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Janine Bjornson is a natural builder, practitioner and educator. She began her career in natural building when she trained with The Cob Cottage in 1996. Since then, she has taught over 50 workshops in Canada and the United States, from east to west. Her passion for building with natural materials bloomed out of her love for the earth, in conjunction with her concern for diminishing ecological resources and toxic buildings. As a result of this, Janine has devoted the last decade to immersing herself in the world of natural materials and the knowledge of how we can shape dwellings that are healthy, healing, inspiring, and beautiful. She has developed a penchant for natural paints, and plasters and loves the concept of “naturalizing” any kind of home. She loves to share this knowledge with others and this is evident in her enthusiastic teaching style. Janine has assisted in organizing 2 Natural Building Colloquia and she has presented at 3 of them. She teaches the natural building component of New College of California's EcoDwelling program. She lives in Sebastopol, California.

Q: I need to use natural materials because I am chemically sensitive. What could I use to insulate my 1926 frame house? I would like to do it myself, inexpensively. Our summers are extremely hot, but winters are 10 below zero.

A: I realize that everyone that is chemically sensitive has a different degree of sensitivity so make suggestions and you will need to see if you are compatible with these options. I would suggest checking out the recycled denim insulation called ultra-touch. It is made by bonded logic 480 812 9114, or check out ''bonded logic.com" to read about it first. You may also be able to use the blown in cellulose insulation. There are brands available at most local hardware stores, it is inexpensive and they often let you use the blower for free when you purchase the insulation. However, it would not give you the r value that would be the best option given your temperature swing. There is one brand named "cocoon". Other than those two options on the market you may have to get more creative. In Britain and New Zealand they sell wool insulation batts. You could probably import them for a pretty price. Some people have made their own versions by acquiring wool and having it cleaned, then carding it, and insulating with that. That may be the most affordable option for wool that you would have.

Q: I am looking for a material to insulate a concrete floor slab used as a thermal mass. We are utilizing natural materials wherever possible and would like to continue doing so. We are building at very high elevation, 9500 ft. We have have hot summers and very cold winters(-25F).

A: You dilemma is a tricky one. One of the systems that several people have tried to do is the "sandwich method" in which straw bales are used in between concrete layers to insulate. There have been some problems with this method unfortunately. I would suggest you read the section in " The Serious Straw Bale" published by Chelsea Green, the authors are Paul Lacinski and another man I cannot remember right now. It discusses some of the research done on this method. To my knowledge there hasn't been too much done that's completely natural. The danger of course is water. You might think about mixing in something like a layer of perlite mixed with some fly ash or a small amount of concrete to up the insulation value. It isn't as pure as something like straw....but the choices are limited.

A: (Kelly) I live at over 8,000 ft. in Colorado, and I insulated my adobe/flagstone thermal mass floor with about 6-8 inches of scoria, a crushed volcanic rock that is locally available. Any light-weight volcanic material would probably work, and if this is not available, then you might consider using perlite or vermiculite for this purpose.

Q: I need to insulate a couple rooms in my house. I am interested in wool batting but the only company I found said that wool has to be treated to avoid moths. They soak their wool in something called Boron. Can you tell me more about this, what boron is and if it is a pesticide, what is a more natural way to insulate?

A: Boron is nonmetallic compound occurring naturally only in combination, as in borax, boric acid etc., Boric acid is a Boron compound. Borax which you may be familiar with in the form of a laundry additive known as "Twenty Mule Team Borax" is obtained from naturally occurring Borates. These are mined in the United States in the Mojave Desert. They are also found in Turkey. The Boron compound "pentahydrate" is used to make fiberglass insulation. ELEMENTAL Boron and the Borates are not considered to be toxic. They do not require special handling of any kind. I would suggest that you find out what kind of Boron is used with this wool insulation to be safe. It is only the more exotic borates that may be toxic. All this aside I would like to suggest something else. There is another option on the market for insulation. If you are interested in using pre-manufactured insulation batts you can now get them made from recycled cotton (mostly blue jeans). There are NO warning labels on this product. You can contact the company to see who distributes this product in your area. (see: bondedlogic.com)

You could also check out Cellulose Insulation, there are different brands available ( I can only recall one called "Cocoon" presently).This is recycled newsprint that uses Boric Acid as an additive for fire-proofing the material. It is most likely that Boric Acid is what they are using for the wool insulation as well. Cellulose insulation most commonly comes dry. You purchase bales of it from the hardware store, and insert it into a hopper which blows it dry into the wall or roof cavity. There is a wet version but it is less common.

Q: We are in the start-up phase of developing a natural timber frame cottage business in the interior of British Columbia. A big challenge for us is to offer an affordable, natural insulation. Our walls consist of stacked timber, so wool rope can be used to seal between them (small quantities). However, the ceilings and gable ends require something more affordable. I am very interested in light straw-clay and am wondering if anyone is producing light-weight straw clay insulating blocks or panels. Also, in your opinion, is the market for natural, sustainable homes growing?

A: Strawclay panel manufacturers appear and disappear regularly on the North American market. There are no consistent producers to produce gable end in-fill panels. You may have to produce them yourself. Habib Gonzalez of Sustainable Works in Nelson, B.C. regularly uses straw bales in the gable ends in both load bearing and beam systems. Kim Thompson, a straw bale builder from out east uses custom straw bales or bale flakes in gable ends. You can produce your own custom light clay straw insulation or use the bale options. However, there are some things to keep in mind. Clients and colleagues that are firefighter's of Habib's agree that bales can be dangerous in the ceiling. If the bales come down when there is a fire, it presents a hazard to rescuing people in a burning building. Also, in a recent addition, of The Last Straw the author's calculations state that bales are too heavy to be effective insulation for the amount of material it takes to support them. Aside from those straw options, you may want to consider recycled paper insulation. This is commercially available. It is made from recycled newsprint and uses borax as a fire retardant. You can use this in shallow pitched roofs, or in areas where it can be contained. This is a fairly inexpensive option.

I would also like to make a plug for the cotton blue jean insulation. There is a company making batts of this non toxic insulation out of Chandler, Arizona. Unfortunately, it is not cheaper than batts of fiberglass yet. However, it is nice to use and it is rated for fire. The product is called "UltraTouch", by Bonded Logic. Bonded Logic (480 812 9114 bondedlogic.com). I am personally looking forward to the day that there is wool batt insulation on the market like there is in Britain, and New Zealand. There is plenty of wool out there, we simply need to get it manufactured.

To answer your second question regarding the Natural Building market.... Yes, I believe the market is growing for natural, sustainable homes. I have really noticed an increase in education of natural building techniques over the last eight years and I have noticed a movement for many people to begin using these techniques in their own homes in the last three years. As our dwindling resources become more obvious to the mainstream public, as chemically sensitive people begin to multiply, and as more and more people begin to read magazines like "Natural Home", the literacy and the demand of these home increase. I can only imagine this trend increasing due to our current state of affairs regarding logging issues or health concerns. Beside those dry facts, natural buildings are gaining more popularity due to their incredible beauty, along with the complex but extremely obvious psycho-emotional response that human beings experience when entering one of these buildings. In addition, I would like to say to you that I would include stacked timer in this category. For me, a natural building is a building that is using appropriate and available materials that are pertinent to that particular climate and bio-region.

Q: I am considering spray foam for my home insulation. It appears to be the most energy efficient way to go. Could you advise me on this.

A: (Kelly) It is true the spay foam insulation has the highest R-values of any insulation around. The problem with it from an environmental viewpoint is that it has more embodied energy than other choices, and it can be quite toxic, especially if it ever catches fire.

Q: I have interest in trying to make my own wool insulation. I have a source of wool and would like to know how I might process it to make it usable. Do you know anyone who has had success with this process?

A: Over the years I have heard of many people that have dabbled in using wool for insulation. I cannot say that I have heard of one particular technique that is tried and true. I will give you the most clear method that I have heard of as follows:

1) Clean wool. This means that you need to remove any dirt, debris, and lanolin. There are various ways to clean the wool but you want to make sure that the method you choose does NOT felt the wool. Use COLD water to clean the wool, not warm or hot. You may try anything from putting the wool in burlap sacks and sinking them in the river with the cold water rushing over them to clean the wool. Or you may put the wool in front loading washing machine set on the 'gentle' cycle. Do NOT use the top loading machines or you wool may turn to felt. You may use an industrial detergent to clean the wool in the machine. You will know that the wool is clean and the lanolin is removed because the wool will feel soft like a wet wool sweater and your fingers should not stick together after touching the wool. If your fingers feel sticky, there is still more lanolin in the wool that needs to be removed.

2) Treat with Borax. You want to treat the wool with Borax (commonly sold as "20 Mule Team Borax Laundry Additive") to repel insects. Borax is also used as a fire retardant. If you are using the washing machine to clean the wool you could add the Borax instead of fabric softener. Otherwise dissolve Borax in hot water to make a solution and spray on the wool as you lay or hang it to dry. Do not rinse it out. Unfortunately, I haven't been able to find out how much Borax you should use.

3)Card the wool. You now need to card the wool (when dry) to fluff it up creating air spaces between the fibres which will give it loft and greater insulation value. Remember, things that are insulative are light and fluffy like a down quilt. You may be able to find someone with a carding machine, otherwise you will need to card it by hand.

4) Make batts.You can now get strips of kraft paper to attach the wool to. This will hold the wool in place when you put it in a wall cavity. If you are placing it between 2 x 4's as in standard construction practices, you will want to cut strips of kraft paper 16" wide and as tall as your walls (for example). Spray the kraft paper with adhesive and lay down your carded wool onto the kraft paper. It is important to use some kind of system like this so that the wool insulation will not slump and settle in your wall. If it does, you will lose the insulation value that you were trying to create. You will also have air spaces at the top of your walls that will transfer heat or cold through the walls.

Q: I'm in my attic trying to organize it. The insulation in there is from 1949!!!! When I'm in there working, I'm realizing that I'm coming out with fiberglass in my pores (even though I'm not touching the old insulation). I am looking to re- insulate this old attic. I've read some articles that say to insulate over the old insulation. Is this a good idea? I've also seen on HGTV that there is an insulation product out there that is "denim insulation". I'm thinking that this is a healthier way to go. Have you heard of this product? If so, do you know where I can purchase it?

A: (Kelly) There is a company making batts of jeans insulation out of Chandler, Arizona. The product is called "UltraTouch", by Bonded Logic. Bonded Logic (480 812 9114 bondedlogic.com). I also would recommend leaving the old insulation there and adding new to it, for several reasons: it is good to recycle material, especially if you don't have to work to do so; taking out the old fiberglass will really get it into your pores; and the more insulation up there the better. You might read about insulation at: naturalbuildingQandA.htm#insulation.

Q: I was wondering if you had any advice on how to renovate a mobile to make it more natural, and also to fix the problem of them losing a lot of heat.?

A: (Kelly) Mobiles tend to be so small inside that adding thickness to the walls in that direction is usually not such a good idea...better to try adding insulation on the outside, possibly with strawbales, or earthbags. This approach requires a lot of thought and care to make sure that a new roof covers them and they are on a good foundation (if using straw).

Q: I am investigating the possibility of using pumice or using something natural which can be used as insulation. We have had too many bad results with man-made materials, i.e. inhalation and lung maladies, that if we could use pumice or scoria or heat the correct rock-type into a form which can be used for insulation in construction, then possible we'd have a heat-resistant, light-weight, sustainable product which could save a lot of trees and aid in sustainable development. If you know of links which explain the possible process of making this type of insulation or the feasibility of it, I would be delighted.

A: (Kelly) One natural product that you might consider is perlite or vermiculite. See www.schundler.com for more information. Another possibility is discarded rice hulls. See earthbag.htm#ricehulls for more info.

Q: I am a musician in New York and I am building a soundproof room in my basement-the soundproofing engineers I have consulted all recommended vinyl, vinyl foam, mass-loaded vinyl, etc. to line the walls and ceiling and acoustical caulk to seal the holes, but I have heard such bad things about vinyl that I am searching for a more ecologically safe solution.

A: I forwarded your question to a friend of mine (Tim Wiedenkeller) that is a professional musician and studio technician as well as natural builder. Here is his reply:

Soundproofing can be challenging. I'm not sure about vinyl - maybe you actually mean foam which is a common solution - but it's foam. I've seen lo-tech solutions such as hanging rugs around the perimeter of the room, obtaining old mattresses and fastening them to the walls...old carpet/padding can be out-gassed-out to a high degree which can be attached to walls, baffle-shapes, etc. Hmmmmm. Not an easy one. Professional studios build an extra layer of walls, floors and ceilings - often floating these installations. I haven't seen any natural solutions apart from the obvious - using straw-bales.

 

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I specifically disclaim any warranty, either expressed or implied, concerning the information on these pages. Neither I nor any of the advisor/consultants associated with this site will have liability for loss, damage, or injury, resulting from the use of any information found on this, or any other page at this site. Kelly Hart, Hartworks, Inc.

 

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