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mold in bathroom

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Jan 10, 2012, 07:05 AM
mold in bathroom
i have mold in my tub and shower area. there is a window there for ventilation, a vent fan is not an option at this queston is, is the mold forming because of airflow or do you thing not enough insulation be hind the wall. it is tiled inside tub area. am getting ready to remove all tile and replace it with new,just curious if i should go further,wallbaord removal etc.thanks in advance.
Jan 10, 2012, 08:07 AM
How far you have to go will be answered when you start removing tile etc. If the backer is moldy or damaged (more likely if it's older style greenboard or plaster) then it will need to be replaced. Once you remove the backer, then you can see if any framing has been damaged. At that point, it's a matter or killing mold or replacing damaged framing (or both) and building back to a solid backer surface for the new tile surround.

If you do have mold and moisture damage within the wall, causes can range from leakage through the tile and backer (especially if a wall liner material was not used)or leakage around that window if it's located within the surround area. Obviously when you build back you may have to redesign to avoid a repeat in a few years.

Jan 10, 2012, 08:28 AM
thanks for the info,was afraid that could be the problem,it has been going on for sometime,but i want to do remodel anyway so this may be my chance,thanks again will keep ypu informed of the outcome.
Jan 10, 2012, 08:32 AM
I agree with Jaybee and replace any product tainted with mould growth. And commercial mold inhibitors are available @ hardware stores and with a bit of internet knowledge can be safely applied. Good luck. PS, according to the NEC a fan is required install in bath remodels, window or not. Wink

This message has been edited. Last edited by: CommonwealthSparky,

Popeye only reached for the Spinach can as a last resort...
Jan 10, 2012, 02:25 PM
mold needs three things to thrive... water, food (any organic material,) and neglect. welcome to the 99%, it's common.

if you have tiles walls with mold, unless they were done recently and badly, you are going to have sheetrock behind the tile. there will likely be some damage behind the sheetrock. cut a hole behind the faucets and drains, because what the hay, there should be an access panel there anyway, and look. if so, it's a total gut job -- take out the wall to the studs, check a test hole in the ceiling, remove the tub and check underneath, all that good stuff.

which is a perfect opportunity to replace any bad wood, use proper techniques from online or a book at the home center, and rebuild it right. cement board instead of drywall, waterproofing up and down, thermal-protected faucet control, any funky wood replaced, discolored wood dried, strength-tested (can't poke into it) and sterilized, all that stuff.

you can install an exhaust fan through-wall an arm's reach plus inches away from the shower if you don't have access above.

we are assuming this is your home, not a rental. the landlord has complete right of refusal of any and all alternations, for insurance reasons or other.

sig: if this is a new economy, how come they still want my old-fashioned money?
Jan 10, 2012, 08:28 PM

I think things are getting out of hand when people presume that just because mildew is growing in a tub/shower area it necessarily means there's water damage to the walls behind the tiling.

What you should do is clean up that mildew with some bleach. Dilute the bleach with 10 parts water and use that to clean the area. If you kill the mildew you can see it will miraculously repair all that water damage behind the tiling for you. Cool

Swshrad was correct in telling you that mold, like anything else, needs food. The food it eats is the fragments of vegetable oil molecules (called fatty acids) that you find in bar soaps. Mildew will grow wherever there's a plentiful supply of both water and plant oils (such as on any surface painted with old linseed oil based paints), and that's why painting bathrooms with linseed oil based paints tends to make the problem of mildew growth in the bathroom worse.

There are a few things you can do:

1. Switch from having showers to having baths. When you have a bath, the soap you get on your body mostly dissolves in the water and goes down the drain. The result is that there's no supply of soap splashed all over the walls around the bathtub, and so there's no food on those walls for mildew to eat. Simply put, the walls of a bathroom where people only have baths will be largely free of mildew because the tiling simply can't support mildew growth for lack of food on it's surface.

2. Switch from bar soap to a "Lipid" free cleanser like Cetaphil or Aquanil. A fatty acid from vegetable oils and other molecules of similar form are all collectively grouped together under the name: "Lipids". By switching from bar soaps (which are made from vegetable oils) to lipid free soaps (which aren't), you can continue having showers but still effectively deny the mildew a food supply. Some people have skin that's sensitive to lipids, and so pharmacies will sell Lipid Free Cleansers like Cetaphil and Aquanil, but they'll work equally well on people that don't have sensitive skin.

The other plus side of using a Lipid free cleanser is that you won't have any more soap scum on your tub or sink. You see soap scum forms when a soap molecule, which was previously attracted to a single sodium (Na+) ion, gets attracted to a Ca++ or Mg++ ion in the water (or three soap molecules are attracted to a single Fe+++ ion). The result is that instead of a long hydrocarbon chain with a sodium atom on it's end that is strongly attracted to water, you have two long hydrocarbon chains sticking out into the water with a Calcium (Ca++) or Magnesium (Mg++) ion in the middle of them (or three hydrocarbon chains with a central Iron (Fe+++) ion. Before, it was the strong attraction between the Na+ ions and the water that kept soap molecules suspended in water. There's no attraction at all between those long hydrocarbon tails and the water, so as soon as two or three soap molecules cluster around a central hardness ion, the solubility of that combination of molecules in water goes WAY DOWN. So, soap scum is nothing more than soap that's lost it's solubility in water.

Lipid free cleansers don't have fatty acids in them, and it's those fatty acids which are the long hydrocarbon chains that cause soap scum to not have any affinity for water. So, by using Lipid free cleansers, you avoid the formation of soap scum in the first place, and consequently you don't need to clean soap scum off your bathtub and sink anymore. (This is precisely the reason you never see a soap scum ring in your kitchen sink... you don't use bar soaps in your kitchen sink or washing machine, and it's only bar soaps that have those fatty acids in them that give rise to soap scum.)

The other thing to keep in mind is that we humans evolved on this plant IN THE PRESENCE of molds and fungii. Generally the spores from molds have a limited effect on our health. Those molds that do have an effect on our health do so by producing spores, and those spores have chemicals on their surface which are collectively called "mycotoxins". It is these mycotoxins that affect our health. For most people, the effect of inhaling air with spores that have mycotoxins on their surface is typically that of an allergic reaction... runny nose, headache, drowsiness, that kind of thing. Lots of people have worse reactions and lots don't show any effect on the health at all, that's because we're all different and some of us are more susceptible than others. However, the health effects from inhaling spores are generally pretty minor.

It's true that you CAN get seriously sick and even die from ingesting large amounts of mycotoxins, and lots of mold contractors will try to convince you that inhaling mold spores can make you that sick, but that's simply not true. The only time you can ingest so much mycotoxin as to get seriously ill, have internal organ failures and even die is if you eat the wrong kind of mushroom. You will never even come close to that kind of threat to your health from inhaling mold spores.

And, also, the effects of mycotoxins on your health are short lived. Once you are in a place where you're not inhaling those spores, the health symptoms clear up within a few days.

And, it's important to remember that only a small number of molds and fungii produce mytotoxins. That vast majority of molds and fungii don't, and just because a mold is black and grows on a bathroom wall, does not mean that it produces mycotoxins.

Toxic mold is becoming the next big health scare just like asbestos used to be. Did you know that in the 1970's the airborne asbestos fiber count in the parks around San Fransisco was measured to be 50 times higher than the OSHA would allow in a workplace today without special protective respiratory equipment being provided to the workers? It's true. Virtually all the rock in California is asbestos bearing rock, and it was a rock particularily high in asbestos called "Serpentine" that was quarried to make the gravel roads through the parks near San Fransisco. When cars would drive over these gravel roads the stones would grind together under the tires and create clowds of airborne asbestos fibers. And yet, no one ever noticed that the park rangers around San Fransisco were getting lung diseases at rates any higher than the average population. We're all individuals, and some of us are more prone to get certain kinds of disease and some of us are less so. And that applies to everything, including mesothelioma from asbestos to cancer from smoking to liver disease from drinking to health effects from mycotoxins. If your mildew hasn't made you sick by now, it's because your mildew doesn't contain any mycotoxin producing fungii and/or you're not susceptible to suffering any health effects from inhaling mycotoxins.

So, there's no need to start tearing apart your bathroom walls to eradicate molds that there's no reason to believe is even inside those walls in the first place.

You have a lot of mold because you have a lot of mold. The more mold you have growing in your bathroom, the more spores are produced and the more mold grows. That is, the more dandilions there are in a neighborhood one year, then unless there's a change in the way those homeowners respond to the issue, the more dandilions will be growing in that same neighborhood next year. What you simply need to do is to take a more active role in eliminating the mildew growth in your bathroom by cleaning it more often for a start, and changing from bar soaps to a non-lipid cleanser.

But, if you have no reason to believe that there's water leaking into your walls, why in God's good name would you start tearing your walls apart to deal with mold growth you have no reason to believe is even there?

This message has been edited. Last edited by: Nestor,
Jan 10, 2012, 09:30 PM
Originally posted by Nestor:

I think things are getting out of hand when people presume that just because mildew is growing in a tub/shower area it necessarily means there's water damage to the walls behind the tiling.

Not at all. Just a response to Rfv's information in which he says:

1. There is mold in the bathroom around the tile surround.
2. He is planning on removing the tile and installing new.
3. He would be doing the retile work no matter what.

All the recommendations to explore behind the tile after it's removal make sense (since the tile is coming out anyway). Removing tile frequently damages the backer behind it so if it's damaged or if it too shows signs of moisture damage, then it needs to be replaced too. And finally, if he's gone ahead and removed the existing backer it is an obvious next step to inspect the framing.

Aug 29, 2012, 02:02 AM
Mold Removal is neither time consuming nor expensive. Make sure that your bathroom is well ventilated so that air may cross and make air dry. Mold is only form in a wet or moisture place. To remove mold use vinegar, spray it on mold, wash it with water after sometime and scrub with sponge or cotton cloth. Mold will definitely disappear.

mold remediation great neck
Jul 08, 2013, 12:28 PM
Mold and Mildew are very common in bathrooms where humidity builds up.

My daughter's bathroom was the perfect example. Not enough ventilation from the window and adding additional ventilation features to my older home wasn't attractive. The mold would grow on the ceiling and walls above the shower and we would get mildew on the shower tile grout and caulking.

I used many of the cleaning and killing recommendations mentioned above to get rid of it (bleach, vinegar, hydrogen peroxide).

Then I protected the shower tile, grout, caulk and painted walls and ceiling with special self-cleaning coating. It claimed the coating surface resists the growth of mold and mildew, so I tried it.

So far so good - I remodeled and coated my daughter's moldy bathroom back in January 2013 and I haven't seen any mold or mildew since. It supposed to work for 6-months and I've gotten my 6-months out of it - Knock on wood! The self-cleaning coating can be found at

Hope this helps.
Jul 08, 2013, 01:01 PM
two spammers, no information. rich.

with the cost of inspection fiber-optic cameras down in the $60s at Harbor Freight with a newspaper or online 20% coupon, why would you NOT poke a half-inch hole someplace easily patched and look for trouble if you are going to do a full facelift? bathroom mold is like c-0ckr0ach3s, you see one, you have hundreds.

sig: if this is a new economy, how come they still want my old-fashioned money?
Jul 08, 2013, 02:03 PM
And to point out, the last real post (mine) was made in January 2012!