On 11/6/2011 11:15 AM, RicodJour wrote:
On Nov 5, 4:59 pm, wrote:
On 11/5/2011 9:44 AM, RicodJour wrote:
On Nov 4, 8:34 pm, wrote:
On 11/4/2011 6:13 PM, RicodJour wrote:
On Nov 4, 4:50 pm, wrote:
On 11/4/2011 3:43 PM, chaniarts wrote:

corners are especially bad for grout cracks. they should have been
caulked instead. you probably need to remove the grout and caulk to get
a final solution.

No need to go overboard removing the grout...just enough for the caulk
to grab into (it sticks to the surface of the tile ennyhoo).

I suppose that is why some mfg. label the product "adhesive caulk". Or not.

Gotta call you on that one. The caulk will stick, but it won't be
long lasting and it won't be gua-ran-teed to be 100% waterproof.
It's not all that much work to remove the old grout and clean out the
joint. Do it right, do it once.

Gotta call you on that one. My caulk will stick for a long time...clean
the meeting surfaces obsessively, wipe with full strength bleach, let
dry, caulk. Done (unless I smudge it and have to do it over) )

You're not arguing with me, you're arguing with the physical
properties of caulk. Caulk won't stretch in every direction equally
regardless of area of adhesion and thickness. Unless you control the
joint width and depth, and insure that the narrow dimension is normal
to the direction that the joint will move, the caulk will fail.
Murphy's Law requires it to fail in a way that is most unfavorable to
your desired outcome - waterproofing.

The narrow dimension is normal to the direction that the joint will
move? Pray tell, what does that mean? And the average homeowner
determines which way the surfaces move how?

Some people just goober on the caulk right over the grout and bridge
the joint. That may work for a while, but it's a non-starter if you
want the job to last and don't want the caulk job to yell out,
"Amateur!" Caulked joints should be almost indistinguishable from a
grout line - uniform along it's length, color matched, and as close to
the standard grout line width as possible.

Wide enough to cover the joint.


It's pretty unlikely to find a corner joint with tile where the gap is
as fine and even as a grout joint

Look at any of my tile jobs and you'll see they're all like that. It
takes longer, but I'm only doing it once. But it doesn't matter how
big the gap is, within reason, it matters how you approach caulking
the joint. Filling the joint, or attempting to bridge it, without
taking into account the caulk bead depth and dimensions is a surefire
recipe for failure.

...and stretching is only minimal;
consider how wide the fine crack is if the joint is grouted. We're not
talking about trampolines.

The water we have around here does not discriminate based on the size
of the gap. If there's a gap, the water will enter it. It's a
shower, eh?

Your water apparently works a lot like mine. I clean the joint
meticulously...degrease, scrape, bleach, dry, denature alcohol just for
good measure, dry, then caulk. Usually with tape. I make the caulk
smooth so that there is nowhere for moisture to sit and grow mold.

As far as the amount of stretch - that's exactly the point. You don't
fight the material, you work with it. The caulk should be adhered at
both sides and the caulk thinner in the middle so it'll stretch the
way it is supposed to and not pull the caulk away from the tile on one
side.

LARGE surfaces need expansion joints, blah, blah. A shower stall isn't
large, and is probably the least likely of installations to have
expansion. Have never seen one that would require backer rod, and an
installation with backer rod is quite a different deal...some nasty
tub/wall joints leave room to store valuables )

Different ways to caulk correctly:
http://www.inspectapedia.com/BestPra...Figure1-38.jpg
http://www.inspectapedia.com/BestPra...Figure6-37.jpg

Carpentry, but it applies to tile as well:
http://www.thisiscarpentry.com/wp-co...kerRod-1_1.jpg

Shows preferred caulk bead dimensions:
http://www.jlconline.com/isroot/jlco...01Mc51.eps.gif

This is all well established caulking practice. You appear to be
saying "it doesn't matter", but it does. A slow leak is not better

Guess you didn't read my post, or just like to argue. The part of my
post, which you quoted above, says, "...enough for the caulk to grab into".

than a fast one. A big gap/leak will show up more quickly and is less
likely to do extensive damage. A small gap/leak can go undetected for
years, and then when it is finally discovered it is never good.
Reframing and mold remediation are the usual outcomes.

R
I've caulked indoors and out, with and without backer rod, different
types of surfaces...it's funny how horrible people can make a poor caulk
job look )

We installed a pressed glass panel for a backsplash behind kitchen
cooktop that covers about 6' wide wall, held in place with clear
silicone. The size and pattern of the glass required two pieces, with
very slightly beveled edges. I bridged the joint with clear silicone,
filled only to level with surface, and the joint is invisible. I love
the way it looks and the ease of cleaning it...nothing better. $60. If
I got tired of it, I could take it down and replace it.