|I use the GE silicone caulk which claims "no mold for ten years"
| Yeah right.
| Does anyone know of a bathtub caulk that just plain will not mold?
I like Phenoseal for almost everything: caulking trim
and woodwork for painting, as well as caulking tubs.
I don't know of anything that's actually mildew-free.
(I assume you mean mildew and not mold.) But I
have found that silicone is *worse* than other
types of caulking when it comes to encouraging
No, I don't know of any bathtub caulk that won't mildew, but I clean
mildew off the silicone caulk around my 20+ bathtubs all the time, and
I'm very good at it.
1. A box of 20 Mule Team Borax which you should be able to find in the
laundry detergents aisle of any supermarket
2. At lease a quart of bleach. Chlorox and Javex will be 6.25 percent
NaOCl, whereas no-name bleach will be 5 percent NaOCl. Get the stronger
3. A roll of Saran Wrap, or any cling wrap. Nowadays, I use a 6 inch
wide tape called "Pre-Mask", but I used cling wrap for years with the
same good results. Cling wrap can be hard to work with because it
sticks to itself, but if you're willing to throw the odd piece out cuz
it's mucked up, you can use cling wrap instead of an adhesive tape.
A. Add some bleach to a mixing container and add Borax powder. Mix with
a strong spoon. The mixing container will get quite warm. Keep adding
borax and mixing until you get a slurry that will more or less hold it's
shape. (It's the bleach that's the active ingredient in killing mildew,
so you can mix the bleach with any powder, but I find Borax works best
because boron is a natural fungicide and the borax/bleach mix tends to
be stickier and so it sticks to vertical surfaces well.)
B. Mix the slurry until reasonably smooth with the large spoon, and
then scoop slurry out of the mixing container with the large spoon and
spread it over the mildewed silicone caulk with a tea spoon, or any size
spoon that will cover the caulk completely.
C. Cover the bleach/borax slurry with cling wrap. Here it's best to
have a helper cut the cling wrap to lengths for you. You want to cover
all of the bleach/borax slurry to keep it from drying out.
D. Leave the bleach/borax slurry on the mildewed caulk overnight, or
longer if possible. In my case, I typically leave it on for several
days or even weeks when a suite is empty, but it's not necessary to
leave it on for that long. If you leave it on even overnight, your
silicone caulk should be white as Manitoba snow when your remove the
slurry with a putty knife.
E. Borax is highly soluble in water, so any dried up borax slurry that
you don't remove will be washed away by the shower water.
I clean the mildew off of silicone caulk after every tenant vacates.
The only time I don't need to do that is when the tenant had baths
instead of showers.
I should say that when the mixing container gets warm to the touch, the
borax and bleach slurry will get stiff and quite difficult to mix. Just
keep adding small amounts of bleach and mixing it in with the stiff
borax until the heating stops. Continued mixing will result in a
reasonably smooth and spreadable slurry. This stuff remains effective
for days, so don't rush the mixing process. You're better off to spend
more time mixing so that you get a smooth spreadable slurry than mixing
less and having lumps of borax in your slurry.
I really don't know what causes that exothermic reaction when you mix
bleach with borax, but it happens every time.
That's great info, nestork! I will give this a try here. I know from
other types of cleaning, that one of the key points is to let the
cleaner sit, then scrub a little, and let it sit some more.
You probably have a tip for this, too.... Shower stall is tile. I have
used 1 cup bleach, 1 cup Spic-n-Span powder in a gallon of hot water.
Sponge it on, let it sit and scrub it off. Last time I couldn't find
Spic-n-Span anywhere, and used TSP instead. This works find if the
mildew is not too bad.
One shower was badly stained where the floor meets the sides, and I have
never been able to get it. To make it worse, someone (me) tried sealing
it and covering up the stain with caulk before I knew any better. It's
near impossible to scrape the caulk off.
Anyway, that's were I'm at now. Any ideas how to deal with this?
I'm not sure if this is the same as Boraxo Powdered Hand soap, but I
want to praise that. Other than the creams that come in cans or plastic
tubes that take the grease and oil out of pores, Borax Powdered hand
soap is the best soap there is for really dirty hands, Probably don't
need a brush when you use it.
Although I've been looking for a hand brush that isn't too soft or hard,
and I ended up going with a brush meant to wash the car, shapped like
the bottom of an iron or a rowboat.
Thanks for the replies.
I did find something that does a great job of cleaning the tub.
My wife uses "Bristle Magic" to clean her paint brushes and we tried it
on the tub and it works very well.
Too bad the caulk needs to re-done once a year no matter what.
I will try the cheap non-silicon stuff next time.
| Get yourself:
| 1. A box of 20 Mule Team Borax which you should be able to find in the
| laundry detergents aisle of any supermarket
| 2. At lease a quart of bleach. Chlorox and Javex will be 6.25 percent
| NaOCl, whereas no-name bleach will be 5 percent NaOCl. Get the stronger
Your method may be the best. I haven't tried it. But
in most cases I find that 2 "paintings" with full-strength
bleach is enough to make mildew disappear within a few
minutes. I guess I've never explored anything more
thorough because usually if there's bad mildew, the tub
caulking needs to be redone, anyway. And it's not really
a lot of work to just scrape it off and redo it.
There is no such animal. The secret is, first, applying to an
absolutely dry and CLEAN surface.....scrub/scrape off all soap/residue,
rinse, wipe with full-strength bleach, let dry, and for a finishing
touch wipe with denatured alcohol. Then, apply caulk that is absolutely
smoothe, with no ditches, bumps, lumps so that it doesn't trap moisture
and crud that mildew feeds on. Then, ventillate the room so the area
dries; I keep shower curtain open on both ends when not in use so it
doesn't hold moisture. In an older bath, I put in a timer on the
exhaust fan so it would clear steam after showers.
There is no mildew in present bathroom or the last. I found out while
regrouting a tiled shower stall that clean appearing (matte) tile can
hold an amazing amount of soap film; I couldn't figure out why, after
scrubbing the tile, I could still smell soap....until I took out my
razor-blade scraper and scraped off a considerable amount of old soap
film (35 y/o tile install).
Use a good cleaner on a regular basis and you won't get the mold.
Step one is to buy a good squeegee. Oxo makes one with a suction cup
and it can be put right in the shower. Takes 20 to 30 seconds to get
rid of most of the moisture after a shower.
I use a cleaner from the Dollar Tree call Amazing Awesome Cleaner. You
really can beat this stuff. It is like the expensive versions of 409
but concentrated. Best deal for cleaner int he world, IMO.
Also helps to keeps the bathroom from getting too humid. Vent fan or
crack the door open while showering.
> other types of cleaning, that one of the key points is to let the
> cleaner sit, then scrub a little, and let it sit some more.
> used 1 cup bleach, 1 cup Spic-n-Span powder in a gallon of hot water.
> Sponge it on, let it sit and scrub it off. Last time I couldn't find
> Spic-n-Span anywhere, and used TSP instead. This works find if the
> mildew is not too bad.
> never been able to get it. To make it worse, someone (me) tried sealing
> it and covering up the stain with caulk before I knew any better. It's
> near impossible to scrape the caulk off.
To remove silicone caulk, use a Dap product called "Silicone-Be-Gone"
which you should find in the paint and caulking aisle of your local home
center. This product is really nothing more than gelled mineral
spirits, and mineral spirits will SOFTEN cured silicone caulk. Mineral
spirits will not dissolve cured silicone caulk, only soften it so that
it can be removed by mechanical means, such as scrubbing with a
Often, people have trouble getting silicone caulk to stick to tub and
tile after supposedly removing the old silicone caulk. The reason
they're having a problem is that they haven't removed the old silicone
caulk COMPLETELY. The way to tell if you've removed all of the old
silicone is to wipe off the Silicone-Be-Gone with a damp sponge. Then
sprinkle a fine powder like portland cement onto the area where the
silicone caulk was and rub with your finger. The powder will become
embedded in the soft silicone caulk, revealing the location of the
remaining silicone caulk. Now, use the Silicone-Be-Gone on only the
areas where there's remaining silicone caulk. Repeat this procedure
until all of the portland cement powder wipes cleanly off tub and tile
indicating there is no remaining silicone caulk. NOW, the new silicone
caulk will stick well.
If you're having trouble removing mildew from old grout, the usual cause
is that the bleach you're applying is not being drawn by capillary
pressure INTO the grout, and the usual reason for this is that the
porous surface of the grout is all clogged up with soap scum. Use a
phosphoric acid based toilet bowl cleaner to dissolve that soap scum.
Phosphoric acid toilet bowl cleaners will be gelled so that they're
thicker. After applying the phosphoric acid, use a rubber squeegee to
remove the toilet bowl cleaner to the grout lines and let it sit for a
minute and then scrub the grout lines with an old denture brush or any
stiff nylon bristle brush. That will remove the soap scum from the
surface of the grout so that when the wet surface of the grout dries, it
will wick bleach in by capillary pressure, and that's the key to
cleaning grout with bleach.
If you're going to be cleaning mildew off silicone, it's important to
have a STRONG and large spoon both for mixing the bleach and borax
slurry and for scooping it out for spreading on the silicone with a
teaspoon. Go to any place listed under "Restaurant Equipment &
Supplies" in your yellow pages and buy a DESSERT SPOON for $2 or $3.
The strongest spoon in any place setting will be the dessert spoon
because it's meant for digging into hard ice cream and fudge. The tea
spoon and soup spoon are weaker because they're meant for use with
liquids; not for eating hard ice cream or fudge. You need a strong
spoon like a dessert spoon to mash the borax against the side of the
mixing container to make for a smooth and spreadable slurry.
Borax is different from Boraxo, but hard to find. Not enough profit it
for most stores to carry, compared with the proprietary cleaners.
Target carries a small pkg. Walmart has 76oz box at almost the same
price as the small one at Target.
Their stuff is definitely awesome. I buy their liquid soap 1/2 gallon
for $1. It's just plain old utility hand soap - no lotions or perfumey
stink. Probably not something for baby. Burns like hell if you get it
in your eyes. But then your eyes are really clean.
I've never had any trouble finding 20 Mule Team Borax in the laundry
detergent aisles of supermarkets.
Once again, the powder you mix with bleach doesn't HAVE TO BE borax.
You'll get the same good results if you use talcum powder (magnesium
silicate) or any other powder. So, if Boraxo is a powder, I'd use it.
The problem is that some powders are heavier and tend to segregate to
the bottom of the mixing container. Borax does that too, but quite
slowly, so if you mix your slurry periodically, you'll keep the borax
well suspended. Also, the reason I use Borax is that the slurry you get
is a little stickier than using other powders, and that helps when
applying the slurry to vertical surfaces or even overhead. But, the
whitening action is entirely the work of the bleach, so if you can't
find Borax, use whatever powder you can get. The cleaning action will
the the same regardless of what powder you use.
Also, Borax in the factory cardboard box tends to get lumpy from
absorbing moisture from the air, so maybe salvage the next 2 liter pop
bottle you're about to throw out and use it as a moisture proof storage
container for your borax.
And, of course, bleach gradually turns into salt water given time, so it
gets weaker with age. But, I've found that using old bleach cleans up
the silicone caulk as well as new bleach, or at least I haven't noticed
any difference in performance.
Any caulk will mold over time. The best you can do is
1. Have ventilation when you bathe(ceiling vent fan, or open window).
2. Afterwards, leave curtain or showerdoor open to let moisture out.
3. Wipe excess water off caulking.
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