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GSBN: Digest for 10/8/07



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-> Re: GSBN:Re: Lime plaster problems
     by Athena & Bill Steen absteen@...
-> Re: GSBN:Re: Lime plaster problems
     by Athena & Bill Steen absteen@...
-> Re: GSBN:Re: Lime plaster problems
     by Athena & Bill Steen absteen@...
-> Re: GSBN:Re: Lime plaster problems
     by jeff@...
-> Plaster on Framed Walls
     by jswearingen@...
-> Re: GSBN:Plaster on Framed Walls
     by cmagwood@...


----------------------------------------------------------------------

Date: 8 Oct 2007 09:06:50 -0500
From: Athena & Bill Steen absteen@...
Subject: Re: GSBN:Re: Lime plaster problems

Dear Judy,
The answer is simple.  You and Matts have accrued such a huge amount
of good straw bale karma that the gods are simply smiling on you.  I
mean isn't that enough to ensure success on whatever you touch.

The other reason is that for some combo of the variables that I
mentioned you got it right.  I think it's impt to remember that I
didn't say "never." Only that it can be really difficult for all
those pieces to come together.

The other thing I didn't include in that earlier email was how
difficult it can be to cure the lime plaster properly.  As one
English lime expert put it, "when it comes to lime plaster there is
nothing in the European experience that comes even close to
replicating the conditions found in the southwestern US.  Even more
proof that the SB gods smile on you.

B...
On Oct 7, 2007, at 5:12 PM, Judyknox42@...:

> Matts and I have had great success with lime plaster over clay
> plasters,
> particularly in the bale wrap project next door which is in its 7th
> year, exposed
> to the west sun and weather, and doing just fine.  Now I'm going to
> have to
> put my head together with him and try to figure out why it's worked
> so well.
> Plaster on...(not to be confused with let's get plastered)
> Judy
>
> Judy Knox and Matts Myhrman
> Out On Bale
> 1037 E. Linden St.
> Tucson, Az  85719
> 520-622-6896
> judyknox42@...
> mattsmyhrman@...
>
> Each of us can and must champion the evolutionary breakthroughs
> necessary to
> sustain all life.  The journey of a champion is difficult, AND our
> access to a
> joyful life.
> Judy Knox
>
>
> **************************************
>  
> 
>
>
> --- StripMime Report -- processed MIME parts ---
> multipart/alternative
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>

Athena & Bill Steen
The Canelo Project
HC1 Box 324
Canelo/Elgin, AZ 85611
absteen@...
www.caneloproject.com




----------------------------------------------------------------------

Date: 8 Oct 2007 09:09:55 -0500
From: Athena & Bill Steen absteen@...
Subject: Re: GSBN:Re: Lime plaster problems

Franko,
I think a major plus in your area is the calcium component in the  
caliche soils.  So therefore we have a chemical connection going on  
beside the mechanical.  And that is what is basically lacking with  
most soils.  One way to increase the possibility of a better chemical  
bond is to use marble aggregate instead of quartz sand.

B...
On Oct 7, 2007, at 2:50 PM, thangmaker@...:

> Thank you, Bill.  I have had good results and no problems to date  
> putting lime over earthen plaster made with our native caliche  
> clay.  We have done what Bill
>
>
> suggests:  scratching the surface well and letting the earthen  
> plaster dry completely.  For those unfamiliar with caliche it  
> occurs in the same soil as limestone.
>
>
> It is the same basic material as lime (calcium carbonate) but less  
> dense and not well bonded to itself...flakey if you will.    
> Occasionally clay is found with this
>
>
> material and is the best clay I have seen in terms of PI index (low  
> expansion and contraction).   This is the clay I wanted to use for  
> the fire test last year in San Antonio but as Matts pointed out it  
> would not perform well in a hot fire.   I am guessing the material  
> is similar enough to lime plaster that it both bonds well to it and  
> their rate of movment and reaction to moisture is similar.
>
>
>
>
>
> Cheers
>
>
> Frank Meyer
>
>
> PS we are hosting a Natural Building Colloquim later this month  
> www.naturalbuildingtexas.org and have a great caliche clay pit on  
> site.
>
>
> -----Original Message-----
>
> From: Athena & Bill Steen
>
> To: GSBN
>
> Sent: Sun, Oct 7 12:11 PM
>
> Subject: Re: GSBN:Re: Lime plaster problems
>
>
>
>
>
> I'll plead busy as well and before I made any comments I wanted to  
> make sure they would be somewhat thorough. There are a few things  
> that have become evident to me over the years when it comes to lime  
> over clay plaster. In mho I would have to say that results are  
> unpredictable and undependable. I'm not saying it can't or doesn't  
> work, but rather that outcomes vary widely. David Bainbridge  
> mentioned in his earlier post the Getty people in Los Angeles as a  
> resource. I've made it a point to talk with them every few years  
> about lime plaster and in particular their work with prickly pear  
> cactus gel. Anyhow in one of the last conversations we had they  
> told me that there was a growing sentiment amidst the conservation  
> community that the use of lime plaster over earth surfaces was not  
> such a good idea. They mentioned that although lime had better  
> permeability than cement and allowed the earth to dry better when  
> wet, it was still too different from an earthen substrate for it to  
> work dependably.
>
>
>
> My experience basically says the same thing. For me the whole issue  
> comes down to what type of earth plaster is underneath. Apparently  
> some are much better than others and just what all the variables  
> are I can't say. I think it will take some time to get a better  
> grasp on it. Clearly I would suggest that if the substrate has a  
> lot of clay there is a likely possibility that if water is absorbed  
> through the lime plaster and passed on to the earth substrate then  
> obviously the clay will expand and have a tendency to push the lime  
> plaster away therefore causing the two to separate. If the earth  
> plaster is weak then the connection will break down over time. So  
> in short I guess what I'm saying is that the earth plaster has to  
> be of a really good quality for any chance of success. It needs to  
> be strong and not have an overly high content of expansive clay.  
> Another very important piece is that the earthen plaster substrate  
> must be thoroughly dry as earth plasters shrink when drying. If  
> that process is not complete the earth will pull away from the lime  
> plaster and leave it hanging in the air. And as others have pointed  
> out the surface needs to be extremely well keyed for the lime to  
> adhere. I don't think you can under-do that aspect. Additional  
> measures like that of placing sharp jagged stones in the plaster  
> would also help such as the practice of "rahuela" used in Mexico  
> where stones are placed in the mortar joint between adobes.
>
>
>
> I think it was David that also mentioned the Japanesete We have  
> worked closely with a pair of Japanese plasterers over recent years  
> and it is important to note that the Japanese approach relies  
> heavily on use of a glue when mixing what they call "Shikkui."  
> Traditionally rice flour was used but was replaced with seaweed gel  
> during a time of food shortages. In general I would say that their  
> plastering practices are far more meticulous than anything I've  
> seen in this part of the world and in the words of the best  
> plasterer from there that I can think of, "there is great  
> difficulty in the connection between the two coats and at best it  
> does not last for a very long time."
>
>
>
> Having said all this I will say that my comments apply primarily to  
> exterior finishes and I've not yet experienced any problems with  
> interior or protected locations. But I should add that we also  
> typically include a percentage of some glue material in the lime  
> plaster.
>
>
>
> John Glassford suggested the use of lime/clay as an alternative and  
> I think that it can be a very good one. Much here depends upon the  
> reaction between the clay soil and the lime. Over the years I've  
> watched varying reactions, some soils produce exceptional results,  
> others marginal. I recently cornered Harry Francis who once worked  
> for the American Lime Association while we happened to be together  
> recently in Washington DC. I told him that the using pH as an  
> indicator of the right type of mix was not proving true all of the  
> time. Like he always does Harry went home and searched his  
> extensive resources and just emailed me a paper that addresses some  
> of those variables particularly soils with high levels of potassium  
> and sodium carbonates. I haven't had time to really absorb the  
> content, but if any of you want a copy I would be happy to forward it.
>
>
>
> I've already said more than I had intended, but to sum it up I  
> would not suggest that we recommend the use of lime plaster over  
> earthen substrates as a general practice. I would suggest that it  
> be adopted only after some testing and experimentation has been  
> done and with a warning that the results are always guaranteed.
>
>
>
> Bill
>
> On Oct 7, 2007, at 7:10 AM, Rikki Nitzkin wrote:
>
>
>
>> Sorry to chime in so late...been busy. Its just that I haven't  
>> seen > anywhere
>
>> that in the responses to remind Andy that it is very important to  
>> > wet down
>
>> as well as scratch the base layer of plaster before applying a new  
>> > coat, and
>
>> if the material is different (lime on clay in this case) really  
>> rub > the
>
>> first bit in so it binds well.
>
>>
>
>> Hope your problem has been solved.
>
>>
>
>> Rikki Nitzkin
>
>> Aulas, Lleida, Espana
>
>> rikkinitzkin@...
>
>> (0034)657 33 51 62
>
>> www.casasdepaja.com (Red de Construccion con Balas de Paja)
>
>>
>
>>
>
>>> -----Mensaje original-----
>
>>> De: GSBN [<a  target="_blank" href="mailto:GSBN@...";>mailto:GSBN@...] En nombre de Brian  
>>> >> Hodge -
>
>>> Anvill
>
>>> Enviado el: jueves, 27 de septiembre de 2007 22:20
>
>>> Para: 'GSBN'
>
>>> Asunto: RE: GSBN:Re: Lime plaster problems
>
>>>
>
>>> Hi Andy,
>
>>> I agree with John. We have been doing a very similar thing for >>  
>>> about 5
>
>>> years and have not found it necessary to add the lime putty top  
>>> >> coat. We
>
>>> have even done it without chaff with a great deal of success.
>
>>>
>
>>> Regards
>
>>>
>
>>> Brian
>
>>>
>
>>> Anvil Straw
>
>>>
>
>>> -----Original Message-----
>
>>> From: GSBN [<a  target="_blank" href="mailto:GSBN@...";>mailto:GSBN@...] On Behalf Of John
>
>>> Glassford
>
>>> Sent: Thursday, 27 September 2007 7:53 AM
>
>>> To: GSBN
>
>>> Cc: Andy Horn
>
>>> Subject: Re: GSBN:Re: Lime plaster problems
>
>>>
>
>>>
>
>>> G ' day Andy
>
>>>
>
>>> My two rands worth mate.
>
>>>
>
>>> You will need to remove the lime coat and scratch up the earth as  
>>> >> others
>
>>> have said.
>
>>>
>
>>> I would then apply a mix of earth/lime/sand and chaff or chopped  
>>> >> straw.
>
>>>
>
>>> All depends on the clay content of your earth but I would look at
>
>>> something like this 3 parts soil 2 parts lime 3 parts sand 1 part  
>>> >> chaff.
>
>>> I use buckets for this mix. It works well and binds well with the
>
>>> earthen render. Then if you want you can apply a finish coat of lime
>
>>> render however I have not found that necessary in most cases >>  
>>> except for
>
>>> look.
>
>>>
>
>>> You can see a house we renedered with earth, then earth/lime/sand/ 
>>> >> chaff,
>
>>> then lime/sand, here:
>
>>>
>
>>> <a  target="_blank" href="http://glassford.com.au/Jumbo.htm";>http://glassford.com.au/Jumbo.htm</a>
>
>>>
>
>>> No delamination no cracks and it is nearly 6 years since we finished
>
>>> there.
>
>>>
>
>>> Was in Cape Town a few weeks ago but did not have time to see  
>>> much it
>
>>> was a Rotary trip with Hout Bay. We will be back next year for an
>
>>> extended visit, see you then.
>
>>>
>
>>> Kind regards
>
>>> The Straw Wolf
>
>>> Huff 'n' Puff Constructions
>
>>> <a  target="_blank" href="http://www.glassford.com.au/";>http://www.glassford.com.au/</a>
>
>>>
>
>>> 61 2 6927 6027
>
>>>
>
>>> Mount Kilimanjaro Climb 28/8/07 <a  target="_blank" href="http://www.coolamonrotary.com/kili/";>http://www.coolamonrotary.com/kili/</a>
>
>>> ----
>
>>> For instructions on joining, leaving, or otherwise using the GSBN  
>>> >> list,
>
>>> send email to GSBN@...HELP in the  
>>> SUBJECT >> line.
>
>>>
>
>>> ----
>
>>>
>
>>>
>
>>>
>
>>>
>
>>> ----
>
>>> For instructions on joining, leaving, or otherwise using the GSBN  
>>> >> list,
>
>>> send email to GSBN@...HELP in the  
>>> SUBJECT >> line.
>
>>> ----
>
>>
>
>> ----
>
>> For instructions on joining, leaving, or otherwise using the GSBN  
>> > list, send email to GSBN@...HELP in the  
>> > SUBJECT line.
>
>> ----
>
>>
>
>
>
> Athena &amp; Bill Steen
>
> The Canelo Project
>
> HC1 Box 324
>
> Canelo/Elgin, AZ 85611
>
> absteen@...
>
> www.caneloproject.com
>
>
>
> ----
>
> For instructions on joining, leaving, or otherwise using the GSBN  
> list, send email to GSBN@...HELP in the  
> SUBJECT line. ----
>
>
> ______________________________________________________________________ 
> __
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> SUBJECT line.
> ----
>

Athena &amp; Bill Steen
The Canelo Project
HC1 Box 324
Canelo/Elgin, AZ 85611
absteen@...
www.caneloproject.com




----------------------------------------------------------------------

Date: 8 Oct 2007 09:12:23 -0500
From: Athena &amp; Bill Steen absteen@...
Subject: Re: GSBN:Re: Lime plaster problems

Bruce,
No I didn't mean "never" guaranteed.  I have simply watched so many
new people to the SB world think that this combo was a simple
cakewalk and it just isn't.  It takes a lot of thought, diligence and
flat out good luck to make it work.

As for wetting the surface of the earth plaster I don't think that is
too much of a problem.  What is more of a problem is when the earth
plaster is dry on the surface and still wet 3/4 of an inch in.  That
is what is deceptive and can easily fool.

B...
On Oct 7, 2007, at 11:31 AM, Bruce King wrote:

>
> On Oct 7, 2007, at 9:00 AM, Athena &amp; Bill Steen wrote:
>
>>  . . . Another very important piece is that the earthen plaster
>> substrate must be thoroughly dry as earth plasters shrink when
>> drying.
>> If that process is not complete the earth will pull away from the
>> lime
>> plaster and leave it hanging in the air.
>
> Bill, thanks as always for a thoughtful and well-articulated post.
>
> The above excerpt makes me think that the case is even weaker than you
> say for lime over earth, in that you really don't want to apply a lime
> plaster to a bone dry earthen substrate.  The earth would suck the
> moisture prematurely out of the lime, wrecking or impeding a good
> cure.
>  But if you moisten the earth first, then you are applying lime to the
> substrate in its expanded state -- which happens anyway as bone-dry
> earth sucks moisture long before the lime sets.  Looks like a lose-
> lose
> proposition, or rather that you end up relying completely on glue and
> mechanical anchorage of some sort.
>
> Also, just to be clear, you finished with --
>>  I would suggest that it be adopted only after some testing and
>> experimentation has been done and with a warning that the results are
>> always guaranteed
>
> Don't you mean "never guaranteed"?
>
> I would greatly appreciate a copy of Harry's paper, or anything by
> Harry for that matter.
>
> Thanks,
>
> Bruce King, PE
> Director, Ecological Building Network  ( www.ecobuildnetwork.org )
> Publisher, Green Building Press  ( www.greenbuildingpress.com )
> 11 Mark Drive
> San Rafael, CA 94903  USA
> (415) 987-7271
> bruce@...
>
>
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> list, send email to GSBN@...HELP in the
> SUBJECT line.  ----
>

Athena &amp; Bill Steen
The Canelo Project
HC1 Box 324
Canelo/Elgin, AZ 85611
absteen@...
www.caneloproject.com




----------------------------------------------------------------------

Date: 8 Oct 2007 11:41:04 -0500
From: jeff@...
Subject: Re: GSBN:Re: Lime plaster problems

Bill,

I have to agree with everything you have said.  In particular, we had
the experience of delamination of the lime color coat from repair
patches in the earth base coats.  Since then, I have cautioned clients
in applying lime over earth for some of the very reasons you have described.

To explain, we had applied earth plaster base coats, which included a
small amount of lime, over plywood sheathing covered with building paper
and mesh.  There were some spots on one wall that were not applied
against the wall well enough, leaving a hollow space behind the base
coats (this was the final wall on the project and was done in the
dark).  After drying, the contractor went around poking holes in the
wall where this was the case (I am not totally convinced every spot he
poked was going to be an issue, but that is for another discussion).  We
proceeded to patch those areas with fresh earth plaster and let it dry
for a few days.  Everything appeared to dry out after a short period,
but what had actually happened is that the plaster had froze, holding
the moisture in (we were working in October with cold nights and this
was a north facing wall).  We then put the lime color coat on the entire
building.  Some warmer weather arrived shortly thereafter as it can here
in the mountains (Indian summer...).

After a week or two, on that one wall where we had patched, the color
coat was left hanging and could be scraped off with no effort on every
patched spot.  What you described as the earth base coats shrinking
during drying makes sense.  I have to admit that it took me awhile to
figure this all out myself and you confirmed my thoughts.  We have used
lime in freezing conditions with very successful results given the harsh
conditions, so to me it was an issue with the bond and the differences
in movement between the materials.

It was a good lesson to learn, and one that brought up another question
that has been in the back of my mind since.  How many small air pockets
end up behind plaster applied to framed buildings with building paper
and mesh on an average job?  I can't believe that /every /successful
plaster job on framed walls out there is 100% sucked to the wall.
Granted this wall was done in the dark and it was ultimately our
responsibility.  It was sprayed on as we have done many other times.
But no one has ever gone back to poke at the walls in the way this
contractor did, creating areas for us to patch.  It seems suction from
the trowel could easily, and unknowingly, pull the plaster away from the
wall in small spots no matter who is doing the work.  I have never
witnessed plaster failure due to this, so I cannot speak to it as a
failure mechanism.  If a contractor were to ever do that again I may
have a different response based on the experience explained above, and
was wondering if anyone else has had such an experience?

If anyone responds to this second topic specifically, maybe a new topic
is in order so as not to combine the two.

Jeff





----------------------------------------------------------------------

Date: 8 Oct 2007 15:56:57 -0500
From: jswearingen@...
Subject: Plaster on Framed Walls

 If a contractor were to ever do that again I may
have a different response based on the experience explained above, and
was wondering if anyone else has had such an experience?

I've never made a study of it, but in the many plaster walls I've torn open,
I always assumed that, to some degree or other, the plaster sheet was just
hanging there on the lath, and, when tapping on a wall with a hammer, I've
always heard plenty of things that sounded like hollow spots....

John "Hola-Hollow" Swearingen

On 10/8/07, Jeff Ruppert jeff@... wrote:
>
> Bill,
>
> I have to agree with everything you have said.  In particular, we had
> the experience of delamination of the lime color coat from repair
> patches in the earth base coats.  Since then, I have cautioned clients
> in applying lime over earth for some of the very reasons you have
> described.
>
> To explain, we had applied earth plaster base coats, which included a
> small amount of lime, over plywood sheathing covered with building paper
> and mesh.  There were some spots on one wall that were not applied
> against the wall well enough, leaving a hollow space behind the base
> coats (this was the final wall on the project and was done in the
> dark).  After drying, the contractor went around poking holes in the
> wall where this was the case (I am not totally convinced every spot he
> poked was going to be an issue, but that is for another discussion).  We
> proceeded to patch those areas with fresh earth plaster and let it dry
> for a few days.  Everything appeared to dry out after a short period,
> but what had actually happened is that the plaster had froze, holding
> the moisture in (we were working in October with cold nights and this
> was a north facing wall).  We then put the lime color coat on the entire
> building.  Some warmer weather arrived shortly thereafter as it can here
> in the mountains (Indian summer...).
>
> After a week or two, on that one wall where we had patched, the color
> coat was left hanging and could be scraped off with no effort on every
> patched spot.  What you described as the earth base coats shrinking
> during drying makes sense.  I have to admit that it took me awhile to
> figure this all out myself and you confirmed my thoughts.  We have used
> lime in freezing conditions with very successful results given the harsh
> conditions, so to me it was an issue with the bond and the differences
> in movement between the materials.
>
> It was a good lesson to learn, and one that brought up another question
> that has been in the back of my mind since.  How many small air pockets
> end up behind plaster applied to framed buildings with building paper
> and mesh on an average job?  I can't believe that /every /successful
> plaster job on framed walls out there is 100% sucked to the wall.
> Granted this wall was done in the dark and it was ultimately our
> responsibility.  It was sprayed on as we have done many other times.
> But no one has ever gone back to poke at the walls in the way this
> contractor did, creating areas for us to patch.  It seems suction from
> the trowel could easily, and unknowingly, pull the plaster away from the
> wall in small spots no matter who is doing the work.  I have never
> witnessed plaster failure due to this, so I cannot speak to it as a
> failure mechanism.  If a contractor were to ever do that again I may
> have a different response based on the experience explained above, and
> was wondering if anyone else has had such an experience?
>
> If anyone responds to this second topic specifically, maybe a new topic
> is in order so as not to combine the two.
>
> Jeff
>
>
>

>



- --
John Swearingen
Skillful Means, Inc.
Design and Construction
www.skillful-means.com


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----------------------------------------------------------------------

Date: 8 Oct 2007 20:06:34 -0500
From: cmagwood@...
Subject: Re: GSBN:Plaster on Framed Walls

Hey all,

After watching a whole bunch of bale wall panels get tested (ie, squashed)
at the lab at Queen's University, it's clear to me that it's the places
where the plaster doesn't bond to the straw that are the weak points in
the wall. Not that walls with some hollows in them are in danger of
crumbling to dust, but when they fail they fail first at those points
where the plaster was just sitting on the mesh or not making much if any
contact with the bales.

Interestingly, in plastering some of those test panels I noticed something
that I think is common on site built bale walls: the use of mesh makes it
much easier for plasterers to make plaster stay on the wall even if it's
making zero contact with the straw. Unmeshed walls force the plasterers to
get the plaster to stick to the wall itself to a much greater degree.

For those parts of a wall system that are plastered over wood or other
backings with the use of mesh, a couple things seem to happen. First, the
mesh is often stapled tightly to the wooden backing, which means the
plaster can't surround the mesh and embed it, it just sits in and on the
mesh. Where that mesh is held to the backing with only 3/8 or 1/2 inch
staples, those parts of the plaster system fail first under compression
too.

I'm not saying all of this to advocate meshless walls, as I know that the
mesh serves some useful functions too. But meshed walls do tend to have
way more hollows than unmeshed walls, in my experience.

The walls with the least hollows? Those that have been "French dipped"
which is why I like that method of building so much.

Another note about hollows: When we have explored the damp patches that
have occured on some walls up here in the winter/spring transition, the
majority of those patches occur where these hollows between bales and
plaster exist. That air space creates conditions different from where
plaster and bales make good contact. I don't think the damp patches are
causing major degradation of the walls (some we've looked at have been 10
years old and still the straw is okay), but it's another reason to stick
that stuff to the wall!

Chris

>  If a contractor were to ever do that again I may
> have a different response based on the experience explained above, and
> was wondering if anyone else has had such an experience?
>
> I've never made a study of it, but in the many plaster walls I've torn
> open,
> I always assumed that, to some degree or other, the plaster sheet was just
> hanging there on the lath, and, when tapping on a wall with a hammer, I've
> always heard plenty of things that sounded like hollow spots....
>
> John "Hola-Hollow" Swearingen
>
> On 10/8/07, Jeff Ruppert jeff@... wrote:
>>
>> Bill,
>>
>> I have to agree with everything you have said.  In particular, we had
>> the experience of delamination of the lime color coat from repair
>> patches in the earth base coats.  Since then, I have cautioned clients
>> in applying lime over earth for some of the very reasons you have
>> described.
>>
>> To explain, we had applied earth plaster base coats, which included a
>> small amount of lime, over plywood sheathing covered with building paper
>> and mesh.  There were some spots on one wall that were not applied
>> against the wall well enough, leaving a hollow space behind the base
>> coats (this was the final wall on the project and was done in the
>> dark).  After drying, the contractor went around poking holes in the
>> wall where this was the case (I am not totally convinced every spot he
>> poked was going to be an issue, but that is for another discussion).  We
>> proceeded to patch those areas with fresh earth plaster and let it dry
>> for a few days.  Everything appeared to dry out after a short period,
>> but what had actually happened is that the plaster had froze, holding
>> the moisture in (we were working in October with cold nights and this
>> was a north facing wall).  We then put the lime color coat on the entire
>> building.  Some warmer weather arrived shortly thereafter as it can here
>> in the mountains (Indian summer...).
>>
>> After a week or two, on that one wall where we had patched, the color
>> coat was left hanging and could be scraped off with no effort on every
>> patched spot.  What you described as the earth base coats shrinking
>> during drying makes sense.  I have to admit that it took me awhile to
>> figure this all out myself and you confirmed my thoughts.  We have used
>> lime in freezing conditions with very successful results given the harsh
>> conditions, so to me it was an issue with the bond and the differences
>> in movement between the materials.
>>
>> It was a good lesson to learn, and one that brought up another question
>> that has been in the back of my mind since.  How many small air pockets
>> end up behind plaster applied to framed buildings with building paper
>> and mesh on an average job?  I can't believe that /every /successful
>> plaster job on framed walls out there is 100% sucked to the wall.
>> Granted this wall was done in the dark and it was ultimately our
>> responsibility.  It was sprayed on as we have done many other times.
>> But no one has ever gone back to poke at the walls in the way this
>> contractor did, creating areas for us to patch.  It seems suction from
>> the trowel could easily, and unknowingly, pull the plaster away from the
>> wall in small spots no matter who is doing the work.  I have never
>> witnessed plaster failure due to this, so I cannot speak to it as a
>> failure mechanism.  If a contractor were to ever do that again I may
>> have a different response based on the experience explained above, and
>> was wondering if anyone else has had such an experience?
>>
>> If anyone responds to this second topic specifically, maybe a new topic
>> is in order so as not to combine the two.
>>
>> Jeff
>>
>>
>>
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>
>
>
> --
> John Swearingen
> Skillful Means, Inc.
> Design and Construction
> www.skillful-means.com
>
>
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