[GSBN] building in Haiti

Wed Mar 2 12:03:21 UTC 2011

Hi all,
I just want to second Derek's concerns/thoughts. I've seen lime delaminating from earth plaster bases in China (not one of my buildings, thankfully) and it's a pretty dramatic failure. You wouldn't want people to see a plaster failure and throw out the whole building system.

Given the wide fluctuations in moisture in the Haitian climate combined with the lack of local experience/knowledge of LoE and high scrutiny for a public project, I'd stick with all earth plaster with a lime wash (earth plaster could have lime putty component) OR a lime plaster OR a lime/cement plaster. Or all of these types of plaster could be tested on a single building as Kim was suggesting, to see how they fare.  

Though I'm quite experimental on my own buildings, I tend to be more conservative with public development projects. I would also look for a good local plaster expert in Haiti and let him/her take the lead on developing the right plaster approaches. 

Take care and good luck,

Kelly

On Mar 2, 2011, at 12:23 AM, Derek Roff wrote:

> I think you have laid out the odds against successful use of lime over earth (LoE) plaster pretty well.  There are too many unknowns.  I'll add a few of more reasons why I would not choose lime over earth in this, and most, situations.  Failures, when they happen, are frequently fairly dramatic, with large sections of plaster delaminating.  In the case of failure, it is not obvious how to make a repair, or if a repair is possible, without removing all of the plaster, and replacing the lime with another material.  Failures must be addressed with even more expertise, analysis, and testing than was available during initial construction.  That expertise is unlikely to be available.  Failures often come a year or more after application of the plaster, meaning that the team of people involved with the building and plastering is likely to be dispersed.  At the moment of failure, finding anyone with significant LoE expertise for analysis and repair may be difficult or impossible.
> 
> Lime and earth react differently to moisture changes, so LoE plaster can do fine for a while, and then fail when conditions change more extremely or more rapidly than usual.  In a location with variable and dramatic rain and moisture cycles, it's even harder to predict whether a given plaster job will stand the test of time, or is just about to fail during the next hurricane.  Finally, as I understand it, the people who will be building and using these buildings don't have a tradition and experience with LoE systems, which makes it very difficult for them to do effective maintenance, address problems, and make effective repairs.
> 
> There is a tradition of LoE in the Caribbean, coming out of both French and Spanish colonial periods.  However, almost all of the knowledge and experience has been lost in the popular context, and I think there are too many challenges to try and regain the skills quickly.
> 
> Derelict
> 
> Derek Roff
> Language Learning Center
> Ortega Hall 129, MSC03-2100
> University of New Mexico
> Albuquerque, NM 87131-0001
> 505/277-7368, fax 505/277-3885
> Internet: derek at unm.edu
> 
> 
> 
> --On Tuesday, March 1, 2011 12:11 PM -0800 Bruce King <bruce at ecobuildnetwork.org> 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
> 
> 
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Kelly Lerner, Architect
One World Design Architecture
509-838-8812
www.one-world-design.com

Have you read Natural Remodeling for the Not-So-Green House? Available in Bookstores across the Universe. 
www.naturalremodeling.com

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