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Concrete block wall art

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meow...@care2.com

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May 3, 2006, 3:48:47 PM5/3/06
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I wrote this for another thread, but I think it deserves its own...

Finally you can make your own concrete blocks if you want, need a
simple wood frame on a flat sheet, line it with polythene, and pour in
load after load. A 4x8 mould is 2 m^2 or so of blocks, so with 9"
blocks you can work out what you'd save.

The best thing about diy blocks is you can make them any design you
want. You can let the kids arrange brick rubble in them first for
decoration (flat side of brick pieces down), you can sprinkle the mould
with coloured stone chippings, or use coloured glass if you want it to
sparkle. Put a thin layer if white cement in if you want white but to
never need to paint it. Or if you want to make it even more unusual you
can make those blocks any interlocking shape you can think of. You can
also cast blocks for the wall top and ends with moulded in decoration,
eg straight framing, egg and dart, whatever you can make or find. Also
you can cast cubby holes in a few blocks for trailing strawberries, etc
etc etc

If you take a look at the famous concrete castle, you'll see what a
remarkably artistic material concrete blockwork can be. Check out the
2nd and 3rd pics here for a start:
http://www.architecture.com/go/Architecture/Also/VandA_5185.html
Theres much more intersting stuff on that castle, just ran out of
google time.

For rectangular blocks, a single 4'x8' mould will make 30 blocks of
8.25" x 14" in one pour, of whatever thickness you want. This uses 2"
thick perimeter wood and 3/4" thick dividers. And of course block
dimensions can be whatever you want, as long as theyre no bigger than
4'x8' apiece!


NT

Chris Bacon

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May 3, 2006, 4:35:20 PM5/3/06
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meow2222 wrote

> Finally you can make your own concrete blocks if you want, need a
> simple wood frame on a flat sheet, line it with polythene, and pour in
> load after load. A 4x8 mould is 2 m^2 or so of blocks, so with 9"
> blocks you can work out what you'd save.

Why make blocks when you can cast whole walls in stages?

Ian Stirling

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May 3, 2006, 4:55:21 PM5/3/06
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Why cast walls in stages, when you can cast walls in one?
Cast the slab for the floor.
Level it, get it nice and flat, then cast the other walls on it, and tip
them up into place.

Guy King

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May 3, 2006, 6:03:58 PM5/3/06
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The message <445918b9$0$2547$ed26...@ptn-nntp-reader02.plus.net>
from Ian Stirling <ro...@mauve.demon.co.uk> contains these words:

> Why cast walls in stages, when you can cast walls in one?
> Cast the slab for the floor.
> Level it, get it nice and flat, then cast the other walls on it, and tip
> them up into place.

Easy to do the damp-proofing, too. While the house is on its side, paint
one "wall" with rubbery masticy stuff then flip it over.

--
Skipweasel
Pay no attention to that man behind the curtain.

Rob Morley

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May 3, 2006, 9:06:16 PM5/3/06
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In article <445918b9$0$2547$ed26...@ptn-nntp-reader02.plus.net>

Ian Stirling <ro...@mauve.demon.co.uk> wrote:
> Chris Bacon <chris...@thai.com> wrote:
> > meow2222 wrote
> >> Finally you can make your own concrete blocks if you want, need a
> >> simple wood frame on a flat sheet, line it with polythene, and pour in
> >> load after load. A 4x8 mould is 2 m^2 or so of blocks, so with 9"
> >> blocks you can work out what you'd save.
> >
> > Why make blocks when you can cast whole walls in stages?
>
> Why cast walls in stages, when you can cast walls in one?
>
Because you need a lot less shuttering if you do it in stages.

Mike Halmarack

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May 4, 2006, 3:10:24 AM5/4/06
to
On 3 May 2006 22:35:20 +0200, Chris Bacon <chris...@thai.com>
wrote:

Ah! To block or not to block? That is the question.
I wondered where I'd seen the name before. :)
--
Regards,
Mike Halmarack

Drop the (EGG) to email me.

Ian Stirling

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May 4, 2006, 4:00:46 AM5/4/06
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Not much less.
You cast it on the floor slab, so you only need 30cm or whatever of
shuttering round the edge, then tip it up vertical.

Chris Bacon

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May 4, 2006, 4:15:37 AM5/4/06
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Ian Stirling wrote:
> Rob Morley wrote:
>> Ian Stirling wrote:

>>> Chris Bacon wrote:
>>>> meow2222 wrote
>>>>> Finally you can make your own concrete blocks if you want, need a
>>>>> simple wood frame on a flat sheet, line it with polythene, and pour in
>>>>> load after load. A 4x8 mould is 2 m^2 or so of blocks, so with 9"
>>>>> blocks you can work out what you'd save.
>>>> Why make blocks when you can cast whole walls in stages?
>>> Why cast walls in stages, when you can cast walls in one?
>>>
>> Because you need a lot less shuttering if you do it in stages.
>
> Not much less.
> You cast it on the floor slab, so you only need 30cm or whatever of
> shuttering round the edge, then tip it up vertical.

How do you "tip it up vertical"? How do you join corners? What
about internal walls?

meow...@care2.com

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May 4, 2006, 4:26:12 AM5/4/06
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Appearance of course. I did just explain that in a fair bit of detail
in the post above. Poured walls are not pretty.


NT

Weatherlawyer

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May 4, 2006, 4:28:34 AM5/4/06
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Ian Stirling wrote:
>
>... then tip it up vertical.
>
That's the easy bit, is it?

All this has been done for millenia. Or do you think prefabs are
something new?

What I'd like to design is a scoop that takes buckets full of molten
lava and work it into some sort of mass production instant maonry. It
would save a fortune in greenhouse emission and help prevent resources
being swallowed up in the flow from the suitable volcanoes.

Not exactly a steady stream of work but an extremely interestin on if
sporadic. Believe it or not we do have the technology. But moving it to
place at the time in time would be difficult.

Mike Halmarack

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May 4, 2006, 4:27:39 AM5/4/06
to
On 04 May 2006 08:00:46 GMT, Ian Stirling <ro...@mauve.demon.co.uk>
wrote:

ISTM the essential point about the OP's posting was the potential for
modeling and decorative effect. Achieving this level of design on a
monolithic slab would be quite an undertaking.

Chris Bacon

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May 4, 2006, 4:31:26 AM5/4/06
to

Block walls are at least as bad! Both these things are
better rendered.

Mike Halmarack

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May 4, 2006, 4:48:21 AM5/4/06
to
On 4 May 2006 10:31:26 +0200, Chris Bacon <chris...@thai.com>
wrote:

>meow...@care2.com wrote:

That's a silly thing to say in the context of the subject. You really
do resent difference of opinion don't you?
It gets right under your rind and causes your statements to become
rasher and rasher. :-)

Chris Bacon

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May 4, 2006, 5:03:48 AM5/4/06
to
Mike Halmarack wrote:

> Chris Bacon wrote:
>> meow...@care2.com wrote:
>>> Chris Bacon wrote:
>>>> meow2222 wrote
>>>>> Finally you can make your own concrete blocks if you want, need a
>>>>> simple wood frame on a flat sheet, line it with polythene, and pour in
>>>>> load after load. A 4x8 mould is 2 m^2 or so of blocks, so with 9"
>>>>> blocks you can work out what you'd save.
>>>> Why make blocks when you can cast whole walls in stages?
>>> Appearance of course. I did just explain that in a fair bit of detail
>>> in the post above. Poured walls are not pretty.
>> Block walls are at least as bad! Both these things are
>> better rendered.
>
> That's a silly thing to say in the context of the subject.

It wasn't in the context of the subject, though, was it. However,
if you want it to be, I should say that casting walls would make
it easier to get an artistic effect (e.g. by using moulds) than
it would be to get an effect using blockwork.

> You really do resent difference of opinion don't you?

No. I resent lots of things, but difference of opinion (where
one opinion does not fly in the face of fact) is not one. Perhaps
I should add that this reply is not in the context of the subject
of this post, or necessarily your statement.


> It gets right under your rind and causes your statements to become
> rasher and rasher. :-)

Oh dear oh dear.

Mike Halmarack

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May 4, 2006, 5:11:08 AM5/4/06
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On 4 May 2006 11:03:48 +0200, Chris Bacon <chris...@thai.com>
wrote:
>Oh dear oh dear.

Just thought it might be one you'd never heard before. :)

Ian Stirling

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May 4, 2006, 5:30:29 AM5/4/06
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The design is the fun bit.
Obviously, in order to tip it up, you need a largish crane, or a really
strong back (or a really small building).

As an example, let's say we've got a 3*3m slab, and want 2.5m high
walls 30cm thick.

First pour the slab.
Now, cast one 2.2m*2.5m slab on one corner, 30cm from the edge.
Tip it up, and you've got the door-side wall.
Now, cast a 2.7m*2.5m(with a 10cm fall on the top) slab on the adjacent side,
30cm from the edge again, tip up and bolt to the other wall.
Do the same with a 2.7*2.4m slab, and bolt it to side wall.
Repeat with a 2.4*2.5m(again, with a 9cm fall on the top) slab, and
you've got most of it up.
All you now need to do is to cast a 30cm*30cm pillar to finish off the
side adjacent to the door, and add a roof.

Putting windows in before now is probably a good plan too.

You can get horribly fancy with this sort of technique, if you don't use
the bare slab to cast on, but make large earth moulds to pour into,
including curved walls, ...

And if you want, you can get as fancy as you like on the inside.
For example, spraying on blobs of different colours of concrete, then
immediately pouring the main slab, or text, or mosaic, ...
The outside can be smooth, polished just before it sets, have harling
(throw gravel on), ...

It is a fairly rapid, and versatile technique.
There are probably ways to make the wall erection simpler, one that
springs to mind is simple hinges, cast into the walls, so you don't have
to worrry about securing the bottom while lifting.

The weight is of course a problem - for this small shed, the longest
side weighs 2 tons, which is fine with relatively trivial equipment - a
couple of 6*6's in an a-frame, some rope, and a block and tackle.
For larger walls, it gets problematical.

Guy King

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May 4, 2006, 5:49:19 AM5/4/06
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The message <4459b829$1...@newsgate.x-privat.org>
from Chris Bacon <chris...@thai.com> contains these words:

> > Not much less.
> > You cast it on the floor slab, so you only need 30cm or whatever of
> > shuttering round the edge, then tip it up vertical.

> How do you "tip it up vertical"? How do you join corners? What
> about internal walls?

These are left as exercises for the reader.

Guy King

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May 4, 2006, 5:51:35 AM5/4/06
to
The message <4459bbde$1...@newsgate.x-privat.org>

from Chris Bacon <chris...@thai.com> contains these words:

> Block walls are at least as bad! Both these things are
> better rendered.

The t'ween house walls in our terrace are poured - I'm facing one now.
Once semi-skimmed[1] and properly papered with crosslining it's fine.
Probably the flattest wall I've seen in years.

[1] Most of the concrete is just bare sized concrete, but where it's a
bit low it's been skimmed. Perhaps 20% of the area is actually covered
in plaster.

Guy King

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May 4, 2006, 5:58:23 AM5/4/06
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The message <4459c9b5$0$2540$ed26...@ptn-nntp-reader02.plus.net>

from Ian Stirling <ro...@mauve.demon.co.uk> contains these words:

> You can get horribly fancy with this sort of technique, if you don't use


> the bare slab to cast on, but make large earth moulds to pour into,
> including curved walls, ...

I've always wanted a dome-house (domus?) made by spraying concrete onto
inflatable domes with re-bar woven over 'em. Use aerated concrete and
they'd be insulating, strong and beautiful. Blank off a segment and when
it's down you could do several intersecting domes to give extra side
rooms.

Mike Halmarack

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May 4, 2006, 7:00:22 AM5/4/06
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On Thu, 4 May 2006 10:58:23 +0100, Guy King <guy....@zetnet.co.uk>
wrote:

I designed one of these in 1975. It was intended to be built by a
movable shutter on the end of a pivoting trammel beam. The
intersecting domes would be more easily built using the inflateable
method. Is it the woven re-bar that prevents the inflatable formers
from distorting under the weight of concrete?
I wonder what the multi-storey potential would be?

Chris Bacon

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May 4, 2006, 7:22:22 AM5/4/06
to
Guy King wrote:
> I've always wanted a dome-house (domus?) made by spraying concrete onto
> inflatable domes with re-bar woven over 'em. Use aerated concrete and
> they'd be insulating, strong and beautiful. Blank off a segment and when
> it's down you could do several intersecting domes to give extra side
> rooms.

You are a teletubby and ICMFTT.

Message has been deleted

Helen Deborah Vecht

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May 4, 2006, 9:02:26 AM5/4/06
to
Guy King <guy....@zetnet.co.uk>typed

> I've always wanted a dome-house (domus?) made by spraying concrete onto
> inflatable domes with re-bar woven over 'em. Use aerated concrete and
> they'd be insulating, strong and beautiful. Blank off a segment and when
> it's down you could do several intersecting domes to give extra side
> rooms.

Haven't you got a portable nylon trifin conjoined domus?

--
Helen D. Vecht: helen...@zetnet.co.uk
Edgware.

Guy King

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May 4, 2006, 7:39:42 AM5/4/06
to
The message <29nj529fag7tglt3g...@4ax.com>
from Mike Halmarack <...> contains these words:

> Is it the woven re-bar that prevents the inflatable formers
> from distorting under the weight of concrete?

I shouldn't think so, just air pressure. You'd probably have to put a
thin skin of concrete on first and let it harden before adding the rest.

Guy King

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May 4, 2006, 9:39:54 AM5/4/06
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The message <4E21B70B4B%brian...@lycos.co.uk>
from <m...@privacy.net> contains these words:

> You're after a vandal proof permanent model of that tent?

Got it in one! Though scaled up about 100% or perhaps 200%.

Guy King

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May 4, 2006, 9:39:21 AM5/4/06
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The message <4459...@newsgate.x-privat.org>

from Chris Bacon <chris...@thai.com> contains these words:

> You are a teletubby and ICMFTT.

Can't be - they've all got things sticking out of the tops of their
heads. Mine's glassy smooth and unadorned.

Ian Stirling

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May 4, 2006, 12:07:47 PM5/4/06
to

They can be - it just depends on how much care you take with the
mould you pour into.

Owain

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May 4, 2006, 1:16:12 PM5/4/06
to
Guy King wrote:
> Chris Bacon contains these words:

>>You are a teletubby and ICMFTT.

I think he's been quaffing those homeopathic medicines again ...

> Can't be - they've all got things sticking out of the tops of their
> heads. Mine's glassy smooth and unadorned.

You could try skull implants - a cross between dentistry and body piercing.

Owain


Guy King

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May 4, 2006, 4:31:39 PM5/4/06
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The message <114676440...@doris.uk.clara.net>
from Owain <owain...@stirlingcity.coo.uk> contains these words:


> > Can't be - they've all got things sticking out of the tops of their
> > heads. Mine's glassy smooth and unadorned.

> You could try skull implants - a cross between dentistry and body piercing.

That'd upset the little man who lives inside my head. At the moment he's
busy winding all my hair in from my scalp and shoving it out of my ears
and nostrils.

Rob Morley

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May 4, 2006, 9:50:44 PM5/4/06
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In article <4459b4ae$0$2548$ed26...@ptn-nntp-reader02.plus.net>
I thought we were talking about casting in situ. DIY slabs is an
interesting idea for sheds as well as plain (or decorative) walls.

Rob Morley

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May 4, 2006, 9:50:44 PM5/4/06
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In article <4459b829$1...@newsgate.x-privat.org>

Chris Bacon <chris...@thai.com> wrote:
> Ian Stirling wrote:
<snip>

> > You cast it on the floor slab, so you only need 30cm or whatever of
> > shuttering round the edge, then tip it up vertical.
>
> How do you "tip it up vertical"?

Did you not see that program about building Stonehenge?

> How do you join corners?

Leave some rebar sticking out the ends, tie/weld it together and pour
concrete over it.

> What about internal walls?
>
Why would you want reinforced concrete internal walls?

Mike Halmarack

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May 5, 2006, 5:27:09 AM5/5/06
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On Thu, 4 May 2006 21:31:39 +0100, Guy King <guy....@zetnet.co.uk>
wrote:

>The message <114676440...@doris.uk.clara.net>


>from Owain <owain...@stirlingcity.coo.uk> contains these words:
>
>
>> > Can't be - they've all got things sticking out of the tops of their
>> > heads. Mine's glassy smooth and unadorned.
>
>> You could try skull implants - a cross between dentistry and body piercing.
>
>That'd upset the little man who lives inside my head. At the moment he's
>busy winding all my hair in from my scalp and shoving it out of my ears
>and nostrils.

That's incredible! Absolutely *everyone* will want one of those for
Christmas. You'll be a trillionaire. What about a concrete dome island
in Polynesia?

Guy King

unread,
May 5, 2006, 6:35:21 AM5/5/06
to
The message <ge6m52t2nktp91198...@4ax.com>

from Mike Halmarack <...> contains these words:

> >> You could try skull implants - a cross between dentistry and body


> >> piercing.
> >
> >That'd upset the little man who lives inside my head. At the moment he's
> >busy winding all my hair in from my scalp and shoving it out of my ears
> >and nostrils.

> That's incredible! Absolutely *everyone* will want one of those for
> Christmas.

I suspect many of the males (and possibly a few of the females) who read
uk.d-i-y already have one.

Mike Halmarack

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May 5, 2006, 8:50:29 AM5/5/06
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On Fri, 5 May 2006 11:35:21 +0100, Guy King <guy....@zetnet.co.uk>
wrote:

>The message <ge6m52t2nktp91198...@4ax.com>


>from Mike Halmarack <...> contains these words:
>
>> >> You could try skull implants - a cross between dentistry and body
>> >> piercing.
>> >
>> >That'd upset the little man who lives inside my head. At the moment he's
>> >busy winding all my hair in from my scalp and shoving it out of my ears
>> >and nostrils.
>
>> That's incredible! Absolutely *everyone* will want one of those for
>> Christmas.
>
>I suspect many of the males (and possibly a few of the females) who read
>uk.d-i-y already have one.

Well, yes, this years model.

meow...@care2.com

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May 5, 2006, 3:32:49 PM5/5/06
to

Maybe dig the moulds as holes in the ground, adding a bit extra depth
to allow for crud, and leave until the lava flows.

Of course youre buildings would not then be in the most desirable
location!

The other natural house builder is coral. Submerge a thin ss frame,
leave it 50 years for coral to convert it into a solid coral house and
winch out. Nature's builders are so slow though, no wonder they find it
hard getting employment.


NT

Ian Stirling

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May 6, 2006, 6:44:15 AM5/6/06
to
meow...@care2.com wrote:
<snip>

> The other natural house builder is coral. Submerge a thin ss frame,
> leave it 50 years for coral to convert it into a solid coral house and
> winch out. Nature's builders are so slow though, no wonder they find it
> hard getting employment.

There are many schemes to grow your own home in SF;
'house seeds' - plant it, and it grows you a house using
nanotechnology and solar power in a few days, using local resources.
Specially trained plants, which you live inside, and digest human
waste, while providing food.
Bioengineered organisms, like coral, which you just train up a
framework, and water every so often, and keep trimming where you want
windows...

The fundamental problem with these approaches in real life is that it's
slow, given even fairly afvanced biotech.
Getting some sort of hut that'll keep the rain out most of the time, you
could use something very fast growing, though you need a nutrient
transfer system so that all sides grow as easily.

To get it to grow so that it can take 100MPH winds, and 3cm hail, is
gonna be much slower, as it's gotta be 'woodier'.

Then there is the 'trained monkey' approach, which a number of building
firms already seem to be trialing.

Owain

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May 6, 2006, 9:05:15 AM5/6/06
to
Ian Stirling wrote:
>>The other natural house builder is coral. Submerge a thin ss frame,
>>leave it 50 years for coral to convert it into a solid coral house and
>>winch out. Nature's builders are so slow though, no wonder they find it
>>hard getting employment.

Plan young for retirement ...

> There are many schemes to grow your own home in SF;

San Francisco? ... oh no, Sci-Fi

> Then there is the 'trained monkey' approach, which a number of building
> firms already seem to be trialing.

More expensive than the untrained monkeys used heretofore, but perhaps
higher productivity will compensate.

Owain

meow...@care2.com

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May 6, 2006, 6:31:06 PM5/6/06
to
Ian Stirling wrote:
> meow...@care2.com wrote:
> <snip>

> > The other natural house builder is coral. Submerge a thin ss frame,
> > leave it 50 years for coral to convert it into a solid coral house and
> > winch out. Nature's builders are so slow though, no wonder they find it
> > hard getting employment.

> There are many schemes to grow your own home in SF;
> 'house seeds' - plant it, and it grows you a house using
> nanotechnology and solar power in a few days, using local resources.
> Specially trained plants, which you live inside, and digest human
> waste, while providing food.
> Bioengineered organisms, like coral, which you just train up a
> framework, and water every so often, and keep trimming where you want
> windows...
>
> The fundamental problem with these approaches in real life is that it's
> slow, given even fairly afvanced biotech.

I guess it has to be lava then, build a whole housing estate in a day!

Might prove tough finding tenants tho. Then again on building day you
get lots of people conveniently made homeless.


> Getting some sort of hut that'll keep the rain out most of the time, you
> could use something very fast growing, though you need a nutrient
> transfer system so that all sides grow as easily.
>
> To get it to grow so that it can take 100MPH winds, and 3cm hail, is
> gonna be much slower, as it's gotta be 'woodier'.

If it were cheap enough, and it would really have to be cheap, some
kind of self build system that took 3 years would have its place. The
gross reduction in needed capital is what might make it workable. Say I
have 10 or 20k capital, no way can i build a house the today way. But
maybe I could plant a load of hedges on frames and leave them 3 years.
The frames would be sheathed in plastic film arranged like slates, so
the plant could grow through it easily, and it would keep rain out of
the gaps, and dump rain straight onto the plant roots. Now like this
the only capital needed is enough for some frames and seeds, plus the
money to fit out one house. Selling that provides capital for 2 more,
etc.

Plus it could see use for self build extensions, sheds and so on. Lots
of folk wouild like extensions and theres no rush but also no money.
Also could be used for the higher risk build projects, since the amount
risked is tiny.


> Then there is the 'trained monkey' approach, which a number of building
> firms already seem to be trialing.

Yes. Would be nice to see it happen in reality.


I once wondered if you could build walls out of plastic rubbish using a
movable piece consisting of 3 side walls and a glass top. The idea is
you put it on top of the wall, use it as your plastic recycling bin,
and solar heat melts the plastic to the wall. When full, move it along,
and in the end youve got a solid plastic walled structure for no more
cost or hassle than using a dustbin.

The pitfall is plasticisers. Repeatedly melting thermoplastics
evaporates plasticiser. Temp control could be achieved with a little
very basic electronics. It only needs to reach enough temp to melt some
of the plastics.


NT

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