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Re: GSBN:Moisture research



Rikki wrote:
This is interesting because of the ability of
the clay to draw the water out of the bales.

Is there anyone doing testing about that? The ability of clay or lime to
DRY
OUT wet bales?

Rikki,
I believe that the research you are interested in has to do with testing material's ability to absorb and release moisture from the surrounding environment. Tim Padfield did such testing for his PhD thesis:

<a  target="_blank" href="http://www.padfield.org/tim/cfys/phd/phd-indx.php";>http://www.padfield.org/tim/cfys/phd/phd-indx.php</a>

pages: 63-91


He calls this property humidity buffering capacity. Page 91 shows a graphic summary for materials like clay, lime, wood, wool, etc.. I found all Padfields articles very interesting. He gives among others good basic overview on humidity meters:

<a  target="_blank" href="http://www.padfield.org/tim/cfys/datalog/datlog4.php";>http://www.padfield.org/tim/cfys/datalog/datlog4.php</a>

and very importantly he gives a manual on how to calibrate them:

<a  target="_blank" href="http://www.padfield.org/tim/cfys/satslt/satsalt.php";>http://www.padfield.org/tim/cfys/satslt/satsalt.php</a>



I'm planning to finish the straw bale/moisture research in autumn 2006, so there is plenty of time for you to think about the answers to the QUESTIONNAIRE which is downloadable at: <a target="_blank" href="http://www.jakubwihan.com/pdf/SB_Moisture_Questionnaire.doc";>http://www.jakubwihan.com/pdf/SB_Moisture_Questionnaire.doc</a>

Rikki, did the people who did the test on the plastered rotten straw bale make any documentatioon? Is it available?

Best,

Kuba








----- Original Message ----- From: "Rikki Nitzkin" rikkinitzkin@...
To: "'GSBN'" GSBN@...
Sent: Tuesday, May 02, 2006 10:22 AM
Subject: RE: GSBN:Moisture research


There was a very interesting, if poorly documented experiment done in spain
about rotten bales.

They took extremely rotten, wet, moldy, mushroom sprouting bales and made
the best wall they could.

They then put a thick (about 10cm) layer of straw-clay plaster on top.  In
this hot (40&#xBC;c)sunny climate it took 4 MONTHS for the plaster to dry.
Eventually it did, and they opened a hole in the wall to find dry (if weak
and dusty!) straw behind it. This is interesting because of the ability of
the clay to draw the water out of the bales.

Is there anyone doing testing about that? The ability of clay or lime to DRY
OUT wet bales?

Rikki Nitzkin
Aul?s, Lleida, Espa?a
rikkinitzkin@...
(0034)657 33 51 62
www.casasdepaja.com (Red de Construcci?n con Balas de Paja)


-----Mensaje original-----
De: GSBN [<a  target="_blank" href="mailto:GSBN@...";>mailto:GSBN@...] En nombre de Jakub Wihan
Enviado el: mi?rcoles, 19 de abril de 2006 12:40
Para: GSBN
Asunto: Re: GSBN:Moisture research

Dear Martin, Dirk and others



Thank you very much for your support. The responses I have gotten in the
last few hours are so encouraging and it goes on...



During my research, I found a number of studies that have explored the
microorganism population on straw over time either in laboratories or in
the
field. The  classic paper: "How Straw Decomposes"  by Summers, Blunk and
Jenkins focuses on the quantity of population on rice straw during
decomposition in a low moisture content environment in sealed containers.



Does anyone know if a similar study (quantity development of
microorganisms
over time) has ever been done on straw directly in a wall?



There are many practices developed by experience that help to prevent
moisture failure of a straw bale construction (the questionnaires I
received
so far summarize them nicely). One of them is impeccable, but "breathable"
plaster. I feel that  simple research over a longer period of time on
development of microorganism quantity on straw in walls covered with
different plasters could lead to potential improvements in  straw bale
technology. The influence of plaster on microorganism growth could be
quite
complex - for example the moist earth plaster swells up air tight,
preventing oxygen availability for decomposition, lime is natural
microorganism killer, etc.



GrAT, The Center for Appropriate Technology at the Vienna University of
Technology - is carrying out similar long term research. I'm trying to
contact them, but they haven't  responded. It seems that the results
aren't
available yet.







And please, to those who haven't done so yet, don't forget to fill out the
questionnaire.



Thank you.



Very best wishes



Kuba


----- Original Message -----
From: "Dirk Scharmer- FSB" ds@...
To: "'GSBN'" GSBN@...
Sent: Wednesday, April 19, 2006 10:14 AM
Subject: RE: GSBN:Moisture research


> Dear Kuba,
> I'm happy that you do this work. We're doing some moisture research too.
>
> - Moisture/ temperature monitoring on 4 houses - one is being monitored
> since November, 2004.
> - Dynamic moisture transport simulation with WUFI
> - Mold analyzing of embedded straw
>
> The goal is to find the best prevention against moisture failure of a
> straw
> bale construction and to get this in a buidling code.
>
> In the next weeks we'll start a comprehensive research project with more
> simulations, monitoring and analyzing. Our work and your work would fit
> together perfectly to describe the complex mold problem of straw bales.
> Your
> way to come more from the practical side may be the more significant one
> for
> the building site. The way of simulating and mold analyzing for me seems
> to
> be a good way to fit the requirements of the german building
authorities.
> Our first general approval for straw bales as an insulation material is
> mainly based on simulations. Unfortunately we were not able to prove the
> mold resistance of directly earth plastered straw bales, but we hope to
do
> this with the upcoming research.
> We are working together with the Fraunhofer Institut fuer Bauphysik,
> www.hoki.ibp.fraunhofer.de.
>
> Let's get in contact!
>
> Perhabs you would like to join our anual straw bale meeting in august,
> 18th-20th. There are some other international guests.
>
> But anyway, I think we'll meet not later than ISBBC in Lakefield, do we?
>
> You'll get my filled out questionaire immediately.
>
> Greetings,
>
> Dirk
>
> -----------------------------------------------
> Fachverband Strohballenbau Deutschland e.V.
> Auf der Ruebekuhle 10
> D- 21335 Lueneburg
> Tel. 00 49 4131- 727804
> Fax. 00 49 4131- 727805
> Internet: www.fasba.de
> Email: ds@...
>
> ----
> GSBN is an invitation-only forum of key individuals and representatives
of
> regional straw construction organizations. The costs of operating this
> list are underwritten by The Last Straw Journal in exchange for use of
the
> GSBN as an advisory board and technical editing arm.
>
> For instructions on joining, leaving, or otherwise using the GSBN list,
> send email to GSBN@...HELP in the SUBJECT line.
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>
>

----
GSBN is an invitation-only forum of key individuals and representatives of
regional straw construction organizations. The costs of operating this
list are underwritten by The Last Straw Journal in exchange for use of the
GSBN as an advisory board and technical editing arm.

For instructions on joining, leaving, or otherwise using the GSBN list,
send email to GSBN@...HELP in the SUBJECT line.
----



----
GSBN is an invitation-only forum of key individuals and representatives of
regional straw construction organizations. The costs of operating this list
are underwritten by The Last Straw Journal in exchange for use of the GSBN
as an advisory board and technical editing arm.

For instructions on joining, leaving, or otherwise using the GSBN list, send
email to GSBN@...HELP in the SUBJECT line.
----


----
GSBN is an invitation-only forum of key individuals and representatives of regional straw construction organizations. The costs of operating this list are underwritten by The Last Straw Journal in exchange for use of the GSBN as an advisory board and technical editing arm.

For instructions on joining, leaving, or otherwise using the GSBN list, send email to GSBN@...HELP in the SUBJECT line.
----