Welcome to StrawBale.com
My name is Andrew Morrison and welcome to my straw bale building site dedicated to anyone interested in building their own straw bale house. If you are brand new to straw bale or are a straw bale construction specialist there's something for you at StrawBale.com.
Click here if you are NEW TO STRAW BALE BUILDING and want to know the basics about straw bale construction.
I have a ton of information for you including: photo gallery, step-by-step instructional videos, information about straw bale workshops around the world, free straw bale articles, free straw bale social network, and a full straw bale building blog.
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I just got an email from someone who plans to install his windows and doors the following way. I think it is an interesting idea as it will provide for very good compression of the bales and a very quick construction of the walls. This is in line with how additions can be added to existing straw bale homes. I always suggest that if people have specific intentions to expand later on down the line that they plan for the expansion by leaving electrical out of the area where they plan to cut in the new hallway.
Check out the idea sent in via email and let me know what you think about it.
1. The spaces required for windows and (over sized) doors are not left open but
rather the walls are built as full walls with no spaces. The lintels for the
doors and windows are however, put into place.
2. Once the walls are at roof height, wall plates are in place and the bales
have been compressed and have settled (some 2 days or longer after
compression), the door and window spaces are removed via chainsaw or other
appropriate method, from below the lintel.
3. The sides and bottom rails of the door/window spaces are immediately put
into place and the sides are attached to the bale wall by pinning through the
timber into the bales with wooden dowels. Care will be take to ensure that any
part-bale section within the space that are small enough to fall out, are kept
in place. This should not be a problem however, since once the bale compression
has taken place, the compressive force should keep the straw in place even after
4. The pre-made window can then be attached to the frame or constructed within
the frame from scratch. Doors are made to fit the space.
I got an email the other day from a company that works with Japanese trowels. These trowels are amazing, especially for detail work. The shape and flexibility of the trowels makes them perfect for working with detailed plaster jobs.
If you have areas with small, hard to reach spots, like inside wall niche for example, you might consider using the mini trowels shown here. They are perfect for some of the smaller areas found in bale homes. Of course, I still love to use yogurt container lids for soft curves, but you can’t plaster an entire niche very easily with a yogurt container lid!
If you are interested in purchasing trowels like these, please visit www.LanderLand.com. Beyond the trowels shown here, they have some really cool inside and outside edge trowels and edgers. The trowels themselves are a work of art and they produce beautiful plaster jobs as well. Keep in mind that the Japanese are known for their attention to detail and that has not slipped past these trowels.
Getting a straw bale home appraised is one of the harder aspects of construction. Why? Because there are not very many, if any, comparable sales of straw bale homes out there. So how do you jump this hurdle? There are a couple ways to do it.
The first and most promising way is to make sure the appraiser knows why there are no comparable sales near you. The reason is that people who buy straw bale homes don’t often sell them. This is not because they are hard to sell but rather because they are such amazing homes that people don’t want to leave. Most of the homes I have built over the years are end user homes. This means that the people plan to live in their straw bale home until they die. At that time, the will likely hand the house down in their will to their children. I’m serious, bale home owners love their bale homes! The problem for you and me is that because they don’t put their homes for sale on the after market (meaning a sale that does not include the original construction of the home) we struggle to find comparable sales. I have found, however, that when my appraiser knew that the reason for this lack of homes was that they are super desirable, not that they were unmarketable, my appraised value went UP.
Another approach with finding a comparable sale is to recognize that many, if not all, of the bale homes will not be listed in the MLS (multiple Listing Service) as straw bale homes. Think about it, how many times have you looked to buy a home off the MLS as a fiberglass insulation house? Probably never. Bale homes are homes first and bales second. Finding a listing that specifies straw bale may not be possible. One avenue that might be productive is looking at “alternative homes.” Sometimes homes may be listed as such. This may include SIPs homes, rammed earth, log homes, and others, but they can often be used as comparable sales because they are “different” just like straw bale homes. Use whatever you can find to get the values the appraiser needs. The fact is, a bale home will ultimately have a better value than a conventional home in the long run. They are more efficient, sound proof and fire proof. All of these details will become more and more desirable as time passes.
Finally, you can look at other straw bale homes built in your area and ask those owners how they got financing. There is a good list, albeit incomplete as not everyone wants to list their home on a public record, at www.GreenBuilder.com. You can look for mortgage companies, home owners, and insurance companies on this site.
As a closing piece, keep in mind that banks don’t finance “fiberglass insulated homes,” so why should they finance a “straw bale home?” Unless you plan to build a load bearing structure, you don’t have to tell anyone in the banking system that you are building with bales. You are building a post and beam home with cellulose insulation. I prefer to tell people that I am building with bales and push the envelope a little in hopes of helping the next person; however, if I am up against a wall and have only 2 or 3 potential banks left on my call list, I will revert to the post and beam style description to ensure I get an approval.
This is one of the coolest and most beautiful straw bale construction concepts I have seen in a long time. Although not something for the owner builder per se, this technique makes the potential for commercial straw bale construction a reality and can even be used in residential applications if the site location and project scale are right.
The overall beauty of the finish product is amazing enough, but couple that with the fact that the building is carbon negative, not carbon neutral, and you have a super insulated, beautiful, and environmentally responsible building. Even the factory that makes the panels is mobile, thus reducing the shipping impacts of the panels once they are manufactured.
All in all, I think this product could have a large impact on the way commercial buildings are built. I certainly hope it does. I strongly recommend that you check out the website for this company at www.modcell.co.uk. There is a cool slide presentation on the overview page that is worth checking out to see how the process works from start to finish.
When building curved walls, some of the most difficult aspects to deal with are those that don’t naturally curve. For example, large windows in a curved wall will create an area where the window either sits inside the plane of the wall or outside that plane. There is no way to bend the window, other than buying expensive curved windows, so you have to get creative in how you finish the window installation. You might add an over sized sill to handle the difference, or hang the whole thing out side the plane of the wall with a creative faux finish. It’s up to you.
One place that can be difficult is in the mudsills, or tow ups as they are often referred to in straw bale construction. As you can see in the photo above, bendable steel channel sills have been created to make the framing of conventional curved walls easy. These sills work great for stick framed homes and I have used them on several houses with great success. The problem for us bale builders is that the steel channel does not provide adequate nailing surface for the attachment of our mesh, nor does it give us any uplift for the bales to get them above the foundation or floor system. We need something else.
One of the easiest methods to handle this situation is to use laminated plywood cut to the radius needed. Because many, if not most, jurisdictions call for pressure treated lumber to be used in contact with the foundation, you will want to get a few sheets of pressure treated plywood for the bottom lamination or two. Each layer should be glued and screwed to the next. The screws are more of a temporary hold than anything as the glue, once dry, will be sufficient to hold the lamination together. Be sure to use strong glue and one that can handle getting wet without losing strength or bond. Gorilla Glue is a good option; however, it can be a little different to work with, so make sure you follow the product instructions.
In the above photo, you can see how a scarf joint is used at the linear connection points of the laminates. This gives a positive glue joint from end to end of the plywood as well as face to face. Be sure to stagger any end joints by at least two feet.
By creating a simple template for the curve, you can use a router or jigsaw to cut many layers in the exact same shape. Once the whole assembly is put together, you can move it to the location in which is is to be installed. Don’t try and do the entire sill in one big circle, using scarf joints all the way around. It will end up driving you crazy. Instead, create manageable lengths that can be laid in place like any other toe up/mudsill system. Use anchor bolts as you would with other systems to hold the mudsills in place.
Several people have written to me asking how to find the welded wire mesh I use on my bale homes. It is hard to find, no doubt, but it can be found, I promise. Unfortunately, I don’t have a long list of suppliers. All I have is my West coast supplier. If you have successfully found the material in your part of the world, please let us know where and save the rest of the SB folks out there some time and sweat!
Here’s the name of the company who supplies my mesh. They will drop ship directly to your location which helps in the shipping costs; however, get all that you need at once because the shipping is not cheap and one big delivery will cost you less than two smaller ones.
Flynn & Enslow Inc
1530 17th St
San Francisco, CA 94107
Here’s a great article about the effectiveness of straw bale walls in earthquakes. This study shows how strong they really are by subjecting the 14’x14′ straw bale house to 200 percent more shaking than was seen in the Northridge, CA earthquake of 1994 which holds the largest measured ground acceleration in the world. You can view the article here: http://www.sciencedaily.com/releases/2009/04/090403104229.htm or read it below.
Straw Bale House Survives Violent Shaking At Earthquake Lab
ScienceDaily (Apr. 5, 2009) It huffed and puffed, but the 82-ton-force, earthquake-simulation shake table could not knock down the straw house designed and built by University of Nevada, Reno alumna and civil engineer Darcey Donovan.
The full-scale, 14-by-14-foot straw house, complete with gravel foundation and clay plaster walls, the way she builds them in Pakistan, was subjected to 200 percent more acceleration/shaking than was recorded at the 1994 Northridge, Calif. earthquake, the largest measured ground acceleration in the world. After a series of seven increasingly forceful tests, in the final powerful test the house shook and swayed violently, cracked at the seams and sent out a small cloud of dust and straw … and remained standing.
Donovan oversaw the successful series of seismic tests run March 27 at the University’s world-renowned Large-Scale Structures Laboratory. She was testing her innovative design for straw bale houses she has been building since 2006 throughout the northwest frontier provinces of Pakistan, in the foothills of the Himalayas between Pakistani tribal areas and Kashmir. Her design uses bales as structural and load-bearing components rather than just insulation as in other straw-bale designs.
“We’re very pleased with the results,” said Donovan, founder/CEO of the non-profit Pakistan Straw Bale and Appropriate Building (PAKSBAB) organization. “The house performed exceptionally well and survived 0.82g (0.82 times the acceleration of gravity) and twice the acceleration of the Northridge quake. The Geological Survey of Pakistan estimates the 2005 Kashmir earthquake to have had peak ground accelerations in the range of 0.3 to 0.6g.
Most people were killed and injured in that October 2005 earthquake as they slept when their poorly built houses collapsed on top of them. The magnitude 7.6 earthquake killed 100,000 people and left 3.3 million homeless or living in tents.
“Our goal is to get the largest number of poor people into earthquake-safe homes. We want to make it as affordable as possible so they build a safe home. We want to save lives.”
“Straw bale houses are used around the world, but those have posts and beams for support and rely on energy-intensive materials, skilled labor and complex machinery, making it unaffordable for the poor,” Donovan said. “In our design, the straw bales are the support, and not just for insulation. Our design is half the cost of conventional earthquake-safe construction in Pakistan. The materials we use clay soil, straw and gravel are readily available; and we utilize unskilled labor in the construction.
“We build a small, steel compression box, pack it with straw, which is readily available from the Punjab District, literally stomp on it to compress it, add a little more, stomp on it a little more, and then finally use standard farm-type hand jacks to do the final compressing of the bales,” Donovan said.
The site-fabricated bales are not as wide as those used in a typical straw bale building, and the fishing-net reinforcement and gravel-bag foundation are nonconventional.
“We fill old vegetable sacks with gravel, like sandbags, for the foundation. The bags are fully encased, or boxed, in a mortar made from clay soil and cement. It’s as low-tech as possible using indigenous, affordable materials,” she said. The earthquake-safe buildings are 80 percent more energy efficient than modern conventional buildings at 50 percent of the cost. Her group also trains local residents how to build the homes.
“Our system is different than anything ever tested,” she said. “We’re doing seismic research on the house to have data to show its structural integrity.” While there are no building codes in the region, Donovan and the organization she founded, PAKSBAB, are pursuing an endorsement from Pakistan’s newly formed Earthquake Reconstruction and Rehabilitation Authority.
Scientists will analyze the seismic-testing results, and Donovan will write a detailed report and seismic design and construction recommendations to be published in the Earthquake Engineering Research Institute’s World Housing Encyclopedia.
Donovan has been a practicing engineer since 1986. She has a bachelor of science degree in mechanical engineering from Stanford University, a master of science in civil engineering from the University of Nevada, Reno, and is a licensed Professional Civil Engineer.
The research was conducted at the Network for Earthquake Engineering Simulation Consortium, Inc. (NEES) shake-table site at the University of Nevada, Reno as a NEES Management, Operations and Maintenance award shared-use project.
“I am extremely grateful to EERI, NEES and UNR for their generous support, and to all the hardworking volunteers who dedicated countless hours to this project, Donovan said.
The non-profit PAKSBAB relies on donations and grants to continue its work. For more project information, visit http://www.paksbab.org.
Adapted from materials provided by University of Nevada, Reno, via EurekAlert!, a service of AAAS.
I received the following email a few days ago. It is a really sad story about how insurance companies can take us all for a ride, straw bale or no straw bale. The owners of the nearly complete straw bale home need an attorney’s help to battle their insurance company who is refusing to pay out for damages after a non straw bale related fire destroyed their home. There are important lessons to be learned in this sad story. Please read on and if you are an attorney who wants to help, please let us know by commenting on this post. I will put you in touch with the owners. Thanks in advance
Hi Andrew – At the end of February, our 80% complete straw bale/steel frame home burned to the ground. There was a propane tank leak, and it didn’t take long for the air to catch fire. Of course most people would like to blame the straw; however, there is little evidence of this being the problem. After the fire, there was tons and tons of piles of straw that did not burn. In fact, right next to where a very thick steel I-Beam twisted under the heat of the fire, lay clean bales with just one scorched side. I was quite surprised how well the straw held up to the heat, while the OSB SIP panel roof and the wood floor trusses completely disappeared.
I am writing to tell you that our insurance company is being very ruthless. Having found no blame on our part, nor the straw … and calling it a combustible accident … the only thing they can cling to is giving us a percentage of our policy … NOT the dollar amount of our loss. As this will force us to go bankrupt and not be able to rebuild unless we can get our full policy, I thought it couldn’t hurt to reach out to the straw bale community in hopes there is an attorney among us that would be willing to fight on our behalf for little compensation.
What is most profound to me after all this tragedy is remembering all the “fire” jokes about straw for years when I would tell people about my dream. So the first thing that happened when people found out about the fire was was that they felt their fears were vindicated. But when they see the photos, and see sooo much straw left and not but a couple scraps of wood …. it’s definitely something to make you stop and think.
In a way… the fire confirms to me that straw is a very safe product if the site is kept clean, and there aren’t any combustibles like propane tanks and wood!
I have a photo that shows how far away from the house the fire burned. It actually caught our conversion van on fire but the straw wall between the house and the van got only slightly scorched. It’s the only wall the firefighters didn’t use the back-hoe to tear apart bales because by that time they figured out that breaking the bales apart was spreading the fire, not stopping it. Had they known to keep the bales together, the fire would have gone out sooner. You can see all the photos of the damage at http://s211.photobucket.com/albums/bb71/CadillacMeaghan/2009-02-28%20Fire/.
We had just gotten half the slab heated with the in-floor, and were using a propane salamander to help get the rest of the house warm so we could plaster the following week. The fire never would have happened if we had been able to get to plastering.
I hope this won’t happen to other people. It started way back in July when we wanted to order our SIP roof panels, but the bank wouldn’t pay for them until they were on site, and the SIP supplier wouldn’t ship them unless they were paid for. So we were at a stand still until the lumber yard agreed to buy them for us on NET30. I shed a lot of tears back then, knowing what that was doing to my timeline. The Roof did not show up till the first week of November, and the panels were installed during the first snow storm. That is why there was no plaster on the bales. That would have stopped the fire after it had consumed all the propane in the air. Unfortunately, you can’t plaster when it’s freezing. Of course, the bank wasn’t so concerned then, but they are now! A small delay in the timeline proved to be the thread that burn downed the house.
Amazingly, the fire department not once blamed the straw and in fact said it made their job harder to put the fire out because the bales didn’t want to burn fast enough.
Thanks for any advice you could give us.
What is the perfect bale to use in a straw bale house? I am asked this question a lot. Most times, the question refers to what type of straw is the best. Some people say rice, others say wheat. I always tell people to buy what is most local as long as it is dense, dry, and clean. The other side of this question is in relation to the size of the bales to be used. Many people want to know if a 2 string bale is better than a 3 string bale for home construction.
Once again, I believe the best bales are those most local to your construction site. In general, most farmers are moving towards bigger bales and so that will have an impact on what you can find in your area. Three string bales stack more easily in the field and are more stable when moved by a squeeze (farm machine that moves large blocks of bales). For that reason, more 3 string bales are available today than 2 string, in most markets. So, first concept: buy local.
Here’s the advantage for two string bales: they are easier to work with. They are lighter, smaller, and generally easier to work with than 3 string bales. I prefer two string because I can handle the bales by myself whereas three string bales take two people to move and stack, especially after a long day of baling. The R-value on a 2 string bale is less than a 3 string bale; however, it is already so high, that the difference is not that noticeable. Unless you live in a VERY harsh climate (either hot or cold) the difference between 2 and 3 string bales will be hard to notice.
The advantage of 3 string bales is that they are more solid when stacked. As mentioned above in the field stacking ability of 3 string bales, they are very sturdy because of their larger base surface area. This translates into strong walls as well. I prefer 3 String bales when building load bearing for just this reason. In addition, because they are wider, you can cut deeper niche into them which is also a nice feature.
The reality is that both 2 string and 3 string bales have their advantages. See what is available to you locally and then decide which advantages best lines up with your plans to build. You may find that it really doesn’t matter to you which size you use. In which case, stick with the local kind.
This is really cool. William McDonough is shown in the small video below describing the design for a true eco city in China. Although he has a pretty flat and dry delivery, the 3:20 second video is worth watching. There is so much that can be done in development if we are only willing to think outside the box. The before and after photo of the proposed city site is amazing and absolutely gives me hope for what is possible.
Check out the video here and see what I mean. Consider some of the topics as possibilities for your own home, obviously on a smaller scale. There is much to consider here.