From this thread http://www.byggahus.se/forum/hemma-hos/124527-halmbalshus-med-trafasad-6.html#post1667466
This thread arose.
Because I was asked which were the early straw bale houses in Sweden. I have been studying this in practice since 2000. The first time I heard about clay houses was at an annual meeting with a folk high school around 1997, by a certain Maja Lindstedt. I will return to her another time. Anyway, I was immediately taken with the idea. Quite quickly when I started reading about clay, it became clear that it is the most common building material for houses throughout history. This is partly because it exists, even in places without trees, but also because of clay's special properties, which I will also return to another time.
Quite a few people are interested in clay and straw as building materials on a theoretical level, hence the thread. But it has also become quite a bit over the years in Sweden. My guess is that there are about 80 newly built (from the late 90s to now) clay houses, correct me if I'm wrong. Clusters are Skåne, the West Coast, and the area around Järna (where there are Hare Krishnas and anthroposophists, and more clay houses). I have visited about 20 clay houses in Sweden. I have helped build several of these, but not as an expert, rather there has always been an instructor, and they have usually been good, so it has mostly been educational. And who I am, that's not answered in a nutshell. I have no relevant education in this anyway. Just book smart. In my profile, there is a link to my website, it is a little more than half-finished, unfortunately, I have not published any of my texts about clay houses yet, even though I have two. A lot of other things have come up in between. But now I want to go through this again, for I have bought a house, and there I am planning to insulate with clay straw, and sometime in conjunction with that, I intend to make a section on my site about such things!
So I have no ready fundamentals to offer as an introduction, but I thought I'd post some various existing sources to start with. It’s not entirely wrong because that was precisely the question I was asked!
First up:
Straw instead of fiberglass
There is a noted house that is now taking shape on Skäve farm. Several major newspapers have been there and also TV. Maybe they should cobble together a press stand joke the construction workers when NU JÄRNA! comes to visit. And indeed, the house is interesting. Here a blend of old and new is being tested.
Straw is combined with lightweight concrete, the frame is assembled with wooden dowels, the foundation is honored, and maybe solar collectors will be placed on the roof. Low standard but high quality, architect Walter Druml has set as the title for the construction. Low standard, indeed, the night-time desperate will have to tiptoe down a staircase to the toilet. But also high quality. Simple materials with minimal risk of mold problems. Locally produced, the spruce has grown on Mikaelsgården and Vårdinge By and the straw was still waving in the wind while the house's frame began to take shape.
The background to the construction is that Skäve needed a residential house for the family that manages the milking on the farm. But there was a lack of funds. What to do? Walter Druml at Prisma architects in Järna had ideas on how the local resources could be utilized. Digging for the foundation, water, and sewage could be managed by themselves on the farm. Timber could be obtained from nearby farms and doors, windows, and more could be reclaimed from demolition houses in the area. And there was plenty of straw! Just make a little compromise on normal standards and it would probably balance economically and become an interesting, experimental build that fit well with biodynamic Skäve farm's alternative direction. Walter wanted to build the house in so-called timber framing, a technique he had previously tested together with the carpenter Johannes Kästel at the construction of a boathouse at Vårdinge By.
It is an old technique used in old barns and outbuildings and in the roof trusses of, for example, apartment buildings. The wood is joined into a frame using wooden dowels and struts without a single nail. Johannes Kästel learned the timber framing technique in the USA where it has experienced a renaissance in the past 25 years. There it is primarily focused on residential houses and is called timber framing. It is also being developed, with tradition as a basis but with, among other things, an ecological perspective and innovative thinking in terms of, for example, cladding materials and the reuse of old timber. During the summer, a course in timber frame construction was held at Vårdinge By with Johannes as a teacher. The course participants then manufactured the frame for the house. The house is built in two stories totaling 135 square meters. Walls will consist of compressed straw bales, about 50 cm thick. On the outside, the straw is plastered and the inside will be covered with wood paneling. Most of the beautiful wood construction will be visible inside the house.
On the ground floor of the house will be the entrance, kitchen, and living room, and upstairs, four bedrooms. The wet area, meaning the toilet and washroom, is built as an annex to the house and in lightweight concrete. In this way, a lot of pipework inside the house is avoided. Toilet waste will be separated and the urine connected to the farm's other urine management while the feces will probably be composted. Heating will be via a wood-fired kitchen stove placed in the middle of the house. It can also be used for cooking. Additionally, the solar panels will contribute to the heating.
Copied by Järnabron
This thread arose.
Because I was asked which were the early straw bale houses in Sweden. I have been studying this in practice since 2000. The first time I heard about clay houses was at an annual meeting with a folk high school around 1997, by a certain Maja Lindstedt. I will return to her another time. Anyway, I was immediately taken with the idea. Quite quickly when I started reading about clay, it became clear that it is the most common building material for houses throughout history. This is partly because it exists, even in places without trees, but also because of clay's special properties, which I will also return to another time.
Quite a few people are interested in clay and straw as building materials on a theoretical level, hence the thread. But it has also become quite a bit over the years in Sweden. My guess is that there are about 80 newly built (from the late 90s to now) clay houses, correct me if I'm wrong. Clusters are Skåne, the West Coast, and the area around Järna (where there are Hare Krishnas and anthroposophists, and more clay houses). I have visited about 20 clay houses in Sweden. I have helped build several of these, but not as an expert, rather there has always been an instructor, and they have usually been good, so it has mostly been educational. And who I am, that's not answered in a nutshell. I have no relevant education in this anyway. Just book smart. In my profile, there is a link to my website, it is a little more than half-finished, unfortunately, I have not published any of my texts about clay houses yet, even though I have two. A lot of other things have come up in between. But now I want to go through this again, for I have bought a house, and there I am planning to insulate with clay straw, and sometime in conjunction with that, I intend to make a section on my site about such things!
So I have no ready fundamentals to offer as an introduction, but I thought I'd post some various existing sources to start with. It’s not entirely wrong because that was precisely the question I was asked!
First up:
Straw instead of fiberglass
There is a noted house that is now taking shape on Skäve farm. Several major newspapers have been there and also TV. Maybe they should cobble together a press stand joke the construction workers when NU JÄRNA! comes to visit. And indeed, the house is interesting. Here a blend of old and new is being tested.
Straw is combined with lightweight concrete, the frame is assembled with wooden dowels, the foundation is honored, and maybe solar collectors will be placed on the roof. Low standard but high quality, architect Walter Druml has set as the title for the construction. Low standard, indeed, the night-time desperate will have to tiptoe down a staircase to the toilet. But also high quality. Simple materials with minimal risk of mold problems. Locally produced, the spruce has grown on Mikaelsgården and Vårdinge By and the straw was still waving in the wind while the house's frame began to take shape.
The background to the construction is that Skäve needed a residential house for the family that manages the milking on the farm. But there was a lack of funds. What to do? Walter Druml at Prisma architects in Järna had ideas on how the local resources could be utilized. Digging for the foundation, water, and sewage could be managed by themselves on the farm. Timber could be obtained from nearby farms and doors, windows, and more could be reclaimed from demolition houses in the area. And there was plenty of straw! Just make a little compromise on normal standards and it would probably balance economically and become an interesting, experimental build that fit well with biodynamic Skäve farm's alternative direction. Walter wanted to build the house in so-called timber framing, a technique he had previously tested together with the carpenter Johannes Kästel at the construction of a boathouse at Vårdinge By.
It is an old technique used in old barns and outbuildings and in the roof trusses of, for example, apartment buildings. The wood is joined into a frame using wooden dowels and struts without a single nail. Johannes Kästel learned the timber framing technique in the USA where it has experienced a renaissance in the past 25 years. There it is primarily focused on residential houses and is called timber framing. It is also being developed, with tradition as a basis but with, among other things, an ecological perspective and innovative thinking in terms of, for example, cladding materials and the reuse of old timber. During the summer, a course in timber frame construction was held at Vårdinge By with Johannes as a teacher. The course participants then manufactured the frame for the house. The house is built in two stories totaling 135 square meters. Walls will consist of compressed straw bales, about 50 cm thick. On the outside, the straw is plastered and the inside will be covered with wood paneling. Most of the beautiful wood construction will be visible inside the house.
On the ground floor of the house will be the entrance, kitchen, and living room, and upstairs, four bedrooms. The wet area, meaning the toilet and washroom, is built as an annex to the house and in lightweight concrete. In this way, a lot of pipework inside the house is avoided. Toilet waste will be separated and the urine connected to the farm's other urine management while the feces will probably be composted. Heating will be via a wood-fired kitchen stove placed in the middle of the house. It can also be used for cooking. Additionally, the solar panels will contribute to the heating.
Copied by Järnabron
Building houses out of straw bales seems pretty twisted to me.
OK, there are straw bales available, but use them for the livestock to eat or lie in.
But why build houses out of them? Just because it's cheap?
Why not just as well build the houses out of cardboard then?
On the other hand, the genuine clay houses, or maybe they're called earth houses, make a bit more sense.
See here for fine building tradition:
http://www.dn.se/bostad/i-halland-vaxer-det-hus-ur-akerjorden
http://www.epochtimes.se/articles/2007/08/18/12966.html
PS
Anyone want to guess how many bugs are in a straw bale?
1,000, 10,000, 100,000 or 1,000,000?
OK, there are straw bales available, but use them for the livestock to eat or lie in.
But why build houses out of them? Just because it's cheap?
Why not just as well build the houses out of cardboard then?
On the other hand, the genuine clay houses, or maybe they're called earth houses, make a bit more sense.
See here for fine building tradition:
http://www.dn.se/bostad/i-halland-vaxer-det-hus-ur-akerjorden
http://www.epochtimes.se/articles/2007/08/18/12966.html
PS
Anyone want to guess how many bugs are in a straw bale?
1,000, 10,000, 100,000 or 1,000,000?
Did you read the link? It was insulated with leca.haavard said:
Pests live on living material. Then they crawl out if they can. I had a lot of pests on the currants this summer, so I picked them and spread the berries out on a large cardboard, most of them ran awayhaavard said:
Which link? I didn't see anything about leca in KOW's links?Chaan said:
The articles are from before 2010 when the new energy requirements took effect. The last I read about these houses was that they can't build more without solving the energy issues. Maybe that's where the leca comes in?
But will the leca balls survive the tamping?
It says in the article from 2009 that they have it, so it was probably well-designed from the start. A good architect is probably two years ahead
Construction: Reinforced concrete slab, outer walls in clay and leca at the gable tip and leca in interior walls
Construction: Reinforced concrete slab, outer walls in clay and leca at the gable tip and leca in interior walls
We may still agree that it's a bit unusual to build houses out of anything just because it happens to be available.
Just because it is "natural" doesn't mean it is good. Compare stewed fly agaric with meatballs.
And of course, I don't know, but probably there are at least a hundred million small insects in a straw bale. Haavard's comment "Why would there be insects in the straw? There's nothing there for them to live on" is interesting.
Haavard, do you know what cows live on?
The point with ruminants, like cows, is that they can utilize the nutrients in pure cellulose, such as hay and straw. You can even feed them newspaper.
Just because it is "natural" doesn't mean it is good. Compare stewed fly agaric with meatballs.
And of course, I don't know, but probably there are at least a hundred million small insects in a straw bale. Haavard's comment "Why would there be insects in the straw? There's nothing there for them to live on" is interesting.
Haavard, do you know what cows live on?
The point with ruminants, like cows, is that they can utilize the nutrients in pure cellulose, such as hay and straw. You can even feed them newspaper.
It mentions leca in gables and interior walls. The walls themselves probably don't have any leca.Chaan said:
From GP in November:
http://www.gp.se/bostad/inredningarkitektur/1.1124362-flodande-ljus-i-jordhusens-mekka
They therefore do not meet today's requirements. (But I assume the regulations are written by people who only think halfway, so perhaps they should be approved.)
Cows do not live on straw. They CANNOT live on (untreated) straw!KnockOnWood said:
To be able to extract the little that is in the straw, it must be treated with lye. I remember the lye vat in my grandfather's cowshed, but when I was little, they had stopped using it, so I've never seen the process.
(You probably can't feed them with newspapers either; if that were the case, someone would have done it.)
Hay is something completely different. It is dried grass with lots of nutrients. So you can't build hay houses.
As mentioned, there's nothing for bugs to live on in straw. (It’s, of course, different if the straw is lying outside and gets wet. Then it starts to rot, and nutrients are released.)
P.S.: An agronomist at least knows a little about what cows live on...
Yes, that was interesting.
This must be due to the insulation in the internal walls, it’s an ad hoc solution for Sweden, it's a construction technique that is very unusual here.
- In the fall, these houses should retain heat a little longer and in the summer they should stay a bit cooler. But we don't experience a big difference compared to a regular house, says Göran.
So the insulation in the internal walls means you don't get the temperature-regulating effect of massive walls. The conclusion is that it’s not suitable for this climate.
This must be due to the insulation in the internal walls, it’s an ad hoc solution for Sweden, it's a construction technique that is very unusual here.
- In the fall, these houses should retain heat a little longer and in the summer they should stay a bit cooler. But we don't experience a big difference compared to a regular house, says Göran.
So the insulation in the internal walls means you don't get the temperature-regulating effect of massive walls. The conclusion is that it’s not suitable for this climate.
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There is truly a difference between hay and straw. Straw contains basically no nutrients as hay does.
The claim that cows can live on cardboard might be possible for a while but is hardly suitable and in no way proves that there would be lots of critters in straw as was the original claim.
Straw has been used as a building material/insulation for a long time, and it is encapsulated in the construction, so any potential small animals are unlikely to be a problem in any case.
The claim that cows can live on cardboard might be possible for a while but is hardly suitable and in no way proves that there would be lots of critters in straw as was the original claim.
Straw has been used as a building material/insulation for a long time, and it is encapsulated in the construction, so any potential small animals are unlikely to be a problem in any case.
This is a really interesting Off Topic discussion! At least it’s not about building houses.
What is hay and what is straw?
In my world, hay is grass with possibly seeds (seeds = protein and fat).
Nowadays, when farmers cut the grass every fourteen days, there probably isn’t much seed in the hay for the most part.
Straw = grass, wheat, rye, barley, timothy grass, oats, meadow foxtail, bentgrass or whatever it may be that grows, where the seeds have been threshed out, so only the stalk remains.
Am I somewhat right so far, Haavard (I got the impression you were an agronomist)?
For many years, before we had to put down our horse due to illness, it was mainly fed with grass seed straw.
It was prone to laminitis and couldn’t tolerate richer feed.
Anyway, what does straw contain? Well, cellulose.
Straw contains lots of nutrients in the form of cellulose, which the microbes in horses' and cows' stomachs can break down and convert into sugars that mammals can utilize.
That’s why we have cattle! To convert "worthless" grasslands into high-value fat and protein.
Have a nice weekend! Hopefully with a good steak of "nature meat."
What is hay and what is straw?
In my world, hay is grass with possibly seeds (seeds = protein and fat).
Nowadays, when farmers cut the grass every fourteen days, there probably isn’t much seed in the hay for the most part.
Straw = grass, wheat, rye, barley, timothy grass, oats, meadow foxtail, bentgrass or whatever it may be that grows, where the seeds have been threshed out, so only the stalk remains.
Am I somewhat right so far, Haavard (I got the impression you were an agronomist)?
For many years, before we had to put down our horse due to illness, it was mainly fed with grass seed straw.
It was prone to laminitis and couldn’t tolerate richer feed.
Anyway, what does straw contain? Well, cellulose.
Straw contains lots of nutrients in the form of cellulose, which the microbes in horses' and cows' stomachs can break down and convert into sugars that mammals can utilize.
That’s why we have cattle! To convert "worthless" grasslands into high-value fat and protein.
Have a nice weekend! Hopefully with a good steak of "nature meat."
You are so right!Chaan said:
The idea that having a large heat storage capacity in the building construction would somehow be more energy-efficient is a misconception.
Energy leaks out and energy must be supplied somehow.
If the energy transport is slightly slowed down in "energy-storing" clay walls it doesn't affect the need for energy supply.
More than for short periods, perhaps hours.
Just as the heat-retention walls delay the cooling of the dwelling,
they also delay the heating when the sun shines or the fire is burning.