BigWallop wrote:

"Asher Hoskins" wrote in message
...

Hello.

Does anyone have any experience with straw bale construction? I'm
pondering options for a self-build at the moment and a wooden framed
house with bale infill looks interesting (mainly due to low U-value,
speed/simplicity of use and cost).

Has anyone here built a straw bale construction? (Or even better, worked
out how to fit one into the building regs!) There's a great deal of
enthusiastic information online from straw bale advocates but some more
dispassionate opinions would be nice.


Asher.



The more I'm reading about this type of build, the more I like it. The
basic types seem to be, really, just a timber frame with the straw wrapped
round it and rendered over. Very simple. Very effective. And very energy
efficient according to all the info' I've dug up. One owner in the USofA
says they have saved the cost of building the house in what they would have
paid in fuel bills over last twelve years. They also say that the build, in
their climate (temperate I think), is expected to last in excess of 120
years with only minor maintenance works.

Looking good for the strawbale housing market, me thinks. :-)


I think it could be incredibly effective. With 3ft thick walls at the
sort of ciondictivity lebvels of maybe high densiy polystyrene, there
would be almost no heatloss through the straw at all. Only the doors
windows ventilation and floor and roof would need actual attention paid.

It really is a hugely fast and energy efficient way to build IMHO.

wrote:

BigWallop wrote:


The more I'm reading about this type of build, the more I like it. The


Looking good for the strawbale housing market, me thinks. :-)


AIUI the basic problem with straw bale is that when render
deteriorates, or something allows water onto the straw, repairs must be
made rapidly else things deteriorate fast. And yer average jo isnt
nearly quick enough with repairs. So ideal for someone wililng to
inpsect it regularly and repair themselves promptly, but that just
doesnt describe most people.

Its the same for timber.


NT

Owain wrote:

The Natural Philosopher wrote:

Building in straw should be lioke building in blockwork.
And I should think expanding foam to hold door and window frames in
woould be appropiate.


Hold in with long wooden staves driven into the bales.

Not sure how to arrange for a wterproof skin though - breathable
membrane, air gap, metal lathe and render maybe?


Blue plastic held down with baler twine.

Owain

You know, SWMBO wants a summerhouse thing...I wonder if our farmer will
have some bales...

In message , Mike
writes
See

http://www.surreycc.gov.uk/sccwebsit...pWebPagesByTIT
LE_RTF/Manure+storage+and+disposal+advice?opendocument

I'll have a look tonight.

and other similar sites. As it says the exact intent of the new law is
still unresolved.

A recent DEFRA magazine told farmers not to spread fresh waste from equine
stables on fields for the time being, yet they still say it is okay in
www.defra.gov.uk/rural/horses/topics/tourism.htm

Spreading up to 250kg of nitrogen per hectare per annum from rotted dung
is permitted under the directive. This represents a tonnage far beyond
practicality with 25-50 tons being a normal rate (1.7kg N/ton)

In the meantime storing 250 cu metres of muck per horse for a year after
which it can be spread whilst keeping any outflow under control is a real
headache for many stables - and an eyesore for all.

Umm. You might need to check that figure. A dairy cow produces 40l/day
of faeces and urine.

I guess the biggest headache is storing under cover or finding fresh
sites each year. Local stables are still burning their waste with days
of persistent pong in light winds.

regards







--
Tim Lamb

In article ,
Tim Lamb wrote:
[snip]
Umm. You might need to check that figure. A dairy cow produces
40l/day of faeces and urine.

There's a large dairy farm just over the hill.
If the wind is right, the stink and the ammonia makes
your eyes water. On any nice foggy morning we will
generally hear the sound of a tractor working,
somewhere on his fields. Can't see it, but the smell
gives it away. Guess what he is doing.

--
Tony Williams.

The Natural Philosopher wrote:
wrote:

AIUI the basic problem with straw bale is that when render
deteriorates, or something allows water onto the straw, repairs must be
made rapidly else things deteriorate fast. And yer average jo isnt
nearly quick enough with repairs. So ideal for someone wililng to
inpsect it regularly and repair themselves promptly, but that just
doesnt describe most people.

Its the same for timber.

But with quite a different time scale. Wet timber lasts a few years,
wet straw lasts what, a few weeks?

NT

wrote:

The Natural Philosopher wrote:

wrote:


AIUI the basic problem with straw bale is that when render
deteriorates, or something allows water onto the straw, repairs must be
made rapidly else things deteriorate fast. And yer average jo isnt
nearly quick enough with repairs. So ideal for someone wililng to
inpsect it regularly and repair themselves promptly, but that just
doesnt describe most people.


Its the same for timber.


But with quite a different time scale. Wet timber lasts a few years,
wet straw lasts what, a few weeks?


Dunno. About 15 years for straw thatch, and up to 60 for reed?

That's fully exposed - but not dug-in-the-ground straw...

You have to look at what will decompose it.

Sodden straw in the ground is actually EATEN by things like nematodes.

Wod is attacked by fungi and wood biring insects etc.

Once in structure and even marginally drier than the ground, these
things don't happen.

Thatched rooves 'wear' more from constant pounding of water droplets for
example. Then build up of dust and dirt allows damp soil areas to
appeaar, and grass and other weeds and moss takes root...and the other
life then follows.

I would see the lifetime of a straw vbale wall doine decently as being
similar to timber - a couople of hundred years.

Maintenace would be a cinch. cut a hole, take our rotten, and stuff with
new straw and make good..






NT

The Natural Philosopher wrote:
Maintenace would be a cinch. cut a hole, take our rotten, and stuff with
new straw and make good..

You've got me humming "follow the yellow brick road" now...

Owain

wrote:
The straw has to be dry for efficient heating. I guess the horses
would leave it rather wet. Better to compost it.


On the other hand, this could eliminate the "how long will it last" question
about strawbale walls.
Just burn and replace bales as you go.

On 2005-06-01, Anna Kettle wrote:
Lime plaster of course

That's next on my list of things to investigate! Am I right in assuming
that a coat of lime mortar on the outside of the wall would need to be
balanced by a similarly breathable covering+paint on the inside of the
wall? Or given a typically dry, heated interior and a wet British winter
outside would this just allow water to migrate the wrong way, inwards?

I'd love to build a strawbale house too. A lime plastering friend of
mine who lives in North Wales has worked on several strawbale houses
via Barbara Jones (who is the Queen of strawbale in the UK)

There's a good guide (78 page PDF) to strawbale construction on her
website:

http://www.strawbalefutures.org.uk/

Buildings with a structural timber framework and straw infill are
easier to get planning permission for cos the calcs are easier to do
but I prefer buildings where the straw bales are loadbearing

Building regs were the main reason for thinking about a wood framed
house, although wood framing does mean that you can put a roof cover on
before stacking the bales - a very useful thing in the UK climate.


Asher.

--
asher http://domestic1.sjc.ox.ac.uk/~ahoskins/
asher AT crumbly DOT
[life in plastic, it's fantastic!] freeserve DOT co DOT uk

On 2005-06-01, Mike wrote:
I'm sure I read somewhere that the BBA was testing straw bales as used in
this purpose. Why not ask them if they did and if so what the results were.
If it passed this would have all the info you need for the building regs.

Is this the "British Board of Agrement" (http://www.bbacerts.co.uk/)? I
shall contact them. Googling reveals several large conventional
buildings using straw bale insulation so presumably some official specs
must exist.

I also found a note on one document saying that strawbale insulation is
treated with sodium borate to prevent rodent damage.


Asher.

--
asher http://domestic1.sjc.ox.ac.uk/~ahoskins/
asher AT crumbly DOT
[life in plastic, it's fantastic!] freeserve DOT co DOT uk

"The Natural Philosopher" wrote in message
...
Looking good for the strawbale housing market, me thinks. :-)


I think it could be incredibly effective. With 3ft thick walls

I think you've hit on a problem. Under Prescott's latest planning laws 3 ft
walls leaves you about 2 ft for the living space between them :-(

"Tim Lamb" wrote in message
...

A recent DEFRA magazine told farmers not to spread fresh waste from
equine
stables on fields for the time being, yet they still say it is okay in
www.defra.gov.uk/rural/horses/topics/tourism.htm

Spreading up to 250kg of nitrogen per hectare per annum from rotted dung
is permitted under the directive. This represents a tonnage far beyond
practicality with 25-50 tons being a normal rate (1.7kg N/ton)

Yes - but straw isn't currently classed like rotted dung under the new
regulations.


In the meantime storing 250 cu metres of muck per horse for a year after
which it can be spread whilst keeping any outflow under control is a real
headache for many stables - and an eyesore for all.

Umm. You might need to check that figure. A dairy cow produces 40l/day
of faeces and urine.

It's the horse bedding that's the problem. Horses usually have the good
sense to wait until they're away from their stables before ****ting
everywhere :-)



I guess the biggest headache is storing under cover or finding fresh
sites each year. Local stables are still burning their waste with days
of persistent pong in light winds.

I think that needs a licence now.

"Tony Williams" wrote in message
...
In article ,
Tim Lamb wrote:
[snip]
Umm. You might need to check that figure. A dairy cow produces
40l/day of faeces and urine.

There's a large dairy farm just over the hill.
If the wind is right, the stink and the ammonia makes
your eyes water. On any nice foggy morning we will
generally hear the sound of a tractor working,
somewhere on his fields. Can't see it, but the smell
gives it away. Guess what he is doing.

That's totally allowed provided you keep within the set limits. But for
some reason horse bedding straw has been reclassified as a different type of
waste.

"Asher Hoskins" wrote in message
...
On 2005-06-01, Mike wrote:
I'm sure I read somewhere that the BBA was testing straw bales as used
in
this purpose. Why not ask them if they did and if so what the results
were.
If it passed this would have all the info you need for the building
regs.

Is this the "British Board of Agrement" (http://www.bbacerts.co.uk/)? I
shall contact them.

Yes. Give them a phone and let us all know as this is obviously a topic a
lot of people are interested in. I was intending to build a stone barn
myself next summer but now wondering if straw might be easier.

In message , Tony Williams
writes
In article ,
Tim Lamb wrote:
[snip]
Umm. You might need to check that figure. A dairy cow produces
40l/day of faeces and urine.

There's a large dairy farm just over the hill.
If the wind is right, the stink and the ammonia makes
your eyes water. On any nice foggy morning we will
generally hear the sound of a tractor working,
somewhere on his fields. Can't see it, but the smell
gives it away. Guess what he is doing.

Hertfordshire is down to about 6 dairy farms in total so not much of an
issue here.

regards


--
Tim Lamb

In message , Tim Lamb
writes
In message , Mike
writes
See

http://www.surreycc.gov.uk/sccwebsit...pWebPagesByTIT
LE_RTF/Manure+storage+and+disposal+advice?opendocument

I'll have a look tonight.

Well I looked. As you say not very exact.

The purpose of the new regulations is to minimise the risk of nitrates
reaching water sources. Stable manure is no different from farmyard
manure in that respect and it is to be hoped that sense will prevail.

regards

--
Tim Lamb

In message , Tim Lamb
writes
In message , Mike
writes
See

http://www.surreycc.gov.uk/sccwebsit...pWebPagesByTIT
LE_RTF/Manure+storage+and+disposal+advice?opendocument

I'll have a look tonight.

Not agricultural and not yet subject to the usual derogations.


In the meantime storing 250 cu metres of muck per horse for a year
after
which it can be spread whilst keeping any outflow under control is a
real
headache for many stables - and an eyesore for all.

Umm. You might need to check that figure. A dairy cow produces
40l/day
of faeces and urine.

It's the horse bedding that's the problem. Horses usually have the
good
sense to wait until they're away from their stables before ****ting
everywhere :-)

Yes. I expect my DIY owners to collect it. I was querying the 250 cu
metres per
horse. Ours use 2or 3 regular bales per week during the winter only so
more like 10
cu. metres when chimbled up and wet.

The problem is that stables do not usually have spare land that can be
rested while
spread manure is absorbed.

regards

--
Tim Lamb

Here's a good way of learning about strawbale construction:
http://www.strawbalefutures.org.uk/courses.htm

Mike wrote:
"Tony Williams" wrote in message
...

In article ,
Tim Lamb wrote:
[snip]

Umm. You might need to check that figure. A dairy cow produces
40l/day of faeces and urine.

There's a large dairy farm just over the hill.
If the wind is right, the stink and the ammonia makes
your eyes water. On any nice foggy morning we will
generally hear the sound of a tractor working,
somewhere on his fields. Can't see it, but the smell
gives it away. Guess what he is doing.


That's totally allowed provided you keep within the set limits. But for
some reason horse bedding straw has been reclassified as a different type of
waste.


Horses=fox hunters=spawn of the devil upper calls toffs. Simple innit?

"Tim Lamb" wrote in message
...
In message , Tim Lamb
writes
In message , Mike
writes
See

http://www.surreycc.gov.uk/sccwebsit...pWebPagesByTIT
LE_RTF/Manure+storage+and+disposal+advice?opendocument

I'll have a look tonight.

Well I looked. As you say not very exact.

The purpose of the new regulations is to minimise the risk of nitrates
reaching water sources. Stable manure is no different from farmyard
manure in that respect and it is to be hoped that sense will prevail.


Or indeed from what comes out of the back of the horse or cow when it is
standing in the stream drinking.
But when did that matter to a bureaucrat ? :-)

On Fri, 03 Jun 2005 02:59:52 +0100, The Natural Philosopher
wrote:

Andrew Firebarce are giooid on structural calcs. The BCO will take their
word for it.

Don't know them but will squirrel the name away for future reference.
Where are they based?

Well you know Anna, there are two ways to do things: let the damp in and
arrange for it to get out outwards, or not let it in at all barely, and
let it migrate inwards and have a bit of internal heating and ventilation.

Your way is number one, but I see no problem with modern ways to
insulate/heat/ventilate and put a waterproof skin outside- you need that
anyway to get rid of the water that humans give off.

You got me thinking about the differences between the two building
methods and I came up with

Traditional:
Breatheable
Slightly flexible
Eco friendly ... man

Modern:
Impermeable
Rigid
High embodied energy

Straw bales sit firmly in the traditional zone on the ecofriendly
front, being bio and degradable. On reflection I can't see a problem
using them under an impermeable skin so maybe there is potential for
crossover there, but the design would have to be thought through with
care if they are to be loadbearing cos they will definitely not be
rigid and impermeable is only any good if it stays that way

Anna



~~ Anna Kettle, Suffolk, England
|""""| ~ Lime plaster repairs
/ ^^ \ // Freehand modelling in lime: overmantels, pargeting etc
|____| www.kettlenet.co.uk 01359 230642

On Fri, 03 Jun 2005 11:33:26 -0500, Asher Hoskins
wrote:

On 2005-06-01, Anna Kettle wrote:
Lime plaster of course

That's next on my list of things to investigate! Am I right in assuming
that a coat of lime mortar on the outside of the wall would need to be
balanced by a similarly breathable covering+paint on the inside of the
wall?

Yes thats a good plan though I expect TNP will come up with some
fiendishly hi tech ventilation system instead

You want to be careful once you start investigating lime. All your
friends will get glazed expressions as you start explaining the latest
wrinkle you've discovered

Which reminds me ... Anyone know anything about copperas? It may have
been used as a lime mortar pigment

Anna

~~ Anna Kettle, Suffolk, England
|""""| ~ Lime plaster repairs
/ ^^ \ // Freehand modelling in lime: overmantels, pargeting etc
|____| www.kettlenet.co.uk 01359 230642

On Fri, 03 Jun 2005 03:05:19 +0100, The Natural Philosopher
wrote:

Blue plastic held down with baler twine.

Baler twine aint what it used to be. I remember when it only came in
orange but the last bale I bought was blue

Disgusted of Pakenham on Sea

You know, SWMBO wants a summerhouse thing...I wonder if our farmer will
have some bales...

Oh good! It would make an excellent summerhouse and if you tell us all
about it I will be able to build a strawbale house by proxy

Anna

~~ Anna Kettle, Suffolk, England
|""""| ~ Lime plaster repairs
/ ^^ \ // Freehand modelling in lime: overmantels, pargeting etc
|____| www.kettlenet.co.uk 01359 230642

"Anna Kettle" wrote in message
...
On Fri, 03 Jun 2005 02:59:52 +0100, The Natural Philosopher
wrote:

Andrew Firebarce are giooid on structural calcs. The BCO will take their
word for it.

Don't know them but will squirrel the name away for future reference.
Where are they based?

Well you know Anna, there are two ways to do things: let the damp in and
arrange for it to get out outwards, or not let it in at all barely, and
let it migrate inwards and have a bit of internal heating and
ventilation.

Your way is number one, but I see no problem with modern ways to
insulate/heat/ventilate and put a waterproof skin outside- you need that
anyway to get rid of the water that humans give off.

You got me thinking about the differences between the two building
methods and I came up with

Traditional:
Breatheable
Slightly flexible
Eco friendly ... man

Modern:
Impermeable

Modern homes are impermeable? Please.

Rigid
High embodied energy

Straw bales sit firmly in the traditional zone on the ecofriendly
front, being bio and degradable. On reflection I can't see a problem
using them under an impermeable skin so maybe there is potential for
crossover there, but the design would have to be thought through with
care if they are to be loadbearing cos they will definitely not be
rigid and impermeable is only any good if it stays that way

Anna



~~ Anna Kettle, Suffolk, England
|""""| ~ Lime plaster repairs
/ ^^ \ // Freehand modelling in lime: overmantels, pargeting etc
|____| www.kettlenet.co.uk 01359 230642

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In message , Anna Kettle
writes
On Fri, 03 Jun 2005 03:05:19 +0100, The Natural Philosopher
wrote:

Blue plastic held down with baler twine.

Baler twine aint what it used to be. I remember when it only came in
orange but the last bale I bought was blue

Round balers use thinner twine. Alternatively you could buy that used
for Hesston (big) bales which is much thicker than the standard you are
familiar with.

Tale told of teacher returning gifted ball of baler twine and
plaintively asking *what happened to the short lengths with a knot at
the end?*

Disgusted of Pakenham on Sea

You know, SWMBO wants a summerhouse thing...I wonder if our farmer will
have some bales...

How many and where?

Oh good! It would make an excellent summerhouse and if you tell us all
about it I will be able to build a strawbale house by proxy

I think you are right to worry about the load bearing capability of
bales. I have no recent experience of the mini Hestons used in the TV
program but a stack of conventional bales 5metres high will squash the
bottom layer by up to 10% over 12 months storage.

regards
--
Tim Lamb

In article ,
Mike wrote:
[snip]
But for some reason horse bedding straw has been
reclassified as a different type of waste.

ISTR reading somewhere that horses don't catch BSE
themselves, but can be carriers of it. Since they
show no symptoms of BSE they would be undetectable
carriers.

--
Tony Williams.

Anna Kettle wrote:

On Fri, 03 Jun 2005 02:59:52 +0100, The Natural Philosopher
wrote:


Andrew Firebarce are giooid on structural calcs. The BCO will take their
word for it.


Don't know them but will squirrel the name away for future reference.
Where are they based?


Well you know Anna, there are two ways to do things: let the damp in and
arrange for it to get out outwards, or not let it in at all barely, and
let it migrate inwards and have a bit of internal heating and ventilation.

Your way is number one, but I see no problem with modern ways to
insulate/heat/ventilate and put a waterproof skin outside- you need that
anyway to get rid of the water that humans give off.


You got me thinking about the differences between the two building
methods and I came up with

Traditional:
Breatheable
Slightly flexible
Eco friendly ... man

Modern:
Impermeable
Rigid
High embodied energy

Straw bales sit firmly in the traditional zone on the ecofriendly
front, being bio and degradable. On reflection I can't see a problem
using them under an impermeable skin so maybe there is potential for
crossover there, but the design would have to be thought through with
care if they are to be loadbearing cos they will definitely not be
rigid and impermeable is only any good if it stays that way

You see Anna, I am an engineer, and I use whatever is to hand, that's
suitable and cheap.

400 years ago it was oak and wattle and daub and thatch. It looks nice,
but it has structural limitations.


Today we have a huge range of plastics, steels and other materials
available.

I am neither a traditionalist, not a modernist.

I don't like buildings with steel exoskeletons 'celebrating the use of
modern materials' any more than I like a house with no damp proof
course, no foundations, and which absolutely requires a breathable skin
to eradicate the rising damp. ;-)

I suppose if you gave me an unlimited budget I might come up with a
house thatched with carbon fibre :-)

I am by no means sure that slaked lime takes any less energy to make
than portland cement by the way.

Arguably we have more oil left than oak trees as well.

BUT we certainly have a LOT of straw around right now. And its
engineering properties are actually, in large bulk, pretty reasonable
for houses.

As far as breathable/not breathable goes, houses with humans generate
water. That has to be eradicated somehow.

In older houses with lower insulation, the water got to the walls and
condensed, making them damp, and the walls needed to breath outwards to
get rid of it. The walls got damp also because they had no DPC's. They
needed to be flexible because they subsided as they had no foundations.

They got round all that by having open fires with chimneys that sucked
out warm sticky air, in order to cause smog and pollution in the cities
and towns, and by having draughty doors to let fresh air in, and wearing
woollens - sometimes the same set - all winter. And by using flexible
breathable lime rendering on their flexible wattle and lathe ..

Today we go far far deeper with rigid steel reinforced foundations, so
our houses don't move, and with open fires being a bit polluting, we
have efficient boilers and hot water heating, and sealed double or
triple glazed windows and sealed doors and pack the walls with insulation.

The net effect of that is what water IS inside, stays there and will
condense on the coldest part of the house - generally just behind the
insulation. So we install vapour barriers on the inside.

And then punch holes in the structure to achieve enough 'background
ventilation/air change' to let the sticky fug out in a controlled way.

We probably use far LESS energy to heat our houses than we used to
actually.

As I said, I am not arguing particularly for or against either method,
as both on their way work, and both are adapated to the resources available.

My complaint about modern houses is their soullessness. My response has
been to construct a house to modern standards using a mixture of
whatever worked properly and looked good and felt right. I've got single
glazed leaded light french doors in a steel encased frame. For example.
The look and feel is Lutgyens, the construction is post war steel..in
this case. I've got an oak and softwood frame stuffed to the hilt with
rockwool. I've got a slate floor with UF heating. And open fires. And
fully wired Broadband and TV...

The appearance is very traditional, and the sound of a door slamming
tells me I am in a timber house, BUT I don't have the cold, damp and
fungal smells associated with most of our local ones, and the house is
rigid enough not to need flexible plastering, and ventilated enough not
to need breathable walls.


I really do think that there is a sensible discussion to be engaged in
about what is the overall best way to build a house today, and I don't
thing the building trade has a monopoly on the right ideas any more than
either of US do, and certainly the governement is only interested in
metting self imposed target that take very little account of the quality
of life to be had inside the little hutches and kennels that they are
committed to supplying us with.

OTOH I am really for the *most* part a very firm supporter of current
building regualtions. Apart from the Part P and disabled ones which are
politically instigated, and not a reflection on 'best practice' as such.


The best of the old and the best of the new is my motto.








Anna



~~ Anna Kettle, Suffolk, England
|""""| ~ Lime plaster repairs
/ ^^ \ // Freehand modelling in lime: overmantels, pargeting etc
|____| www.kettlenet.co.uk 01359 230642

Tim Lamb wrote:

In message , Anna Kettle
writes

On Fri, 03 Jun 2005 03:05:19 +0100, The Natural Philosopher
wrote:

Blue plastic held down with baler twine.


Baler twine aint what it used to be. I remember when it only came in
orange but the last bale I bought was blue


Round balers use thinner twine. Alternatively you could buy that used
for Hesston (big) bales which is much thicker than the standard you are
familiar with.

Tale told of teacher returning gifted ball of baler twine and
plaintively asking *what happened to the short lengths with a knot at
the end?*


Disgusted of Pakenham on Sea

You know, SWMBO wants a summerhouse thing...I wonder if our farmer will
have some bales...


How many and where?


Oh good! It would make an excellent summerhouse and if you tell us all
about it I will be able to build a strawbale house by proxy


I think you are right to worry about the load bearing capability of
bales. I have no recent experience of the mini Hestons used in the TV
program but a stack of conventional bales 5metres high will squash the
bottom layer by up to 10% over 12 months storage.

Thats marginally less than green oak shrinks across the grain in the
first 5 years then! ;-)


regards

The Natural Philosopher wrote:
wrote:

The Natural Philosopher wrote:

wrote:


AIUI the basic problem with straw bale is that when render
deteriorates, or something allows water onto the straw, repairs must be
made rapidly else things deteriorate fast. And yer average jo isnt
nearly quick enough with repairs. So ideal for someone wililng to
inpsect it regularly and repair themselves promptly, but that just
doesnt describe most people.


Its the same for timber.


But with quite a different time scale. Wet timber lasts a few years,
wet straw lasts what, a few weeks?


Dunno. About 15 years for straw thatch, and up to 60 for reed?

That's fully exposed - but not dug-in-the-ground straw...

Thats a fair point, though the conditions are significantly different.
A roof dries off and is well ventilated, both of these stop rot. But a
bale, once damp, would simply rot, with no drying and no airflow.


You have to look at what will decompose it.

Sodden straw in the ground is actually EATEN by things like nematodes.

Wod is attacked by fungi and wood biring insects etc.

Once in structure and even marginally drier than the ground, these
things don't happen.

Thatched rooves 'wear' more from constant pounding of water droplets for
example. Then build up of dust and dirt allows damp soil areas to
appeaar, and grass and other weeds and moss takes root...and the other
life then follows.

I would see the lifetime of a straw vbale wall doine decently as being
similar to timber - a couople of hundred years.

I wonder.

Maintenace would be a cinch. cut a hole, take our rotten, and stuff with
new straw and make good..

yes! no need for a builder there. I guess the problem then is if Jo
Public has a loadbearing strawbale house and doesnt maintain it, as
people tend to not do.


You cant make strawbale arches can you?? Would avoid a lot of timber...


NT

"Anna Kettle" wrote in message
...
You got me thinking about the differences between the two building
methods and I came up with

Traditional:
Breatheable
Slightly flexible
Eco friendly ... man

Modern:
Impermeable
Rigid
High embodied energy

Not sure I totally agree with this. Some modern Scandanvian and more
especially German timber structures are highly rigid and sealed yet I would
say are eco-friendly (and traditional)

"Anna Kettle" wrote in message
...
On Fri, 03 Jun 2005 03:05:19 +0100, The Natural Philosopher
wrote:

Blue plastic held down with baler twine.

Baler twine aint what it used to be. I remember when it only came in
orange but the last bale I bought was blue

Disgusted of Pakenham on Sea

You know, SWMBO wants a summerhouse thing...I wonder if our farmer will
have some bales...

Oh good! It would make an excellent summerhouse and if you tell us all
about it I will be able to build a strawbale house by proxy


Perhaps we should have a summercamp get together to experiment with the best
way of building one.
I volunteer my field and straw bales :-)

On Fri, 03 Jun 2005 11:33:26 -0500, Asher Hoskins
wrote:

That's next on my list of things to investigate! Am I right in assuming
that a coat of lime mortar on the outside of the wall would need to be
balanced by a similarly breathable covering+paint on the inside of the
wall?

Yes - but not underneath. DPCs are a good idea no matter what the technique
or era.

"Tony Williams" wrote in message
...
In article ,
Mike wrote:
[snip]
But for some reason horse bedding straw has been
reclassified as a different type of waste.

ISTR reading somewhere that horses don't catch BSE
themselves, but can be carriers of it. Since they
show no symptoms of BSE they would be undetectable
carriers.

Quite possibly. The problem is nobody seems to know why the regs have
changed - just that they have.
And of course most horses love exercising in streams which invariably lead
into reservoirs or rivers from which drinking water is taken so the whole
things a nonsense anyway.

On Sat, 04 Jun 2005 12:50:53 +0100, The Natural Philosopher
wrote:

You see Anna, I am an engineer, and I use whatever is to hand, that's
suitable and cheap.
400 years ago it was oak and wattle and daub and thatch. It looks nice,
but it has structural limitations.

All materials have structural limitations and the structural
limitations of these materials are not nearly so important as

1. The economic balance has changed from expensive transportation
costs and cheap labour to cheap transportation costs and expensive
labour

2. Big business cannot patent it so there will never be the marketing
push to sell it, improve techniques etc

Today we have a huge range of plastics, steels and other materials
available.

And very useful they are too

I am by no means sure that slaked lime takes any less energy to make
than portland cement by the way.

It doesn't have to be heated to nearly such a high temperature. There
aren't the economies of scale, but that is more to do with money than
energy

Arguably we have more oil left than oak trees as well.

That was true in the early middle ages too, so they took up tree
planting which is one of the reasons there are so many late medieval
and Tudor timber framed houses in Suffolk and why Henry and Elizabeth
could build fleets of ships. Trees are easy to plant

On a tangent, although some people are planting oaks today, I don't
think anyone is bending the saplings to get curved timber. If I were
planting oaks I would plant some bent ones

The walls got damp also because they had no DPC's.

The oldest houses were built in the optimum places where there were no
underground springs or problems with water runoff. That just wasn't
possible in town centres and everywhere from Georgian times onwards so
dealing with ground water became more of a priority.

My house is old enough to have no damp course and no rising damp. In
fact I am excited cos yesterday I pulled off the last bit of external
cement render (hurrah!) to expose the original 500+ year old sole
plate. If there were any damp problems it would not still be there

needed to be flexible because they subsided as they had no foundations.

Yes foundation technology is much better today

Today we go far far deeper with rigid steel reinforced foundations, so
our houses don't move, and with open fires being a bit polluting, we
have efficient boilers and hot water heating, and sealed double or
triple glazed windows and sealed doors and pack the walls with insulation.

The net effect of that is what water IS inside, stays there and will
condense on the coldest part of the house - generally just behind the
insulation. So we install vapour barriers on the inside.

And then punch holes in the structure to achieve enough 'background
ventilation/air change' to let the sticky fug out in a controlled way.

And lots of these things are improvements

We probably use far LESS energy to heat our houses than we used to
actually.

Oh I agree, except that they economised on energy input by living in
much less comfortable houses than we would be prepared to put up with
now

As I said, I am not arguing particularly for or against either method,
as both on their way work, and both are adapated to the resources available.

My complaint about modern houses is their soullessness. My response has
been to construct a house to modern standards using a mixture of
whatever worked properly and looked good and felt right.

The things I do to my house are constrained partly by it being a
listed building but more importantly by what I do for a living. I want
to understand the complete medieval building system and that means
dealing with the building repairs in a medieval way.

Mind you I'm also keen on electricity, central heating, chimneystacks
and glass so I'm not a complete purist and interfacing old and new
technologies is interesting to me too, hopefully combining 21st
century comfort with using materials which have low embodied energy
and low energy running costs in preference to fashionably hitech
products which are heavily marketed. Things which are not advertised
require more searching out and understanding, but thats OK, I like
doing that

I really do think that there is a sensible discussion to be engaged in
about what is the overall best way to build a house today

I do too, but strawbale construction will never hit the mass market
cos it takes up too much space. Insulating with hemp batts is probably
more realistic.

I'm getting interested in linseed oil paint which according to the
enthusiasts is very long lasting on external window and door frames
(15 years before repaint is needed) and only went out of fashion after
the last war cos cold pressed linseed oil was unavailable and boiled
linseed oil doesn't work so well. I will let you know the result of my
researches in 15 years time

the governement is only interested in
metting self imposed target that take very little account of the quality
of life to be had inside the little hutches and kennels that they are
committed to supplying us with.

Luckily, there are a lot of people for whom the way their house is
built is not important, it just has to be there and to be reasonably
comfortable

Oil prices are generally heading upwards and as they do, the low
energy input options will appeal more to housebuilders. I just like to
be ahead of the game

Anna

~~ Anna Kettle, Suffolk, England
|""""| ~ Lime plaster repairs
/ ^^ \ // Freehand modelling in lime: overmantels, pargeting etc
|____| www.kettlenet.co.uk 01359 230642

On Sat, 4 Jun 2005 22:43:23 +0100, "Mike" wrote:


"Anna Kettle" wrote in message
...
You got me thinking about the differences between the two building
methods and I came up with

Traditional:
Breatheable
Slightly flexible
Eco friendly ... man

Modern:
Impermeable
Rigid
High embodied energy

Not sure I totally agree with this. Some modern Scandanvian and more
especially German timber structures are highly rigid and sealed yet I would
say are eco-friendly (and traditional)

I suppose I would wriggle out of this by calling them crossover
products, where the best of the new and the old are combined. Its the
way building will have to go eventually

Anna


~~ Anna Kettle, Suffolk, England
|""""| ~ Lime plaster repairs
/ ^^ \ // Freehand modelling in lime: overmantels, pargeting etc
|____| www.kettlenet.co.uk 01359 230642

On Sat, 4 Jun 2005 22:45:02 +0100, "Mike" wrote:


"Anna Kettle" wrote in message
...
On Fri, 03 Jun 2005 03:05:19 +0100, The Natural Philosopher
wrote:

Blue plastic held down with baler twine.

Baler twine aint what it used to be. I remember when it only came in
orange but the last bale I bought was blue

Disgusted of Pakenham on Sea

You know, SWMBO wants a summerhouse thing...I wonder if our farmer will
have some bales...

Oh good! It would make an excellent summerhouse and if you tell us all
about it I will be able to build a strawbale house by proxy


Perhaps we should have a summercamp get together to experiment with the best
way of building one.
I volunteer my field and straw bales :-)

And I volunteer all the spare energy and time I have after doing the
day job. Which is none, sadly

Anna


~~ Anna Kettle, Suffolk, England
|""""| ~ Lime plaster repairs
/ ^^ \ // Freehand modelling in lime: overmantels, pargeting etc
|____| www.kettlenet.co.uk 01359 230642

Not only does lime burning require a much lower temperature than
Portland cement manufacture, the carbon dioxide driven off in the
limestone to quicklime reaction is reabsorbed from the atmosphere as
the lime mortar sets by carbonation. So, overall, lime mortar has a
lower climate change impact than Portland cement.

Oak trees are growing faster than they are being used, in Britain and
across the Continent. I'm growing some bent ones for you Anna - hope
you live to 150! It's no good saying there is more oil left than oak.
Oil doesn't grow on trees and the best guess is that oil production
will peak very soon, if it hasn't already, and from then on supply will
fall short of demand no matter how high the price goes. See
http://www.peakoil.net/

Linseed oil paint is lovely to use. It is the only paint I use on the
oak windows that I make, if they get painted at all. Get the Sweedish
Allback paint from Holkham Paints:
http://www.holkham.co.uk/linseedpaints/
or Peter Maitland-Hood makes it at The Real Paint and Varnish Co:
http://www.realpaints.com/

Interesting stuff about copperas at:
http://www.eng-h.gov.uk/archcom/proj...l97_8/2059.htm

We use straw to heat our house. It costs us 60p per bale delivered to
our barn.

On Sat, 4 Jun 2005 22:46:20 +0100, "Mike" wrote:

Yes - but not underneath. DPCs are a good idea no matter what the technique
or era.

Not necessarily under straw bale. You need drainage at the bottom of the
stack and a poly sheet DPC is likely to cause more trouble by trapping
water from above than it will solve by stopping "rising damp" from
below.

On Sat, 04 Jun 2005 12:52:17 +0100, The Natural Philosopher
wrote:

Thats marginally less than green oak shrinks across the grain in the
first 5 years then! ;-)

Only in a log cabin though. We don't use framing timber in a way that
causes the shrinkage to make overall dimensional changes. OK, so your
sole plate might end up 1/4" thinner, but your walls aren't going to
shrink downwards by a foot.