds like some very nice property you have in Klamath Falls! With all of that geothermal potential it would be a shame not to take advantage of it, for space heating, greenhouses, and/or relaxation (if it is hot enough). Klamath Falls is higher than Ashland, and very cold in the winter, as I recall...so the geothermal should be very welcome this time of the year.

There are lots of options for green building, as you know I'm sure, but the first thing is to decide what you need and get some ideas down on paper for what it might look like. I wrote an article about building your dream green home, that might help you with this.

Did you find my site with the stock green home plans: dreamgreenhomes.com?  This might help you think about your options as well. One of the designers (Touson Saryon) at this site lives in Mt. Shasta, not too far from you, and I'm sure he would be interested in helping with your design challenges. He specializes in strawbale plans, but can design for other materials as well.

Q: Is there a certain environment or region that these homes do better in? I really enjoy the earth sheltered home (above ground).

A: You can build an ecological home anywhere in the world. The specific plan needs to suit the climate of the place where you build it though. For instance, a passive solar home needs to be adjusted for the need there is for this kind of heat and the direction of the sunlight.

Q: My dream is to build a natural house, a rammed earth or a cob house.... in Taiwan, as that's where I plan to retire and my husband's family is. In the town, called Taitung, on the east side of the Island. Taiwan's east coast continuously has earthquakes, usually around 4 -6 on the scale. And typhoons which hit the Island's east coast first before traveling onward. Which would be better, rammed earth or cob? Also Taiwan is a sub tropic climate and 3 months of the winter is cold. And there are no furnaces in Asia! Would a natural house be warm enough or warmer than a traditional modern house?

A: From my own perspective, neither rammed earth nor cob would be ideal in a really cold climate, because neither provides insulation against temperature extremes. In fact both cob and rammed earth are nearly the same, with cob being perhaps slightly more insulating because of all the straw that is used to make it.

If you want a truly comfortable home during the entire year, you are better off building the shell of the home with a more insulating material, like cordwood, strawbales, or earthbags filled with volcanic stone or rice hulls. You can use elements of cob or rammed earth on the inside to provide thermal mass. This combined with a good passive solar design should provide a very comfortable home in your climate.

Q: I am doing a project at school to investigate green building design. Our school is currently going to build an performing arts centre along green principles. For our project we have to design a structure or system to be used in the building that is environmentally green, and to conduct an experiment relating to the idea that we have chosen. As part of our project we have to consult an expert in the field. In order to answer my research questions, I did some internet research and selected 5 construction materials. They are conventional clay brick, strawbale, wood, rammed earth and adobe.

1. What environmentally friendly construction materials are the most energy efficient to make and to use in construction?

Adobe uses the least energy to make and utilize in a building. Strawbale is probably next in line in terms of embodied energy. Rammed earth might be next, since it takes a fair amount of energy to ram and often some Portland cement is used to stabilize it. Wood might be next, since there is usually a lot of energy used to harvest, mill, and transport wood. Conventional clay bricks use a lot of energy to fire and transport.

2. Which construction materials would keep the building the coolest, thus saving the energy that would be used to cool the building?

Strawbale is undoubtedly the winner here. Wood would be next, since it is a moderate insulating material. The other three are about tied, since all of them are really "thermal mass" materials and are poor insulators.

But the real answer to this questions is that the best solution is a hybrid of several of these, so that the shell of the building insulates the structure, while some thermal mass material is incorporated inside the house to keep it at a constant temperature.