Hey Riley,
I was sent an inquiry from one woman working in Mexico and another working on a wall in Wisconsin, which I fwd to Eric, 'cause I know he's worked in both places. I'm interested to know if your experience jives w/ his regarding sealant and use of latex-enhanced thinset. Are you familiar w/ the Laticrete 4237 plus sanded grout formula for thiniset/grout combo? Seems we've discussed it, and I've been using it for more than 10 yrs.
Thx,
g
Gonna have to postpone our discussion of your repair pics a bit.
----------
> From: Eric and Lindsay Rattan <eric@santafedesignstudio.com>
> Date: Tue, 25 Jan 2005 21:07:41 -0600
> To: George Fishman <gfmosaics@bellsouth.net>
> Subject: Re: mosaic mural in cold climate
>
> Hi George, Here are some thoughts on Wis. exterior mural. Sealed
> concrete wall. Yes, ---scratch, sand or sandblast to insure mech.
> bind, and make sure the mosaicist is using the word concrete correctly.
> It is frequently used incorrectly. Signs of stress on wall may call for
> and underlayment or reinforced mortar after sandblasting. THINSET be
> sure exterior grade TILE Not all glazed porcelains are frost free .
> Call manufacturer for tech. data. Call Eric for home test 608 231
> 1883. Glaze fitting is a potential bomb here. (tech. ceramic term) Sanded GROUT
> and a homemade course silica has some advantages. Call Eric to
> discuss. No sealers. I don't recommend using a grout and additive for
> setting tiles unless there is a real good reason, such as transparent
> tiles where adhesive shows.
SEALER no! Stone /ceramic sealers are vapor
> permeable which is a must but they hold as much moisture in as they
> keep out so in the masonry trades sealing can be a cause for
> failures.
CURING The old standard of damp curing cementitious
> applications is still valid today except for many additives such as
> latex. Latex additives can effloresce and most grout companies do not
> want you to damp cure latex mod. grouts. The additive slows down
> hydration so damp curing is redundant and often harmful. If you feel
> like you must seal (shower stall, soap scum ) for example, wait 30 days
> minimum. Mosaic books are riddled with artsy craftsy info. I review the
> tech sections of these books and am amazed at what I read. While I
> appreciate the books and have purchased many, they are generally a very
> poor choice for tech. info. That is the nice way of saying it.
MEXICO wall. 30 days to let new stucco finish cure before applying tessarae.
> In many cases this is impractical so it is generally safe to procede
> after 2 wks. This is a good place to damp cure and use a reinforced
> mortar. If you cannot find nylon or fiberglass for your sandmix use the
> centuries old standby---- horsehair. It is every bit as pemanent as
> nylon or fiberglass. If there is a seismic factor here call Eric for
> info. Because of the many many variables , I do not answer tech. Q's
> from artists by email but phone only so I can get to the bottom of Q's
> like. Is the wall really concrete? Describe the wall. and so on and so
> forth. I don't trust this machine so let me know if you rec. this
> Thanks George.
> On Jan 25, 2005, at 9:19 AM, George Fishman wrote:
>
>> Hey Eric, regarding the Mexico project, if they put new mortar on the
>> wall,
>> how long should they wait before applying thinset? Could you pls add
>> that,
>> as well as any other suggestions for her.
>> Thx, g
>> --
>>
>>
>>
>>> From: George Fishman <gfmosaics@bellsouth.net>
>>> Date: Mon, 24 Jan 2005 15:13:49 -0500
>>> To: Eric Rattan <eric@santafedesignstudio.com>
>>> Subject: FW: mosaic mural in cold climate
>>>
>>> Hi Eric, if there's anything you would like to add...... (or delete!)
>>> All the best,
>>> g
>>>
>>>
>>>
>>>> From: George Fishman <gfmosaics@bellsouth.net>
>>>> To: "C. O'Malley" <carrieomalley@hotmail.com>
>>>> Subject: Re: mosaic mural in cold climate
>>>> Date: Mon, 24 Jan 2005 14:44:16 -0500
>>>>
>>>> Hello Carrie,
>>>> Congratulations on your new project.
>>>> For starters, I would suggest you read these and other publications
>>>> of the
>>>> CTI.
>>>> http://www.ctioa.org/reports/fr37.html
>>>> http://www.ctioa.org/reports/fr93.html
>>>> Here's the general list:
>>>> http://www.ctioa.org/index.cfm?pi=FR
>>>>
>>>> 1. Be sure the wall is smooth and flat. Any bumps and dips will be
>>>> "telegraphed" to the surface of the mosaic, unless you're using
>>>> mat'ls of
>>>> varying thickness, which will require a lot of thinset anyway. (thick
>>>> thinset!)
>>>>
>>>> Verify that surfaces to receive mortar setting bed and tile are
>>>> firm, dry,
>>>> clean, and free from oily or waxy films and curing compounds.
>>>>
>>>> If the concrete substrate has a hard steel trowel finish or if curing
>>>> compounds were used, then the concrete must be heavily scarified. If
>>>> sealant
>>>> was applied, I would do a test, because some sealants will tend to
>>>> "shed"
>>>> thinset -- bad news.
>>>>
>>>> 2. Don't use absorbent wall tiles or soft, absorbent stones (ask your
>>>> suppliers). As a rule of thumb, if water dripped onto the back of a
>>>> tile
>>>> gets absorbed, don't use that kind of tile. Commercial floor tile,
>>>> including
>>>> quarry tile, is generally non-absorbent, so are porcelains (glazed or
>>>> unglazed); glass is good too. Otherwise, moisture soaked into the
>>>> tesserae
>>>> will freeze/expand and pop loose or pop their glaze.
>>>>
>>>> 3. Use a latex-enhanced thinset (or epoxy, though epoxy is
>>>> considerably
>>>> trickier). Laticrete's sanded grout can be mixed with their #4237
>>>> additive
>>>> will create a colored thinset that can also be used for grouting.
>>>> Mapei (and
>>>> probably other manufacturers) makes comparable products.
>>>>
>>>> 4. Dampen, then cover work completed each day with brown Kraft paper
>>>> to
>>>> control drying/curing.
>>>> This will help keep grout from developing a mottled appearance.
>>>>
>>>> 5. Even after using the best setting materials, be sure to apply a
>>>> penetrating sealant (generally after a minimum of three days after
>>>> grouting). This is critical to keep the same freeze problems from
>>>> occurring
>>>> with the grout/thinset. Normally, sealant needs to be re-applied
>>>> after 6
>>>> months or a year.
>>>>
>>>> 6. Some installers prefer working from the top down, so that thinset
>>>> and
>>>> grout drips don't fall on the just-installed sections. Others prefer
>>>> to work
>>>> from the bottom up, taking advantage of "stuck" sections to keep
>>>> progressive
>>>> sections from sliding down. This is mostly an issue if you're using
>>>> a face
>>>> or mesh mounting system. If you're not familiar with face and mesh
>>>> mounting,
>>>> you need to buy one of the many recent books on making mosaics.
>>>>
>>>> Another good source of information is the Yahoo Mosaic Artists
>>>> Organization
>>>> newsgroup
>>>>
>>>> Good luck!
>>>>
>>>> So, here's my question:
>>>> I am going to be doing an exterior wall at a school (I live in
>>>> Wisconsin -
>>>> lots of freezing and thawing in winter - and high temps and humidity
>>>> in
>>>> summer) and would like your recommendations for products.
>>>>
>>>> First, if the concrete wall is sealed, what do I do? Any prep work
>>>> that you
>>>> recomomend? Second, should I use thin-set as the adhesive for the
>>>> tiles.
>>>> Thirdly, what tiles fair best in this climate outdoors? I would
>>>> like to use
>>>> glazed ceramic because it will go quicker (the wall is over 20 feet
>>>> long).
>>>> Do you have a grout and additive that you would recommend? Sealer?
>>>> Any
>>>> other tips?
>>>
>>>
>>
>