[GSBN] building in Haiti

[kim thompson]

Hello all,

We have been doing various lime over earth experiments here in the  
Maritimes over the last six years or so.
One system that has had good results in this "very hard on any kind  
of building" climate of Nova Scotia is
to add a small i.e. 5% amount of lime to the final earth layer then  
leave this coat rough (or as with a scratch coat)
to give a mechanical bond for the lime and sand plaster (1-2 coats).  
My theory is that adding some lime to the clay makes it
more "compatible" for the subsequent lime layers, but this is purely  
conjecture. Would love to do more serious testing on this.

Indeed we have found that just adding the lime putty to the clay does  
amazing things to making it more water resistant. Hose tests
and 6 winters confirm this. Getting this recipe right is likely  
relative to type of clay etc. so maybe challenging to standardize, or  
it may
be that it is more forgiving than I think.

One comment on the opportunity to showcase this project and the  
importance (or not) of it being perfect. If the interpretive  and  
educational
aspects of the build are very clear from the outset that it is a  
prototype and that the climate and resources present new  
opportunities that are being explored then the project takes on much  
bigger significance. Perhaps the best case scenario is to do one wall  
with a rainscreen system, one with LoE, one with lime mixed with  
earth and one lime only (aka Amazon Nails). Hose tests can predict a  
fair bit, but one season of weather on a wall that is well roofed and  
footed can be repaired with which ever seems to work best.

Another thin wall, fast and "secure" system is to recycle chain link,  
or similar (which maybe found in the debris) and use that as a  
"wattle" attached to bamboo (or other) posts. The daub is the usual  
fibre rich mud with a  lime/earth and then a lime/sand or lime wash  
finish.

A few thoughts for the mix.


>
>
> On 2/03/2011, at 9:11 AM, Bruce King wrote:
>
>>
>> Hi, folks, we've got a bit of a debate going as to what  
>> constitutes a security barrier, which is fine by me, but I for one  
>> would really like to hear more about lime plasters over earth.
>>
>> Answers so far, as well as my experience, suggest that LoE (lime  
>> over earth) systems work very well if, and only if, you have a  
>> familiar and consistent mix of lime, clay, straw, etc.  All of the  
>> ingredients are finicky (you can't just substitute one lime for  
>> another, or one clay for another), all depend on careful  
>> workmanship (application, curing, scratching, etc.), none are for  
>> newbies.
>>
>> In Haiti, though we will have one or two pros running things  
>> (maybe some of y'all), we will be working with a Haitian crew of  
>> unknown skill, using clay, sand and lime whose properties and  
>> behavior are unknown.
>>
>> Are we crazy to even contemplate a LoE system?  Remember, this  
>> will be a very public house seen and scrutinized by a lot of  
>> people and organizations.  There's no room for screwups or  
>> excuses.  If it cracks, or delaminates, or in some other way  
>> fails, the whole project looks bad.
>>
>> We'd rather look good.  Any further advice would be much appreciated.
>>
>> PS to Graeme North:  thanks for the tips, I know that cintoflex is  
>> good stuff, and may even be available in Haiti.  And prayers for  
>> New Zealand, you guys got hit hard.  Prayers for Haiti, too;  a  
>> year after their earthquake, the city and country still look like  
>> it happened a week ago, there's that little recovery.  Poverty,  
>> dysfunctional government, and a lack of infrastructure is a fairly  
>> deadly combination that even the most noble and intelligent people  
>> (as are Haitians) can barely overcome.
>>
>> Thanks,
>>
>> Bruce King, PE
>> Director of EBNet
>> Ecological Building Network
>> the art and science of building well
>> bruce at ecobuildnetwork.org
>> PO Box 6397
>> San Rafael, CA 94903 USA
>> (415) 987-7271
>> follow us on Twitter: @EBNetwork
>>
>> On Mar 1, 2011, at 11:43 AM, Andy Horn wrote:
>>
>>> Hi Martin
>>> I agree it is more about securing the windows and doors.
>>>
>>> Plaster aside, for anyone who has not yet tried – but getting  
>>> through a wall of straw is no mean feat.
>>>
>>> I once got called in to look at saving storm wrecked load bearing  
>>> SB after the guys building had left for a long weekend without  
>>> covering up ……so I helped with cutting out chunks of un-plastered  
>>> wall, so as to retrofit in sets of load bearing timber posts.  
>>> Armed with a chainsaw you would be surprised at just how  
>>> difficult it was.
>>>
>>>
>>> Andy Horn
>>>
>>>
>>>
>>>
>>> From: GSBN-bounces at greenbuilder.com [mailto:GSBN- 
>>> bounces at greenbuilder.com] On Behalf Of martin hammer
>>> Sent: 01 March 2011 05:54 AM
>>> To: (private, with public archives) Global Straw Building Network
>>> Subject: Re: [GSBN] building in Haiti
>>>
>>> Bruce, all,
>>>
>>> Although on the EBNet Haiti team (in addition to the BWB SB Haiti  
>>> team), I'll jump into the GSBN forum with a couple thoughts on  
>>> the plaster and the security issue.
>>>
>>> The security concern will be greater in some locations than  
>>> others.  Generally, the more urban the greater the concern.  It  
>>> seems obvious that both in perception and as a physical obstacle,  
>>> mesh reinforced cement plaster would be the most secure plaster,  
>>> and I’ll say probably secure enough.  (Notwithstanding Derek’s  
>>> proposed method of breaking and entering, that still takes time,  
>>> effort, makes noise, etc, and thus is a deterrent).  In some  
>>> cases clay, or lime plaster may not be enough, in other cases it  
>>> will.  Installing a second plaster on the inside face of the  
>>> bamboo framing would provide additional security (real and  
>>> perceived).
>>>
>>> For the Home Expo building I suggest installing a cement plaster  
>>> (with up to 50% lime if you can get your hands on it) on half the  
>>> building, and a clay plaster with a durable finish on the other  
>>> half.  With and without a second plaster on the interior.  Let  
>>> people see how they both feel, look, and sound, and allow them to  
>>> decide which would work for their circumstance.
>>>
>>> Cordaid, a Dutch organization, built a prototype wood-framed  
>>> house in Leogane, Haiti with no less than 7 enclosure-finish  
>>> systems.  (I can send photos, if you haven't seen it already.)  I  
>>> think it goes too far to the point of being chaotic/confusing.   
>>> But a couple variations in one prototype building seems valid to  
>>> me.  Looking at opposite corners you might only see one finish at  
>>> a time.
>>>
>>> In terms of security, doors and windows (shutters?) will probably  
>>> be a greater point of vulnerability than the wall enclosure  
>>> system.  I would show how that can be addressed on at least one  
>>> opening.
>>>
>>> Also, although security can be a serious issue in parts of Haiti  
>>> (and other places in the world!), there of course is much more to  
>>> consider about this building . . .
>>>
>>> Martin Hammer
>>>
>
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Kim Thompson
Straw Bale Projects
2699 Northwood Terrace
Halifax, Nova Scotia B3K 3S9
tel. 902-453-2429
e mail: shipharbour at ns.sympatico.ca
www.naturalbuilding.ca

"Tradition and modernity are merely two sides of the same coin - and  
must be dealt with simultaneously. Building cannot be a rigid dogma,  
but a living, organic, ecological project. It is about continuity,  
based on memory, common sense and experience and is the foundation of  
invention."   Hasan Uddin Khan




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