Our shower floor is tiled and we don't get any mildew in the sanded
grout lines between the tiles, but we do have an unsightly amount of
mildew in the "silicon-ish" (not sure what the actual matrerial is)
caulking where the tiles hit the walls. I think I already know the
answer, but is there any miracle product that will get rid of that
mildew, or am I doomed to having to remove this mildewed caulking and
replace it with some mildew-resistant variety.
Surface mildew will go away after using bleach. If that doesn't work, get a
razor blade, scrape out the old caulk, and re-apply new silicone (not latex)
caulk. It won't mildew (nor can you clean it with water, so get the
appropriate solvent, just in case you make a mess).
The bottom joint should be GROUT not caulk. Grout is porous and will
allow the moisture soaking through the tile grout lines to the water
proof membrane to run down and drain out. Most people caulk this joint
and get the same result. The tile grout is NOT water proof unless
sealed with silicone and that needs to be re-applied every so often.
Remove the "caulk" and re-grout the joint properly. Tub/shower walls
are a "system" that is designed to shed water back to the tub or shower
pan where it will drain away.
Interesting. A Pella rep recommended no caulk for the outside bottom of an
exterior door for the same reason. In case somehow water got in he wanted a
way for it to get out. Note that I am talking only of the bottom outside
edge. The inside bottom gets a wide bead as the door is installed.
I'd like to suggest that you use the bleach first.
(Removing old stuff and resealing the tub with mildew-resisting
silicon is... well... not as convenient.)
You could try a "bleach in a spray bottle" (something like Tilex), but
(unless you already have one) don't go and buy it just to try it;
1. It is very expensive considering what's in it.
(It is usually something like 2.75% bleach.)
2. Even though the spray is very convenient (it is a rustproof
all-plastic construction by the way), the content is not very
effective against really scummy mildew ^_^
(Again, it's only about 3$ bleach).
The "after-shower spray" doesn't count here.
The good old bleach products in a gallon jar that we are familiar with
(Clorox and such) are about 5.5% bleach.
That's double the strength of the bleach spray.
These "Gallon" jars, however, are often replaced with new and smaller
"Concentrated Ultra bleach" products.
Hey, I suppose that's better for the purpose since it should be even
If you have a bottle of bleach spray, use (...and empty) the content
on the mildew and the tub.
(You can refill/recycle the empty bottle with even stronger
Let it sit for 15 minutes.
Wash it away with warm water.
Clean the area gently with used toothbrush/brush to remove scummy
flakes if you want to.
If that works, good!
If not, you can use the "Ultra" bleach couple more times.
Just be sure to let it sit for 15-20 minutes each time.
If bleaching doesn't work...
It's time for DIY home improvement. -_-
firstname.lastname@example.org (Dolchas) wrote in message
It will be easier in the long run to remove the gunk, clean
immaculately, and replace with new silicone caulk. Make sure soap scum
and hard water deposits are removed, wipe down finally with bleach. My
troubles with cruddy caulk have been with mold/mildew beneath it, so no
way to fix but to remove and start clean. It is worth the effort.
This is something I'm curious about: Is silicone more mildew resistant
than acrylic caulks? The word I've been getting is that both kinds
of caulk from a given manufacturer contain the same mildew-suppressing
agent. Given that, is there some reason why silicone should nevertheless
be better in this regard?
Mike Lacy, Ft Collins CO 80523
Just my opinion:
I've tried Dap Acrylic, GE I Silicone, and GE II Silicone tub and tile
caulks. The Dap, and GE II caulks all mildewed in under a year. THe GE I
sillicone is still going strong after 2 years. I believe it to be somehow
related to the paintability of it. DAP and GE II are paintable and GE I is
not (super slick). Maybe the same reason it's paintable also provides a
foothold for mildew.
To remove mildew, roll apaper towel up and wet it with dilute bleach and lay
it on the caulk. Put a piece of clear plastic wrap over it to prevent
evaporation and let sit over night. This is only temporary as the mildew
will come back within a few months. You really need to remove the caulk and
start over again.
I have also tried a product called Insti-gone (available from Walgreens - as
seen on TV). IT's very high priced ($19) and works no better than bleach.
There are a number of mildew sprays, but they basically have bleach in them,
so once you use up the SP14 or other anti mildew spray, pour pure Chlorox in
there, and take advantage of the bleach-resistant pump parts in those
sprayers. Spray once, the surface mildew is gone after soaking for several
Your caulking likely is one of the cheaper white caulks, which mildew lives
happily on. Best to get a very sharp utility knife blade, razor blade, or
sharp small chisel, and peel it off, cleaning up with a flat razor. Then
clean area spotless, dry completely, before applying silicone bath caulk
from a cartridge, pressing it in with the nozzle as you go. Let set for a
day, in dry conditions.
Yes, I have found GE Silicone bath and tile adhesive caulk is best. Don't
get the paintable, nor the Dap or creamy white products. GE Silicone used
to have small amounts of arsenic to repel mildew. I dont know what the
additive is now, but it works, and the surface of Unpaintable Silicone seems
smoother and shinier, making it easier to remove the mildew once it forms,
and harder for it to get a foothold in the first place...
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