Do adobe homes really work in all climates? – Book review

Katherine, I think you sum up the points very well relative to 320 sunny days making adobe work in your climate, and the lack of that sun meaning that it doesn't work in Vermont. I just don't see it happening without insulation, and if you're going to use insulation anyway, why does adobe make sense for the exterior wall? There are plenty of vapor-permeable insulation materials, by the way. Open-cell foam, cellulose, etc.

New Mexico has an enviable and terrific unbroken tradition of earth construction. At the same time, adobe and other forms of earthen building have come a long way, and are now fully integrated with modern methods and standards. I'd like to clarify a few points from the above post. Moisture: You can successfully use adobe in any climate. It doesn't make any difference whether it rains one day a year or 100 - rain can't leak in one of those times. And with modern construction materials and methods, it doesn't. Thus, it makes no difference whether you are using wood, earth, or straw: moisture can't leaks in, and it doesn't. The path of the sun, or even if it shines at all, has nothing to do with moisture control. Moisture must be controlled in all forms of construction, and is controlled in the same way (reliably!) Most all adobe bricks contain around 5% cement by weight for stabilization, but that was a stopgap measure started a couple decades ago; now we just build houses better, which definitely works. Traditional adobe certainly was (and can still be) done using entirely different principles than I just iterated. But traditional stick-framing has changed just as much. So I must note again: modern methods have totally changed how we build any kind of house, and these principles apply exactly the same no matter what the house is made of. We make the house as waterproof and airtight as we can, and then we ventilate it. If you do that, any material will work in any climate; if you don't, no material is guaranteed to work well. Thus, the real crux of adobe or not, are simply these two questions: 1. Can you make the bricks near where you live? For this you do need sun! And the right kind of dirt. Adobe companies definitely ship their bricks, but that quickly becomes a financial, environmental, and aesthetic stretch. 2. Do you have a large diurnal range of temperature? Adobe is super-high mass, which is a total waste of money if you can't take advantage of it, when all that is needed is high R-Factors. Indirectly, moisture actually does matter here, because low humidity means high diurnal range. In summary, earthen construction is done in arid climates, not due to concerns about moisture leaking in, but because you need clear skies to make the blocks and raise the temp in the day and drop it at night. (And because there are no trees :-)

Hello Everyone, First of all, I want to thank you for an interesting discussion. The topic of how to improve the insulation qualities of earthen walls has been in review for the past few years. My personal experience with adobe has been in areas where the sun does shine, even if just for an hour a day in the winter. We often made bricks in the rain and covered them tightly with plastic to dry. Adobe bricks don't necessarily need the sun, but they do need to be protected from moisture and allowed to dry out. However, when building an adobe home in colder, cloudy regions, insulation is often needed to make a comfortable home that uses the minimal amount of additional heating. One great adobe mentor of mine is Quentin Wilson of the Adobe Association of the Southwest in New Mexico. He states that "strange things will happen if you add insulation to the adobe. The wall will perform better than the sum of the two R-values." He calls it phantom R's. This is because the adobe is not an insulator but a capacitor and conductor that mimics insulation in certain situations. When you couple capacity with resistance you get more resistance than expected in a non-steady state situation. Electrical engineers understand this as capacitive reactance or a band pass filter. Considerable research has been done in many parts of the world on this topic and I am happy to share with you some of the conclusions. Most importantly, the use of passive solar design is essential to utilize the sun's energy to heat the home in the winter. This may require reducing the eaves to allow the winter sun to enter the home. Secondly, it is suggested that home owners insulate their adobe walls at least on the side facing away from the sun; this would be the north facing walls in the Northern Hemisphere or the south facing walls in the Southern Hemisphere. One recommendation would be to attach 2" battens, insulating with wool or another natural, breathable material, and cladding. Many people also use 2" of polystyrene with plaster over to increase insulation. Dow Styrofoam Utilityfix xps is a closed cell foam and will not loose its R-value to moisture uptake. Another good option would be to use conventional timber frame construction with insulation and cladding for the exterior walls and interior adobe brick walls for thermal mass. These homes make use of all the good qualities of earth, such as regulating humidity levels and neutralizing airborne toxins. The exterior walls do not require large overhangs, thus are suited for passive solar design. Lastly, you can make adobe bricks with improved insulation values for exterior walls. These bricks include light aggregates, such as untreated sawdust and paper pulp, and when combined with earth increase the insulation value. The exterior side of these bricks walls require 3 coats of plaster for added protection against moisture. Ultimately, what makes adobe homes suitable for colder climates is when they are designed for the sun. The excellent thermal mass qualities allow the walls to slowly retain the heat and slowly release the heat into the home. As for all green building products, some are more suitable to certain regions, and it may be difficult to acquire and produce the necessary adobe bricks in some places. But studies show that adobe bricks made on site have the lowest carbon footprint of all building materials, and this should be considered with evaluating our building products. I like the idea of including an additional chapter on insulating adobe where this topic can be discussed in depth with details and examples of the ideas mentioned above. Hopefully this information has shed some light on alternative ways to improve the insulation qualities of adobe brick homes. I do believe that adobe brick homes can be suitable for all climates, when the appropriate design is applied. Again, thank you for this lively and interesting discussion. Lisa Schroder Co-author of Adobe Homes for all Climates

There are earthen-walled homes in cold and cloudy north country; here's some photos of ones built in the 1800s in the Finger Lakes area of New York, still going strong, that I took in 2004 - http://www.potkettleblack.com/potkettleblog/crypt04/000167.html Richard Pieper of Jan Hird Pokorny did terrific sleuthing into these places some years ago -http://www.eartharchitecture.org/uploads/EuropeanTraditionsinEarthenCons... I'd build with earth in this part of the world (two towns north of the BuildingGreen offices in Vermont)... but it would have a full envelope of insulation on the outside.

Eleanor, You can use adobe bricks for thermal mass interiors of the exterior walls, but you'll also need an interior air/vapor barrier to meet Canadian codes and to protect your structure from moisture damage, so you'll probably have to place the adobe inside of a drywall surface. But what you need most in your climate is lots of insulation and an air-tight building. Earth is a miserably-poor insulation. I would recommend insulating within the wooden frame and adding additional exterior insulation under the new siding. I would look for a competent builder who understands the mechanics of heat and vapor movement.