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Articles on Straw Bale Construction

Being probably the most querried topic within natural building on the internet, straw bale construction has become what some people refer to as a ladder or bridge technology.  It is an easy path for people to follow and understand who are new to such a vast and under-utilized family of construction techniques and systems in this modern age.

The Last Straw was founded as a response to the need to disseminate information primarily about bale construction, but soon broadened its scope to include the entire natural building world and beyond.  You will find a wide range of topics on this page related to straw bale construction and probably more related systems to explore.  Ask questions in the comments section of each article and browse multiple pages to find what your seeking.

 

Straw-bale Sound Isolation and Acoustics – TLS #53

By Building Science, Design, Sound, Straw Bale Construction, Technical, Walls One Comment

This article appeared in TLS #53.  The topic of this issue is Moisture.  It contains an extensive article about Moisture Basics and Straw-Bale Moisture Basics (by John Straube, edited by Bruce King)  it also includes articles on moisture meter accuracy, moisture sensors, seismic resistance, and plaster testing.

by Rene Dalmeijer – The Netherlands

In June 2003, Jasper van der Linden, a building engineering student at the Eindhoven Technical University, Eindhoven, The Netherlands, tested the sound isolation of an earth-plastered straw-bale wall. Rob Kaptein of RAMStrobouw and I assisted in carrying out the test. The test was executed in a true acoustic test chamber according to ISO 140-3. We were able to execute a consistent test giving a good indication of how well a plastered straw-bale wall retards sound.

Based on the outcome of the test, it is to be expected that a reasonably well-designed and built straw-bale wall without acoustic defects (like protruding post-and-beam members) will perform in the region of 53dB and upwards (55dB with A weighting; “A-weighting” means the impedance is corrected to approximate human hearing sensitivity, which varies depending on frequency). The 2dBA increase in performance when compared to the test is mainly because we used very thin (worst case) plaster thickness in the test sample. Normally earth plaster finishes would be thicker. This puts the performance of a straw-bale wall at more or less the same level as a decoupled brick cavity wall and even exceeding it in the critical low-frequency region.

Most everyone who has been in a straw-bale building has had the sensation that interior sounds somehow seem louder, because interior sounds become more distinct for not being drowned out by background noise coming from the outside. This is a clear indication that straw-bale walls work very well as an acoustic insulator. Normally built structures depend on high mass for good sound insulation. But there is also another way of achieving good sound insulation, which depends on a damped cavity surrounded by two not-sostiff membranes with sufficient mass. A straw-bale wall, specifically with earth/clay plasters, is an excellent example of this alternative way of achieving good sound insulation, as the test result clearly illustrates.

The Test

The test was executed in the acoustic lab of the Eindhoven Technical University. The test and test facility is according to ISO 140-3 which is to test the sound isolation of building aperture of two acoustically separated chambers (the test sample is placed in an aperture between the chambers). Although I am aware of the limitations of the test facility for testing a wall system, we have endeavored to make this test as accurate and as representative as possible. The aperture’s size (ISO 140-3 std) is 1.88m2 /20 ft2. The tested straw-bale wall section had the following configuration:

  • Two-string (460mm wide building quality bales laid flat density 120-130kg/m3)
  • Earth/clay straw plaster 25mm and 35mm (intentionally asymmetrical cover)
  • No reinforcing plaster netting or mesh or any form of pinning

table1The chosen sample structure was to be as representative as possible of a normal earth/clay plastered straw-bale wall structure as used by the experienced straw-bale builder Rob Kaptein of RAMstrobouw. Rob was also responsible for manufacturing the test sample. The graph and table summarize the test result.

[Rene’s comment on the measured performance: The result can be expressed as 53dB according to A-weighting. Actually expressing the sound isolation value in one number (i.e., 53BA) is a simplification. In actual fact, giving the performance at each of the various frequencies is much more meaningful.]

Generally this is done at either one octave intervals (1/1oct) or at one-third octave intervals (1/3 oct), the last giving even more detailed information.The graph and table show both measurements (not A-weighted). The dip at around 250Hz is due to the transition between the masws and damped cavity odes of operation of the test sample and should be largely disregarded as part of the vagaries of a test.

The 53dBA test result might seem low but in fact is very good. Most conventional wall systems including a brick cavity wall with much higher mass have a lower performance. Specifically interesting to note is the 2-3dB better performance at very low frequencies of the straw-bale test sample when compared to brick-wall systems. Nearly all wall systems, including stick frame, are able to sufficiently subdue high-and mid-frequency sound, but low-frequency sound is problematic. In practice, better performance at low frequencies is worthwhile because it means that the ever-present background noise in suburban areas is perceptibly reduced.

Recipe for Straw-bale Wall Acoustic Isulation

Besides sheer mass, low stiffness with sufficient mass and acoustic decoupling are very imortant for acoustic sound insulation. The relatively low stiffness of a straw-bale wall with earthen plasters is ideal. The fact that the cavity between the two plaster shells is filled with straw provides excellent acoustic damping. Beware and be careful to fill all cavities and voids with very light straw/clay. Avoid any direct mechanical contacts between the inner and outer plaster shells, as these will seriously degrade sound damping performance. Contrary to what you would expect, loosely packed bales will perform better than very tightly packed bales. Extra thick (>35mm) earth plaster specifically improves low-frequency performance. Cement and lime plasters perform almost as well but earth plaster with lots of straw is the best due to a lower modulas of elasticity (stiffness). Applying significantly asymmetrical plaster thicknesses helps to avoid coincident reverberation of the inner and outer plaster layers. The thicker plaster layer should be on the sound source side of the wall. Pay a lot of attention to all openings and edge details; these are the weak points. An air leak of only one sq. mm will seriously degrade performance. Door openings and windows are literally acoustic holes in the wall; these need special detailing and attention to even remotely approach the acoustical (and thermal) performance of the surrounding walls. Even double doors generally show poor performance compared to the wall. The gaskets and seals in the doors should be double or even triple, but even then there is a problem as, over time, the seals will degrade and leaks will occur. The type of door you are aiming for is more like a steel watertight door in a ship than a house door with multiple closing bolts and tightening clamps. (All of this only if acoustical performance is essential.)

table2In conclusion, I would like to emphasize that, due to the nature of a straw-bale wall (an excellent sound barrier), the wall is not the problem; the connections between the

wall and all other elements incorporated or surrounding it are. In other words, it is the same issue as with thermal and moisture performance. I strongly suspect that most sound isolation tests executed on straw-bale walls are measuring the defects of other structural components or mistakes in the test procedure (a non-calibrated sound source, background noise, and such).

Room Acoustics

Here are some simple rules of thumb depending on the type of acoustics you want, e.g., very lively to very well damped. Soft acoustic instruments require a “live” (reflective) room. Loud amplified sound needs a “dead” (absorbtive) room. The single most important parameter is the reverberation time and level. The harder the surfaces, the livelier the sound. A bathroom is lively, hence your strive to sing even if you can’t. The opposite is standing on top of a snow-bound hillock [small hill or mound] – virtually no sound reflects back to your view. The bigger and harder the room, the longer the reverberation time, e.g., a cathedral. Next the relative dimensions: an oblong box (like Concertgebouw Amsterdam) approaches the ideal. Preferably the relative dimensions are approximately 2 to 3 to 5; this ratio will avoid the formation of dominant harmonic resonance and standing waves. The exact ratios needed for a given acoustical requirement depend on the size and acoustic reflectivity. I personally prefer rooms without parallel surfaces, thus avoiding standing waves. I think if you finish a room with earth/clay plaster on straw-bale walls, with wooden flooring and a well-pitched ceiling, you will have quite acceptable acoustics for musical performances. If it’s too lively, you can always add some damping afterward by placing soft furnishings in the room or hanging curtains on the windows. A bigger audience also helps.

Good acoustic isolation is definitely one of good merits of straw-bale walls. It should be seriously considered for purposes where sound isolation is of importance. It would be hard to find a more affordable solution to building sound studios, quiet houses in noisy neighborhoods, or noisy workshops in residential surroundings.

<[email protected]>

Rene Dalmeier has been interested in straw-bale building since 1998. In June 2005, he finally took the plunge and turned his hobby into a profession by becoming a full-time straw-bale builder.

A whisper = 15 dB … Normal conversation = 60 dB. dB: Abbreviation for decibel(s). One tenth of the common logarithm of the ratio of relative powers, equal to 0.1 B (bel).

House of Straw? – Reprint from TLS #57

By Bales, Design, Straw Bale Construction 2 Comments

 

build-our-house-out-of-straw2Build our house out of straw?

by Stephen MacDonald – New Mexico, USA

This article appeared in The Baley Pulpit,TLS#7/Summer 1994.

“May we look upon our Treasures, and the furniture of our Houses, and the Garments in which we array ourselves, and try whether the seeds of war have any nourishment in these possessions, or not.”

– from the Journal of John Woolman an 18th Century Quaker

“Build our house out of straw?” When our neighbor suggested the idea as a solution to our housing problem, both my wife, Nena, and I reacted similarly. “You must be kidding!” Even when he showed us a copy of Fine Homebuilding with an article in it by Gary Strang (1985) on a studio built out of straw bales, we were dubious. It was just too weird (images of rotting hay, mouse hotels, and pig stories readily came to mind). The idea was too simple and straightforward to be believed.

Try as we might, however, we kept returning to the idea of it. It did seem to fit our condition: Using straw bales was 1) low cost…we were near broke, having used the last of our meager savings to buy a small piece of land; 2) a way to stay cool (and warm)…having just moved to southwest New Mexico from Alaska, I was scared to death of the heat; 3) fast and physically easy to build…I just couldn’t face the slow, heavy work of adobe; and 4) ecologically sound…besides being energy efficient, a straw-bale building uses a renewable resource (often viewed as a waste product) that was locally available. Done right, building with straw uses very few trees.

In the end, we decided to go for it. Seven years later, we have no regrets. Just the opposite. We didn’t know it at the time, we were not the only ones interested. Through Strang’s article and newly formed friendships with Susan Mullen, a permaculturist and close neighbor, and an enthusiastic Matts Myhrman in Arizona, we learned of a small but dedicated network of straw-bale aficionados. Nor were any of us particularly innovative. The true trailblazers of straw were the folks from the Sandhills of Nebraska who, out of necessity, started a tradition of building their homes out of native hay and straw beginning back in the late 1800s and continuing up through the early 1940s.

The work of the Nebraska homesteaders remains the key. It took a fact-finding journey to Nebraska in 1989 by Matts and Judy Knox, his wife, to finally convince us that we, like most of those early Nebraskan straw-bale builders, could further simplify our technologies by using straw bales as load-bearing walls without the time and expense of poles or posts. We modern practitioners of straw have come to call it building “Nebraska style.”

It is this style of building that has captivated my imagination and been the thrust of our most recent building endeavors. Much good work needs to be done to revitalize the straw-bale building tradition and get it accepted into common practice. Tackling the building codes is part of that work along with trying (and sharing through The Last Straw) new and innovative techniques. I have no doubt in my mind that sooner, rather than later, this Earth will demand it of us.

 

 

Nena in front of the MacDonald’s straw-bale home.

Nena in front of the MacDonald’s straw-bale home.

Meanwhile, here are some of this straw-bale builder’s rules of thumb.

I. Keep it small. How much space do you really need? Be honest. Be creative with your space. Small is easy to heat and keep cool. It’s easier to keep clean. It takes up fewer of the earth’s resources and takes up less of its space. You finish the job, at a lower cost, so you can devote money and energy to more useful work. If your teenagers need distance, have them build their own outbuilding or addition. They need to learn the skills, anyway.

2. Keep it simple. Control your impulses to make your house a complicated, “artsy” statement. Simple, small and rectangular houses are beautiful when made of straw and other natural materials. Let form follow function. Again, spend all the time and money you saved by being – out in the woods, feeding the poor, or playing with your children.

3. Build it yourself. Trust yourself. You can do it, especially if you build with straw…and especially if you follow rules 1 and 2. Read building books and magazines.

Ask questions of builders. Build it on paper and as a model first. Track the details. Use your common sense. Be creative with your mistakes. Don’t be intimidated by the “experts.”

4. Stay out of debt. Pay as you go. Assemble the parts as you have the money and time.

5. Use local materials. Use more rock and adobe. Use locally milled lumber and poles. Your neighbor needs the work and you need to know firsthand what demands you’re asking of the forests and the fields.

6. Be energy conscious. Build to maximize passive heating/cooling strategies. Superinsulate your ceiling. Stay off the electric power grid if you can. Put up a windmill or use a solar pump. Build a composting toilet. Raise a garden.

7. Make yourself a home. Don’t just build a house, make yourself a home. Learn to be at home. Do no harm.

6 June 2005 Update

It is hard to believe that 18 years have somehow flowed by since Nena and I first built our little house of straw here in rural New Mexico. Two kids fledged, one now married and making his way at the edge of the Adirondacks in New York, the other just back in the United States after months of solo travel through Europe and western Russia.

Our little house continues to do well. We finally added a small greenhouse to the southwest corner of the place, and several years ago built a really first-class outhouse off the shop. I keep meaning to replace the salvaged (and very inefficient) casement windows we have, and one of these days I’m going to get around to finally plastering the outside of my Nebraska-style office/former teenage daughter ‘cabin.’ “Margosh, margosh” as my Mongolian friends would so often say – tomorrow, tomorrow.

Stephen MacDonald lives with wife Nena, son Orien (and co-author with his father of A Straw-Bale Primer), and daughter Aili, in their owner-built houses of straw in Gila, New Mexico. Steve and Nena live their Quaker faith in numerous ways including active participation in The Friends of the Gila River, working to create a cooperative ecosystem-based Gila River Ripiarian Management Plan with all stakeholders. Steve returns to Alaska each summer to continue biology mammology field work in the bush, and touch base with his northern home for over 14 years in the 1970s to early 80s… and stay cool.

“Somehow Nena and I have survived our various mid-life crises, finding new balance as we age and continue along our now 32-year journey together. I am still very much engaged with my work on far northern mammals (now through the Museum of Southwestern Biology), while Nena, having let her nursing license lapse, spends her days here at home.”

[Guest Editor’s Note. Stephen and Nena’s small straw-bale house has been an inspiration to many. It still inspires because it so effectively embodies the basic principles Stephen outlined of what a home should be a nice place to live in.]

Post Editing Note: If this information is valuable to you, there is much, much more in the published, official version of The Last Straw.  Please subscribe at The Last Straw online.

Sill Pan Design Detail – TLS #51

By Bales, Straw Bale Construction, Technical, Walls No Comments

 

Slope pan flashing to outside.

Slope pan flashing to outside.

Included in TLS #49 (Myths and Realities, Spring 2005) was a discussion of ways to deal with moisture at the bottom of windows. David Eisenberg shared a written design detail for a pan under the window to carry water away from rather than down the wall. We wanted to share a drawing of this detail and David kindly provided one for us to share in Tech Tips.

Here’s the portion of the discussion in which David details this design idea.

“Protecting the bales beneath the windows requires that you catch the water under the window and make sure it gets all the way out of the wall. In other words, ideally, you would have a pan of sorts under the window, sloped slightly to the outside, extending a bit beyond each side and with a lip at the back and on each end (so water can’t just run off the ends), and extending out beyond the exterior wall surface, with a drip edge – so that any water that leaks through or runs down the sides of the window ends up in this pan and is shown the exit. You can make these pans out of metal, plastic, ice and water shield, cast this shape into a concrete sill, anything that will keep the water from leaking through it, but the principal thing here is to make sure that the water can’t get into the wall below the window. You can put your window sill material, whatever it is, on top of this pan flashing being careful not to punch unsealed holes when you install the sill. It can take a little thought and ingenuity to do this, but it assures you that, when the windows leak, the water leaves the building.

sill2

Concept of pan flashing turned up at back and sides extending beyond exterior finished wall with drip edge. Extending behind finish or trim at each side of opening.

“That old practice of just putting roofing paper or plastic over the top of the bales and setting your windows on it and then plastering over it just leads the water down inside the plaster to the bales wherever the water protection ends unless it runs continuously down the wall under the window to below the bales (and we don’t recommend doing that).  It just temporarily moved the problem down, didn’t solve it.”

A Bit About Bale Walls

By Bales, Straw Bale Construction, Walls No Comments

Currently in rough draft form, this information is the beginning preparation for an article or perhaps two that will appear in a future issue of The Last Straw journal with the theme “All About Bales.” Your comments and input are welcome.

by Joyce Coppinger, Managing Editor/Publisher, The Last Straw Journal

Wall Structures
The structural methods used for the design and construction of bale walls are generally of two types: loadbearing and non-loadbearing. Stated another way – bales supporting the weight of the roof and any snow or other roof loads, and any post-and-beam or modified post-and-beam structure with the bales used as infill for insulation only.

Timberframe is the post-and-beam structure of choice in most countries. Posts of conventional milled 4×4, 4×6 and 6×6 wood; lodge poles, timber bamboo and other types of materials have been used. Modified post-and-beam structures are wide-ranging and diverse – anything from box columns to ladder-truss wall systems, to the current experiments in and development of SIP or structural insulated wall systems (also called wall panel systems or panelized walls) using bales as the insulation material rather than rigid foam insulation as the material sandwiched between the sheathing on both sides. [See articles in TLS#42 and #55.]

Widths
Bale walls come in many different widths depending on the size of bales you use, how you lay the bales as you stack them, and even the type of material baled and the method used to stack the bales to form the wall.

Widths Using Small Square Bales: Typical widths for bale walls are 16 or 18 inches when the bales are laid flat (strings or wires on the top of the bale). If stacked on edge, the bale width will be 14 inches with the strings or wires on the side of the bale. If the bale is stood on end to fill a framed space, the bale can be either 14, 16 or 18 inches depending on the size of the bale and the direction in which you set the bale.

Size of Bales
Even though a bale may be called “square,” it’s usually rectangular in shape.

The size of a small square bale may vary by region or country depending on the type of baling equipment used or the method of making the bale, e.g., bale press or hand pressed compared to using a mechanical baler. The bale may also vary because of the type of mechanical baler used and how it’s set to produce a bale.

The small and medium size balers used in some regions of the U.S. have a fixed bale chamber that produces a bale that is 14-in.x16-in., 14-in.x18-in. or 16-in.x18-in. The length can be varied to produce bales between 36 inches and 41 to 48 inches. This is the range of length that is required by most automatic bale wagons used to pick up bales in the field in the U.S..

You should also be aware that there are also other sizes of bales used – some are called “jumbo” bales because of their large size. In some places, these large bales might be called 4x4s or 6x6s or 8x8s. Some people define a square bale’s size as small, medium and large. Small bales can be 24in.x24in.x48-in. Or they can be 14-in.x 16 to 18 in.x 36 to 48 in. A medium bale of this type is around 4-ft.x4-ft.x6-ft., and large bales around 6-ft. to 8-ft. square by 8-ft. to 10-ft. long. Weight depends on the type of hay and settings of the baling equipment.

And density (compactness of the baled material) or compression (how much pressure is placed on the bales to “compress” them when they are created or after they are stacked) of the bales might also change the dimensions.

The binding material on the bales is most often wire or poly twine; sisal (natural fiber) isn’t the best to use as it tends to break while the bales are being handled. Some people don’t use wire as they are concerned about moisture might condense on it or be drawn to it; some feel it’s difficult to work with when retying bales, others feel it’s easier. Some don’t like to use the poly twine because of the coating or because they feel it’s not as easy to work with. In most cases ot comes down to personal preference or type of binding available locally.

Placement of Bales
Bales laid flat are usually 16 to 18 inches wide and 14 inches high; they can be 36 to 40 to 48 inches long. Bales stacked on edge are usually 14 inches wide, 16 to 18 inches high, and the same lengths as mentioned for bales laid flat. Bales used to fill in framed spaces – or stacked on end – can be 14, 16 or 18 inches wide depending on how you orient the bale in the space filled.

There has been and continues to be much discussion about the way bales are laid or positioned when stacked. Are bales set on edge or bales laid flat easier to plaster, and what reasons do balers use to explain a preference for one method or the other? Do the bales laid flat have less or ore insulation value – and why?  Do bales set on edge have more tensile strength than bales laid flat?

What to Use and What Not to Use
A bale made with a mechanical baler that chops the straw as the bales are made probably doesn’t produce the best bale for construction – it tends to fall apart or could be harder to work with when cutting and tying.

A bale made from alfalfa will be hard to use – the alfalfa tends to be woody and brittle, the bales are usually not uniform in shape and perhaps even in size to some extent. This may be true of bales made from switchgrass or flax or other “slippery” materials.

Bales made from tumbleweeds are not suitable for bale building – they are very brittle and highly flammable (usually very dry). The same could be said for pine straw bales – the kerosene in the pine needles is flammable and the pine needles are also one of those “slippery” materials mentioned earlier.

The most common materials used for buildable bales are wheat, oats, rye, rice, and hemp. It’s said that the Nebraska prairie pioneers used prairie meadow hay (probably hard to find these days), cattails and wetland reeds (most often baled during droughts). We’ve heard of the use of bales made with timothy grass, Sudan grass, and barley. We’ve been asked about corn stover and soybean stover – but don’t know of anyone who’s ever used this crop residue as a bale building material. If you’ve heard of other materials used for buildable bales, please let TLS know.

Fire in a House With Straw Bale Walls

By Fire, Straw Bale Construction, Walls One Comment

This article is original content and has not yet appeared in the printed version of The Last Straw.

No, this is not the house.  We dont have a picture of a bale house on fire!

No, this is not the house. We don’t have a picture of a bale house on fire!

This story is a reluctant one about a house comprised of both wood-framed and straw bale walls lost to a fire in 2009. The structure was built over a longer period of time than most main-stream homes.  The different phases incorporated the most appropriate materials at the time for the owners. We are excluding specific reference to the owners and the location of the building due to privacy concerns. For this article we will say that the building is in the central U.S. at approximately 8,000 ft elevation and the Owner’s name is Bob. In the end, it really does not matter who owns the home or exactly where it is. What we will focus on is the performance of the bale walls in the fire, the aftermath, and how the owners and insurance company feels about the whole incident.

The building was an un-permitted residence in a rural mountainous area. As mentioned above, some of the walls were wood-framed, others were built with bales. The bale portion of the structure was round, approximately 26′ in diameter, on a foundation that was an 8″x18″ concrete grade-beam supported by concrete pillars, with a yurt-style roof which included a “tension-ring” cable. The bale walls were Nebraska-Style (no posts) and had a 2×6 box-beam for the top plate with plywood on the bottom but not the top. The box-beam was filled with rigid foam insulation. Both the interior and exterior surfaces of the bale walls were covered with cement-based plaster. Two coats were present on the exterior and one coat was completed on the interior. There were relatively small areas not plastered on the interior, but the location of these un-plastered areas were not specified in my conversation with Bob.

The fire was started in the crawl-space of the framed portion of the structure by accident. It quickly spread throughout the framed structure and overtook the occupants who had to flee for their safety.  Bob is a local volunteer firefighter who was overcome with smoke inhalation and had to be taken away for medical care. He was present for a majority of the fire and taken away before it was extinguished. However, he has some interesting comments regarding the bale walls, how they performed and how they were affected by the fire. The family lost everything to the fire and is now picking through the remains.

The fire quickly engulfed all of the wood-framed structure and spread to the floor and then the roof of the round bale structure. The roof of the round structure collapsed inside the bale walls but the bale walls themselves were still standing when the fire department , hampered by by the long driveway and 18″ of fresh snow, arrived on the scene 50 minutes after the fire started.   Due to smoldering straw the fire department felt compelled to knock the bale walls down to access smoldering area within the walls.  Eventually all the bale walls were knocked down and all of the smoldering extinguished. This process took five days after the initial incident.

Bob commented about how fast the areas with no plaster ignited compared to the bale walls covered with plaster. The windows and doors had been framed using standard wood bucks. These, in addition to the wood box-beam, became the main avenues for the fire to spread into the bale walls. It appeared that the fire moved down from the top and in from the window and door bucks. Had these areas been plastered, or concrete bucks used, Bob feels the bale walls may have been spared.

Due to the generally impenetrable nature of the walls they seemed to act as barriers to heat-flow in both beneficial and detrimental ways.  Bob had installed his solar PV array 10 feet from the bale structure. The PV panels were virtually unharmed due to the shielding nature of the bale walls. His wood-framed shop, situated approximately 30 feet from the framed portion of the residence, ended up burning to the ground from direct exposure to the heat of the fire. The drawback was that Bob felt the bale walls created an oven-like effect within the building, holding heat inside, keeping the temperature very high.  As a result, one of the losses was the family safe which was supposedly fire-proof.  It was unable to withstand the “heat-trap” surrounded and created by the bale walls.  From these accounts, It is clear that the bale walls have a very significant heat-shielding effect during a major fire event.

The entire structure was insured by Allstate Insurance.  Bob was honest with them at the time of insuring the building and did not hide the fact that part of the building incorporated bale walls.  Allstate did not seem to make a big deal of the fact either then or now.  It appears they are making a pay-out on the insurance policy.  This is good news to bale building owners everywhere.  An insurance company had the capacity to not focus on the fact that some of the exterior walls were made of straw and plaster.  It is not clear if they understood how stable the walls were during the fire since they did not collapse, like the rest of the structure.  The fact that the bale walls did not contribute to serious problems was probably one reason for the lack of focus.

Being a volunteer firefighter Bob was frustrated he could not help fight the fire that destroyed his own home.  He understood that following orders from his fellow firefighters to seek help for his smoke inhalation was the right thing to do.  When asked about how the fire was suppressed in the bale walls and why it took so long, it became clear that the ongoing smoldering was not going to stop on it’s own.  The walls needed to be broken up in order to access all of the smoldering spots.

It seems that there is a pattern among bale buildings that are engulfed by flames.  The walls remain standing as long as anyone is willing to let them stand.  The main reason they are taken down is to gain access to smoldering areas within the walls so as to eliminate any risk of spread and the accidental ignition of other fires elsewhere.  The fact that bale walls are very effective heat shields makes them good fire-separation wall candidates between living units, or uses, within a structure.  They remain stable throughout the fire event, which cannot be said of steel or wood-framed walls in low-rise residential or commercial construction.  The fact that they tend to smolder and require maintenance for days after the initial fire event costs money and resources, but weighed against the fact that they do not fail catastrophically means that they may be considered as life-safety elements in buildings with many uses and occupancies.

The lessons learned in this building are that bale walls are incredibly stable during a fire event, offer a thick shield to retard flame-spread, and are tough to dismantle, requiring many days and resources by the local fire department.  When put together it seems that the bale walls themselves had a much better track record than any other part of the structure.  Feel free to comment or add to the discussion by logging in and submitting your thoughts.

Bob says he will not rebuild with bales mainly due to the huge amount of labor involved.  He will probably choose to build with some form of ICF (insulated concrete form) and steel.  He and his family enjoyed their bale home, but the time and labor necessary do not seem as realistic the second time around.

All fires in bale buildings are felt throughout the community as a serious and deep loss.  Even though we do not wish for them there is a great deal to learn from each and every one.  We hope this account will help firefighters, insurers, designers and homeowners make the best decisions possible.  Please comment below and participate in the conversation.  We are interested in your thoughts.  Email the author with any specific question for the owner offline.