Archive for the ‘FAQs’ Category

Repairing Water Damaged Straw Bale Walls

Drying WallsRepairing water damage in straw bale walls is a skill that is not required very often, especially in well built homes; however, even with the best construction practices, water damage can happen. If it does, it’s important to know how to recognize it and how to fix it. Below is a series of steps to consider wen dealing with water damaged walls.


Debunking the Rodent Myth

I know, I know…For most of you this is old information, BUT if there are any folks out there that still have a worry in their minds (and it’s OK if you do!) about straw bale houses and rodent invasions, this latest “Straw Bale Minute” is a must watch. Trust me, rodents would much prefer to set up residence in your neighbor’s conventionally built house with lovely pink insulation than live in straw bale walls. You can hear why in this “Minute” below:



Conversations on a Plane

United AirlinesGabriella and I have noticed a recent surge in new subscribers to and many who have signed up have contacted us to let us know they are brand new to the world of straw bale construction. We want to welcome all of you here and we figured it would be helpful to give you an introduction to what it’s like to build a straw bale home. It occurred to me that one place I tend to enter into conversation about straw bale houses with folks who have never heard of them before is when I fly somewhere to teach a workshop. Once the person in the seat next to me gets me going it’s hard to shut me up! “So what do you do?” is generally all it takes to trigger a familiar dialogue.

“Wait, you teach people how to build houses out of what? Straw bales? You need to say more about that.” And so it goes…


Ten Tough Questions Answered

I recently asked a bunch of you to send me your toughest straw bale question. I had about 200 people answer the call and I thank you for writing in. Below are the answers to the top ten of those questions. Some of these questions are compilations from many questions as some of you asked similar questions that were best answered in one shot. I hope you enjoy the question and answer session!

Q: Is straw bale construction limited to right angles or can more organic shapes be utilized? It seems that nature points towards organic shapes like curves, rounded edges, and soft lines yet most of the homes I see are built to conform to squares or rectangles.

A: It’s true that nature suggests more organic shapes in the way it builds. Paul Simon says it best in my mind: “Nature gives us shapeless shapes of clouds and waves and flames. But human expectation is that love remains the same.” To me, this sums up how we as humans tend to change things to fit our needs as opposed to allowing our needs to be met by what exists around us.

The answer is in short yes, bale structures can be built in organic shapes. In fact, they do a really god job of building organic shapes because they can be molded, reshaped, bent, and fitted to almost any design. The difficulty comes with the rest of the structure. For example, if you have a curved wall that has six windows in it, how do you deal with the curve of the wall and the flat of the glass? How about the roof structure? Roofs are hard enough to build when the structure beneath them is a rectangle, but if you start throwing organic shapes into the mix, they get even harder.

So it often becomes about the bottom lines: cost and level of difficulty. It seems that the human race of today’s modern culture (generally speaking) is looking for the least expensive way to do things with the least amount of effort. Some call it frugal, others call it lazy. Whatever you call it, the trend seems to be toward creating simple houses that border on downright boring.

I say, build organic! Stretch the limits of what your neighbors think is possible. Here’s the caveat though: build it well. The other side of the boring house syndrome coin is the folks that build really cool looking stuff that falls down in a year or ten because it was not built right. That only hurts our chances of breaking away from the square trap. There are some folks out there who are building amazing organic structures to excellent standards of quality and I applaud them for it. I hope more of you join that team!

Q: What about different building details like parapet roofs, inset windows or even flat roofs? I like the Southwest style architecture and would like to utilize that in my design. I also like the idea of having a deck over my living space, thus the flat roof, that my wife and I can enjoy for evening sunsets.

A: Flat roofs, parapet roofs, and inset windows are all interesting design features and ones that I recommend against using. Let’s start with the roofs. Parapet roofs are similar to flat roofs, but are not actually flat. They have a slight slope to them behind the parapet wall, and they drain towards the exterior perimeter. The risk here is that all of the water that collects on the roof structure ends up draining out of scuppers (roof drains) in specific locations. The water runs towards the perpendicular intersection of the parapet wall and roof and then runs along that joint to the closest scupper. Can you picture the potential for risk here?

Let’s imagine that the nearest scupper has a bird’s nest in it or is otherwise clogged. Where does the water go now? It will continue down the intersection until it finds the easiest way out. That could be the next scupper down the line or it could be a nail hole in the flashing detail. It could potentially drain straight down into the bale wall, and without you knowing it for a long time.  Since bales are like giant sponges, they will soak up as much water as they can get until they reach saturation, at which point, you may discover you have a leak. Of course, at this time, it’s too late.

Flat roofs have the same issues of potential leakage; however, they generally don’t have the wall/roof intersection on all sides. Sometimes they don’t have it at all. The biggest issue here is the potential for standing water to find its way in through the waterproof membrane as described above. A single nail hole could do the trick.

Another issue with both flat and parapet roofs is that there is usually no overhang to protect the walls from driving rain. This means that your only line of defense against the forces of nature is the plaster. That’s not enough. Lime plaster, my personal favorite, has a relatively high capillary action and so will actually absorb moisture. This is a good thing as it helps to draw moisture out of the bales; however, if under constant barrage by the weather, the amount of moisture in the lime may soon be too much for it to handle and the bales may start to draw moisture from it instead.

Inset windows can be done with more confidence than the flat or parapet roofs, in my opinion. Special adhesive flashing details need to be used for this to work well. Remember, you’re relying on your flashing 100%. If it fails, the window plane is directly above the top, FLAT surface of the bales. A leak here will drain into the top of the bales and that’s a hard leak to discover until it’s too late. I believe I already have the cross sectional diagram for how to flash this style window on the site. If not, let me know and I’ll post it. (I would check but I’m currently in the car driving to my son’s hockey tournament and have no internet access here!)

Q: I want to build my house in a humid climate. Is this a problem? If it’s possible, what changes do I need to make to my design to accommodate the humidity and wet climate in general?

A: Humidity is certainly more of an issue than rain. That’s because rain can be completely designed out of the equation. A wrap around roof or other structural design element can keep rain completely off of your walls; however, humidity finds its way into every inch of your structure no matter how big the roof.

In recent months, I spoke with a number of people who live in bale homes in the Southeast and they reported back that the humidity there has not been an issue for them. I taught a seven day workshop in Tennessee in July of 2010 and was shocked to see how well the bales did in the highly humid climate. Each morning, mid day and evening, I would measure the moisture content of the bales with my bale meter and I was amazed to see how consistent the readings were, always below 15%.

As much as bales have the ability to absorb and release moisture, they can always use a little help, especially in highly humid climates. The inclusion of a Heat Recovery Ventilator (HRV) is a great idea. This machine will constantly circulate fresh air into the house without losing the conditioned properties of the air it expels to the outside. In that process, it pulls excess humidity out of the air and drops it outside the home via a condensation line. This is a great help.

Other design elements to consider are placing the house properly on the site so that you can take advantage of prevailing winds, which can help to dry out the house. Equally important is the design of the house to receive the drying effects of the sun. The more passive design elements you can include to help you handle the added moisture in the air, the better. The use of the HRV should be considered a back up to the passive elements, in my opinion, since you never know when the lights might go out for a stretch of time. If you’re too dependent on the mechanics of your house, you might be in trouble during an extended power outage.

Q: If straw bale construction is so great, then why aren’t more people doing it?

A: This question really caught my eye. Sometimes I find it hard to believe that more people haven’t jumped on the straw bale train too. We all know the benefits of building with bales: super efficiency, sound proof out the wazoo, beautiful, environmentally sound use of materials, fire resistance, and on and on, yet, they’re still not very common in most communities. So why is that?

I think there are a number of reasons that play into this. The first and biggest is that the general public does not like change. The masses move slowly. This has been true throughout history and is no different today. If someone told you that the best thing in the world to build a house out of was used sweat socks, would you believe them? How about if you heard that from 10 people, 100 people? Eventually, you might start listening, but it would take a while for you to jump in, I imagine. It’s the same with straw bale construction. For those of us who know about it and understand it, it’s simple, but for those who are just hearing about it, it may sound crazy.

That leads me to my next point: not enough word of mouth in the larger circles of the world. For too long straw bale construction has been the secret child of a select few. I’ve heard many people within the straw bale community say that straw bale will never catch on within the main stream. There are two problems with this statement. The first is that it is self-defeating. If I don’t believe that something can happen, then how can I move towards helping it happen? In my mind, I can’t.

The second “problem” is that of “the straw bale community.” If we knit ourselves into a comfortable, yet tight ball of yarn then we can’t reach out to those on the outside. The fact of the matter is that it’s the folks on the outside of that circle that most need to hear about what we’re doing. Otherwise, we’re just shaking each other’s hands and smiling at those who already agree with us. I want us to reach further. It will be uncomfortable and it will probably stir some waters and make some people unhappy, but in my opinion, this is not about a small group of us happy. It’s about providing the world with sound, environmentally responsible building practices.

Q: How do you find restraint from strangling the endless parade of people who ask: What about fire and mice and the pig thing?

A: This was too funny not to include and it fits into the last question pretty well. To me, this is about education, once again. I have answered those questions so many times, you can hardly imagine. I always answer them with a smile on my face because I realize that each person I answer the question for is one more person who may be able to see the value of straw bale construction. Some of them are trying to show me that I’m crazy. That’s okay, I know how amazing this stuff is so I don’t worry about them convincing me of that.

If straw bale construction were seen more prominently in the mainstream media, most of those silly questions would go away. I figure that the existence of those questions is a good gauge for how well “we’re” doing at spreading the word to the larger public. The less I hear that question, the better we’re doing. Each time I hear them, I can see where we need to be more vocal, more in the public eye.

Q: Can I use straw bale to retrofit my old house? I don’t want to knock my old house down just to build a new one. I’d like to use some of the existing structure to my advantage.

A: This can certainly be done. There are some things you’ll need to consider when retrofitting an existing house.

1.     Is the existing house design such that you can stack the bales on the inside of the existing frame? This would allow you to salvage most of the framing, plumbing, and some of the electrical. It would also minimize the amount of additional work you’ll need to perform to accommodate for the bales.

2.     If you have to stack the bales outside of the existing frame, can you easily build a new foundation to support the bales and a roof to cover them?

3.     Will you need to move windows or doors from their current location? Wall openings should be flush to the outside, in my opinion, so if you have to extend the bales to the outside of the existing frame, then you’ll have to move your windows and doors to the outside of the new wall plane created by the bales.

4.     Will you keep your original siding or replace it? If you replace it, what will you use? The type of siding will affect the way you stack your bales to some extent. For example, bales stacked tight to the interior face of the original framing (avoiding notching) would not provide adequate support for plaster so you would have to provide some other way of siding the structure.

As you can see, there are a lot of details to consider and each project will be different. The key is that it is possible and in many cases is a good idea. Some houses will be better knocked down as the amount of work they take to use in retrofit will be more than the value you get from saving them. In these cases, consider donating your house to the local police and fire departments for training. I don’t mean give them your house. I mean let them use the house.

I did this a number of years ago and it was a blast. My friends and I got to role-play against the SWAT team while they trained on hostage situations. We were the bad guys! After we were done, I had the fire department come in and use the house for a week of on-site training that culminated in a “burn to learn” training of actually burning the house to the ground. I should say that before either of these departments came in, I allowed the local building material salvage guys in to take what they wanted. That way, anything worth reusing was pulled from the house before it went up in pepper spray and then smoke!

Q: How do I find a lender that will work with me on my straw bale structure?

A: This has gotten a lot harder in recent years because of the financial downturn. I place a lot of the blame for the downturn on the lending industry to begin with for making loans on projects that should never have received financing, so to hear that industry tell us that our projects are too risky is very frustrating. That said, that is often the words we’re given by lenders. This is, once again, a question of education.

Perhaps you can find a lender willing to receive an education from you about the merits of straw bale construction. Most likely not, but I always suggest you try. If you have say 5 lenders in your area that you might be able to work with, tell a few of them exactly what you plan to do and why they would be smart to lend to you. Let them understand that this is a growing industry and they would be smart to take the lead in the field. Be known as the “go-to” company. Speak to their bottom line and you’ll likely have more luck than if you try to talk to their lender brain. No offense to lenders, but in general, they are charged with protecting the company’s bottom line and so anything outside of the very small box they are handed is often tossed out without a second glance.

There are “green lenders” out there and they are obviously a good place to look as well. They may have higher points or other costs, but they are pushing a slow to change industry, so the extra cost is simply the price we pay for their willingness to “take a risk.” If you don’t find anyone to lend to you after you’re about half way through your list, start asking for a loan on a post and beam structure with cellulose insulation and leave out the words “straw” and “bale.” After all, nobody gets a loan on a fiberglass insulation house right? Why should you highlight the insulation (assuming post and beam here of course). Just be sure to check for any policy exclusions that could come back to harm you later.

I really encourage you to approach at least a few lenders with the words Straw Bale written proudly on the page. The more they see that, the more likely they are to start lending. Again, they see a trend that could be a niche market and a smart marketing director will jump on it.

Q: I plan on adding a straw bale addition to my house. What considerations do I need to make for this to work?

A: A straw bale addition is not very different from a conventional addition. The biggest difference is the point of attachment of the new to the old. You need to make sure that you have a solid attachment and that the connection is really well flashed to eliminate any risk of water infiltration. Other than that, it’s no big deal.

Q: How do I know if my city will allow straw bale structures to be built? Further, how do I find straw bales? Even further, is there a data base of regions, states, or even countries that produce straw bales?

A: Some of you just couldn’t help but ask more than one question! I would probably be the same.  Anyway, let’s start at the beginning. The best way to find out if bale structures are “allowed” in your city is to ask. The worst thing that can happen is they can say no. If they do say no, be sure to ask under what section of the code are they making that decision. The fact of the matter is that bale structures tend to either meet or exceed almost ever detail of the code if designed and built properly.

Once you know why they are saying no, you can have a clear, factual discussion with the building department and you can provide them with data sheets that support your position. In most cases, an answer of no is more an answer of “I don’t know.” Once again, education is key. Here’s the detail that often gets missed: When educating building officials, do so with respect. All too often people jump on the defensive with inspectors and want to hate them before they walk in the door. This will not serve you well, ever. Help them understand the truth behind the myths they may have heard. Invite them to learn a new technology that is gaining prominence around the globe.

Finding straw is best done by going to the source. Talk to farmers. Go to farm supply stores. Look in farming supply magazines. If you don’t have any of those avenues, widen your search a bit. Chances are there is an agricultural areas within 500 miles of you. That’s a long way to go, I know, but do you think the plywood your neighbor’s house is built of came from a more local source? Probably not.

I wish there was a more accurate database of bale sources. Unfortunately, that is something that has not been successfully created to the best of my knowledge. If I’m wrong, and I HOPE I AM, please correct me here so we can all learn about a great resource we all need. Finally, you can always make your own bales. If you have the crops, al you need is a hand baler (like the old days) or a tractor and baling machine and the time to run it. I baled the straw myself for one of the first structures I built. Were they the best bales I’ve ever used? No, but they worked! Food for thought!

Q: What are the most important aspects of straw bale design to consider when wild fire is an issue?

A: The fact of the matter is that the bale aspects are not the biggest area of concern, the wood frame ones are. Here are the most common details to consider in regards to wild fire:

1.     Gutters filled with debris. Over the course of a year leaves, pine needles and other debris may collect in the gutters of your home.  This isn’t a problem in the wet months (other than potentially clogging your drains, but that doesn’t relate to our topic here), but it can be disastrous in the dry months. A single burning ember flying in on the heat winds of the fire can set your whole house alight if it lands in a pile of dry debris right below your roof line. Keep your gutters clean.

2.     Foundation vents are another place of danger. Very often debris will collect in the vents during the year. If an ember catches the debris on fire, the fire born winds will quickly push the flames into your crawlspace and light your floor beams on fire. From there, I don’t care what your walls are made of, they have no chance.

3.     Decks can collect the same debris and light it up the same way. A bunch of leave bundled under the deck can quickly burst into flames if embers are blown under the structure. The deck then lights up and off goes the house.

4.     Fuel sources around the home like ladder fuels are notorious for setting homes on fire. Be sure to limb up your trees, remove shrubs from underneath them, and keep any grasses mowed and maintained.

Like I said earlier, most home fires are not the result of the straw in your walls, but the conditions around your home. Finally, be sure to protect your bale walls well from fire until they are plastered. The straw itself is not so much at risk, but the chaff hanging off the bales can flare if contacted by flames. If it does, it will chase up the wall and catch the roof framing on fire, which will then collapse into the house. Chance are, your bale walls will be fine in the end, but the house will be heavily damaged in the process.

Recent Radio Show

I was recently invited to be a guest on the Jefferson Exchange, a popular morning talk show here in Oregon and California to discuss straw bale construction. The program is an hour long and covers many aspects of building with bales.

The first fifteen minutes or so is primarily a conversation between me and the host. The remainder of the show is in a question and answer format whereby I answer caller’s questions. I hope you enjoy the audio podcast. I had fun making it.

img_1757.JPGTo listen to this podcast on your computer please click the play button at the bottom of this post. Right click the following to download the podcast to your hard drive:
My Straw Bale Radio Interview: January 2008

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To listen to this interview now please click the play button below

Mold Spores in Straw Bale Homes

I recently heard that some, if not all, straw and hay out of the Pacific Northwest has a mold spore in it. The question that accompanied this information is how to counter act the affects of the mold on the bales so they can be used for constriction.

The answer is quite simple: keep the bales dry. Mold can only grow and therefore have an affect on the bales when there is moisture. As long as the bales are kept dry, the spores will not be able to grow and will eventually shrivel up. The walls, sealed with plaster, will not allow any of the spores to enter the habitable space.

A Quick Word on Wall Height

I get a lot of questions about what height a bale building can be. People want to know if they can build three story homes with straw bales or if they are limited to one story. That all depends on the way you chose to build: load bearing or in-fill. There are differing opinions on how tall a load bearing structure can be however, and some newer applications are pushing the envelope to its limit. A safe assumption, especially if you plan to get code approval and do not have specific engineering to show otherwise, is that the load bearing structure will be limited in height as compared to a post and beam structure.

You can build tall structures (three stories, etc) with straw bales if that building is a post and beam structure or otherwise structurally framed with something other than bales. The bales would be used as in fill. The frame handles the load and the bales offer the insulation and “feel.” This is a great way to build more complex designs as well because there are more options available to you with the inclusion of a structural frame

If you want to build load bearing walls (no structural framing other than the bales themselves), you can only go single story, plus a loft, if designed properly. The height of the wall is limited to a height vs. wall thickness ratio. The thicker your bales, the taller you can go. After a three string bale, adding additional thickness to increase height becomes a waste of materials and space in 99.9% of the cases. Load bearing straw bale homes are more simple in design as a result and are often easier to build. As always, identifying what is most important to you before you start building is key. Make sure you are focusing on the most important aspects of the job during design, and you will end up with what you want in the end whether it be simple and load bearing or complex and structurally framed.

Can a Bale House Survive Without a Heat Source?


I have a farm in Trinidad, Colorado (although I live in Denver) and on it is an old house that I want to tear down. I would like to build a house that is so energy efficient that I can leave it with no heat in the winter and have no problems with freezing, etc. In other words, I want to create a cave-like environment where the temperature stays roughly the same as outdoors in any weather. Can a straw bale house achieve this goal? I have double pane, low e-glass windows in my farm house
now and would transfer them to the new house. Please let me know if this is possible with the straw bale construction.
Thank you.

The biggest aspect of this working is the design of the house. You will need to incorporate enough passive solar design to create a natural heat source for the home. Without any heat, the house will eventually equal the temperature outside, even if that is 0 degrees. If the house has passive solar design, it can generate its own heat by using the sun to warm interior floors and other heat sinks. That heat is then slowly released into the home and the4 bales insulate to such a high efficiency that they can contain that heat through the night. It is possible, and it will take some detailed planning and execution. Good luck.


The Latest “Building Green” podcast

Welcome to the “Building Green” podcast. This is my monthly Q&A session where I answer your green building and straw bale construction questions.
This month I answer the following questions:

1. Any thoughts on how to go about looking for land that is suitable for straw bale building?
2. Metal roof or composition? Or other? Which is the best environmentally speaking?
3. Must you have an architect/engineer that is experienced with bale construction approve your plans to ensure that the building codes are fulfilled?
4. How do you go about finding a structural engineer who is versed in straw bale?
5. Our interior plaster walls are very rough and sandy. Is it possible to paint the interior walls? If so what would you recommend?

To listen to this podcast on your computer please click the play button at the bottom of this post. Right click the following to download the podcast to your hard drive:
Building Green Podcast: April 2007 Edition

Would you like to be alerted whenever a new audio or video podcast is added to this blog? If so click here to subscribe to our Building Green Podcast Feed.

To listen to this podcast please press the play button below

The March 2007 Question and Answer Podcast

Welcome to the March 2007 “Building Green” podcast. This is my monthly Q&A session where I answer your green building and straw bale construction questions. Sorry it has been so long since I uploaded a Q & A podcast. I have been super busy putting together a brand new Load Bearing production and writing a straw bale construction field manual. This month I answer the following questions:

1. Are you limited to just stucco on the outside and plaster on the inside for a straw bale house, or can you use wood siding or brick on the outside and inside? Is there a system to attach wood siding to the bales rather than plaster?
2. Can you use shotcrete or stucco blowers on the walls instead of hand trowelled plaster?
3. What’s your advice on finding local lenders who can help with straw bale?
4. Do straw bale houses have to be rectangular? How about an octagon?

To listen to this podcast on your computer please click the following link or right click to download the podcast to your hard drive:
Building Green Podcast: March 2007 Edition

Would you like to be alerted whenever a new audio or video podcast is added to this blog? If so click here to subscribe to our Building Green Podcast Feed.

Please click the play button below to listen to this podcast!

Straw Bale in the 4th Grade Classroom

I received an email today from a curriculum writer for a fourth grade class in Kansas. The idea is to write a curriculum that introduces the class to straw bale construction as an economic and environmental asset. I have attached the email below because I think it is so cool that fourth graders will be exposed to this! She also asked a series of questions which I have attached with the email along with my answers to them.


I am developing a unit on shelter for 4th grade students in Kansas. I need some information on straw bale building and don’t want to create errors as a result of my lack of knowledge. I am hoping you have time to respond to a few questions. A very brief background history: The purpose of my unit is to teach archeology so that students will have a passion for protecting archaeological resources. My first priority in design is to make sure my unit meets state curriculum standards. I found my entry point through the economics standards.

So, in short, students will examine the archeology of the Wichita grass house and the archeology of the African American dugout, look at the use of natural materials to build energy efficient houses and then bring that knowledge forward in to the present, and examine houses we could build today using local resources.

Students will use their economic standards to create a business that promotes energy efficient homes. I thought since Kansas is an agriculture state, that access to affordable and abundant straw would allow students to think about promoting straw bale houses. The enduring understanding that I want students to have at the end of this is: Building shelters using local resources protects the environment and saves money. Here are my questions so far:

1. Does building with straw bale protect the environment? Why or why not?

Answer: It does for several reasons. Straw is a waste product of the grain trade and as such is disposed of annually. In the U.S. alone, we burn over 200 million tons of straw each year. The particulate matter and Carbon Dioxide released into the environment is very unhealthy. By using the straw instead of burning it, we improve air quality. Secondly, once installed in the home, they provide excellent insulation, reducing the home owner’s reliance on mechanical cooling and heating. The energy saved directly translates into environmental impact.

2. What other ways does a straw bale save money besides being able to build yourself and the energy savings?

Answer: If you are building yourself and using a load bearing assembly, there are no lumber costs for the walls except for the window and door bucks. If building a post and beam, then the savings are mostly in the efficiency of the home.

3. Is it reasonable to think that a farmer could make money raising straw for homes?

Answer: Absolutely. Like I said earlier, many farmers simply burn the straw to get rid of it. If they baled it and sold it for $4 per bale or so (based on market conditions) they would be turning a profit for their waste product. Consider that the burning of a field still takes fuel and labor. The added fuel to run the equipment would be offset by the profit of the bales.

4. Do you know of other alternative kinds of building materials that could be used locally in Kansas (I realize you are from Oregon and might not be able to answer this)?

Answer: Cob (mixed clay, sand and straw) is an alternative building material although it is very labor intensive and is not covered in the building codes like straw bale is. Rammed Earth, also labor intensive and not covered, is another option still used. One can build a house out of almost anything: tires, old magazines, etc. I am not sure I would endorse that though.

5. Do you know any straw bale builders in Kansas?

Answer: I do not. You might contact Sven Erik Alstrom. He is an architect who works with straw bale and will likely know of local builders. His number is 785.749.1018 (