[Cob] cob greenhouse question

[Malcolm Schluenderfritz]

Hello John,

Thanks again. One more question: could the buttresses be straw bale walls?
I am thinking that the buttresses protruding from the back wall could be
used as a chicken coop, which would benefit from heat from the cob wall,
and insulate the greenhouse. I would already have three walls and the roof
overhang.

Yours,
Malcolm

On Wed, Sep 23, 2015 at 11:11 PM, john fordice <otherfish at comcast.net>
wrote:

> Hi Malcom,
> Yes, the freestanding ends of your walls and midpoint of the long back
> wall should still be buttressed.  I’d suggest putting the buttresses on the
> outside surface of the walls & thus leave the rtransparent greenhouse walls
> fully open to sunlight.
> Small p[eces of urbanite should be ok, just don’t make them any bigger
> than 2 - 3 “.
> john
>
> On Sep 23, 2015, at 3:14 PM, Malcolm Schluenderfritz <
> mschluenderfritz at gmail.com> wrote:
>
> Hello John,
>
> I modified the design. Now the tallest cob wall will be 6 feet. Do I still
> need buttresses?
>
> I will leave out the urbanite chunks then. Would small pieces of rubble
> less then two inches across be OK? I was wondering if they would act like
> large gravel.
>
> Thanks for your help.
>
> Malcolm
>
> On Sat, Sep 19, 2015 at 10:18 PM, john fordice <otherfish at comcast.net>
> wrote:
>
>> Malcome,
>> A few suggestions relating to the cob:
>> 1. Buttress the open ends of your rear & left end walls.  Make the
>> buttress’s 3 or 4’ long at the stem wall & zero at the wall top.  Add an
>> intermediate buttress at the midpoint of the rear wall.
>> 2. Batter your walls to 12” thick at the top & 18” at the stem wall.
>> 3. Do not put pieces of urbanite in the cob …… bad practice !
>>
>> This is relative to the cob only ……… the framing of the transparent
>> materials support is another story …… sounds like the loads of the wood &
>> plastic roof / walls will be minimal, so as long as you don’t have heavy
>> concentrated loads either embed your rafters in the cob or add a top plate
>> with deadmen in the wall.   Assuming you know how to make competent cob &
>> build correctly ……… if not, get advice of an experienced cobber.
>> john
>>
>> > On Sep 19, 2015, at 9:51 AM, Malcolm Schluenderfritz <
>> mschluenderfritz at gmail.com> wrote:
>> >
>> > ---------- Forwarded message ----------
>> > From: Malcolm Schluenderfritz <mschluenderfritz at gmail.com>
>> > Date: Fri, Sep 18, 2015 at 8:40 PM
>> > Subject: Re: [Cob] cob greenhouse question
>> > To: Howard Switzer <howard at earthandstraw.com>
>> >
>> >
>> > Hello Howard,
>> >
>> > Thanks for the advice.
>> >
>> > I will try to post a plan soon.
>> >
>> > I am stuck with the 18" base because the foundation is already build. I
>> > agree that it seems something is needed at the North East corner.
>> >
>> > The concrete is to use it up and to speed drying on the wall. (An idea
>> from
>> > "The Hand Sculpted House." ) I got huge loads of broken concrete dumped
>> for
>> > the foundation and for retaining walls on other parts of the site. These
>> > are pieces that are fairly good but not quite square enough for those
>> uses.
>> > Spaced widely (so that they do not form problematic joints) in the core
>> of
>> > the wall, it seems that they will allow me to use less cob, which not
>> only
>> > means faster drying, but also less cob mixing and less purchased sand
>> use.
>> >
>> > I would think that if cob is strong enough to arch over small niches, it
>> > would be strong enough to take a few pieces of concrete inside the wall.
>> > But correct me if I am wrong.
>> >
>> >
>> >
>> > On Fri, Sep 18, 2015 at 8:29 PM, Howard Switzer <
>> howard at earthandstraw.com>
>> > wrote:
>> >
>> >> I know John will take good care of you, (do post your plan if you can)
>> but
>> >> basically you got a 16 foot wall braced on one end, right, so sounds
>> like
>> >> you need to brace the other end somehow. Now I expect there will be an
>> east
>> >> wall so you might consider bracing it in such a way as it could serve
>> to
>> >> buttress the end of the wall and you might want to embed some anchors
>> in
>> >> the cob for attaching that bracing wall....or you could just do a cob
>> >> buttress off the end of the wall in the other direction, which is
>> probably
>> >> the better option, just guessing. You might also want to consider
>> battering
>> >> the wall a bit, wider (20") at the bottom than the top (16"), right?
>> Might
>> >> add some more stability. What are the concrete pieces doing in the
>> middle
>> >> of it?  Just trying to get rid of it or something?
>> >>
>> >>
>> >>
>> >> On Fri, Sep 18, 2015 at 2:31 PM, Malcolm Schluenderfritz <
>> >> mschluenderfritz at gmail.com> wrote:
>> >>
>> >>> I am building a small greenhouse, 16 feet by 8 feet, and 8 feet tall.
>> The
>> >>> North and West walls will be cob, and about 18 inches thick. I will be
>> >>> inserting some pieces of concrete as we go, in the center of the
>> wall. The
>> >>> walls are straight, not curved.
>> >>> Do I need to add buttresses to this wall to keep it up, or is it thick
>> >>> enough? The North and West walls already form a corner, so they
>> provide at
>> >>> least a little Lateral support to each other.
>> >>> _______________________________________________
>> >>> Coblist mailing list
>> >>> Coblist at deatech.com
>> >>> http://www.deatech.com/mailman/listinfo/coblist
>> >>>
>> >>
>> >>
>> >>
>> >> --
>> >> Howard Switzer - Architect
>> >> 668 Hurricane Creek Road
>> >> Linden, TN 37096
>> >> 931 589 6513
>> >> www.earthandstraw.com
>> >>
>> >> “You never change things by fighting the existing reality.
>> >> To change something, build a new model that makes the existing model
>> >> obsolete.”
>> >> ― Richard Buckminster Fuller
>> >> <
>> http://www.goodreads.com/author/show/165737.Richard_Buckminster_Fuller>
>> >>
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> > --
>> > Malcolm Schluenderfritz
>> > Secretary,
>> >
>> > The Saint Isidore Society,
>> > saintisidoresociety.wordpress.com
>> > _______________________________________________
>> > Coblist mailing list
>> > Coblist at deatech.com
>> > http://www.deatech.com/mailman/listinfo/coblist
>>
>>
>
>
> --
> Malcolm Schluenderfritz
> Secretary,
>
> The Saint Isidore Society,
> saintisidoresociety.wordpress.com
>
>
>


-- 
Malcolm Schluenderfritz
Secretary,

The Saint Isidore Society,
saintisidoresociety.wordpress.com