Removing Mildew from Grout

Maybe this works, but the fumes were overpowering even with ventilation. I would hesitate to recommend this.

Mark and Peg,
You are so right. The fumes can be really bad. But with repeated applications, it works. If you don't want fumes, consider Oxygen Bleach. There are no fumes at all.

Should I be concerned about the bleach affecting the color of my grout. It is a light tan (linen) color.

Thanks.

Matt,
You should to a small degree. I would test a small area.

Thanks Tim. Your paper towel trick was ingenious. After scrubbing for hours at deeply embedded mildew in my bathtub's grout, only a bit came out. I just tried paper towel soaked in bleach, and after twenty minutes 90% of it is already gone. Happiness!! :) :)

Should I be concerned that using bleach will break down the surface of my tiles?

Jessica,
Chlorine bleach will not harm glazed tile.

Will the bleach harm natural stone (travertine)? Thanks for the info.

Will this work on mildew that has grown on the bathroom floor behind a toilet. Is there something I can do about a toilet sweating and dripping on the floor.

Antresia,
Toilet sweating can be prevented by installing toilet tank liners. I got some from Home Depot for around $15 (in canada so your prices might be different). The package comes with thin sheets of styrofoam, glue(waterproof after 24-48 hours to dry)and instructions on how to cut it to fit the inside of your tank. It's also handy to have rubber gloves for cleaning the inside of the tank, a small cup & sponge to get excess water out, and a blow dryer to dry out the tank. As well a marker, long ruler, and sharp utility knife.
:) Cheers

Thank you so much Tim! You saved me from having to recaulk my bathtub. One question: I've read some places online that bleach doesn't kill the mold and that it will eventually come back. If I follow your tips on how to prevent mold, should I have any more problems? Do I need to treat my bathtub with anything else to prevent future mold outbreaks?

Tim, I had not thought about hard water deposits, and think that this is what is all over my glass shower door -- will the vinegar trick be the best on a glass surface too?
Thanks!

Along with the gray grout comment up there....i have a brown grout, would I be best off to just start off with the oxygen bleach?
Also, I am a brand new homeowner and I am not sure that the grout is correct in my bathroom. It is super rough, and seems like there should be some sort of caulking instead inside/around the bathtub. (Maybe I just think that because that is how all my bathtubs were growing up) Is this something I should consider, or even apply OVER the grout?? I'm very confused.... so any advice would be greatly appreciated

I have a new shower stall that has tile with a beige grout. There is a red stain that stains the grout in a couple of places. A friend told me it is a bacteria called serratia marcessans that is staining the grout. The builder of our new house has removed the grout and re-grouted and re-sealed it twice, but the red keeps coming back. Any suggestions?

Thank you so much for your great advice! Questions... I thought I was going to have to regrout. I tried using my Clorox Oxy Clean spray and didn't have much luck today. However, tomorrow, I am going to buy Bar Keeper's friend (is this okay to use, it's the most effective cleaner I have used besides the Lysol Mildew remover), vinegar, bleach. Someone mentioned the terrible smell w/ the bleach, could I use a Bleach gel pen instead? It's less messy and go directly on the grout. Will I have to put a towel over the gel as well if it's okay to use?

Thanks so much for your help!!!!

Hi Tim,

Thanks for the great information. Is it possible to use distilled white vinegar to remove mildew from grout intead of bleach?

Hi Tim,
I love your site.
I have a question. I'm at the end of my rope with this mildew issue. I've used bleach, bleach pens vinegar (not the precise way that you outline above) and I've gotten no results. Before I embark on this latest version I just wanted to ask you what if it appears that the mildew is actually growing UNDER the caulking between the tiles? Will this method work owr will I have to remove the caulking and start from scratch. Your insight is most appreciated.
Best,
Marla

Would peroxide work in place of bleach? I Market clean air and water products and I have just about got chlorine bleach out of my house.

Thanks for the great tip. My shower is only about two years old and was kept clean so it was a fairly light job, and with just a little scrubbing I was able to get all the soap film and mildew out after letting the vinegar soak for about 6 hours - didn't even have to use the bleach.

What was your answer to will bleach harm natural stone? My shower is natural stone and the grout and caulking have mildew. I am afraid to clean with bleach and do not know what to use. Please advise. Thanks

If Mark & Peg above got overpowering fumes, they may not have adequately rinsed between the vinegar and the chlorine bleach. Mixing bleach and vinegar will release chlorine gas, which you really don't want. The instructions are good - remove all traces of vinegar. Rinse a lot!

We've followed your instructions using the saturated paper towels. How long should the grout air dry before we recaulk? What kind of caulk do you recommend for a shower where the wall tile and the floor tile come together?
Thank you.

Hi is there any risk of the bleach staining painted pattern on blue tiles. Also, the previous owner appears to have run a line of solastic down the grout in the shower corner. Not sure why they would have done this? will the mould come out of the solastic?

Antresia,
I also have the same problem as you, butl I think you have it worse. I also sweat on the toilet but mine never comes to dripping wet on the floor!!

Maybe I have better ventilation.

Thanks for this advice Tim, it worked a treat after about 3 hours which I spent having a quiet couple of beers.

Beats re-grouting any day (which is what my wife thinks I did!)

Thanks again,

al

Just looking over this... make sure you follow directions and thoroughly remove all traces of vinegar from the walls before you move onto bleaching. If you can still smell vinegar, there's too much. If bleach and vinegar, ammonia or another acid mix, they produce chlorine gas, which can be permanently harmful or lethal, depending on the amount you inhale.

Will the bleach harm natural stone (travertine)? Thanks for the info.

Tim, it worked like a charm! My grout looks as good as the day it was laid!!!

One thing I'd add to the comments is that there may be an easier way to paper the wall. I think I'd try taping the roll of towels to the top of the shower and rolling them down the wall, and then wetting them. It would be faster than putting the towels on one at a time. That took me some time, and of course I didn't think of the "better way" until I was finished!

Great tip, great results! Truly amazing.

I want to vouch for the effectiveness of this technique. The only issue is the fumes from the bleach. Even with adequate ventilation it can seem overpowering so you may have to work in sections or use oxygen bleach as Tim mentioned. Leaving the paper towels on overnight for a total of about 12 hours had grout and caulk so crusted with mildew I thought it was beyond repair looking virtually as new.

Haven't seen your answer about your cleaning solutions on Travertine or marble. What 'cha think?

Once removed, would an application of bathroom type caulk that changed the profile help build-up in the future?

The bleach/paper towels worked beautifully! Now, after rinsing and wiping down the walls, do I need to reseal the grout?
Does the bleach weaken the grout?

Hi, Tim. Last year we started to get a leak between tub and tile. My husband applied silicone over the grout and now we are really getting a mess. I understand how to clean the grout, but what do I do with the silicone he applied? Thanks...great website!

I have an old yellow bathtub and cream tiles. I need to remove the caulking and need to know what to use on the mildew that will not discolor the tub.

A sweating tank is always caused by a slow leak in the flap. As fresh cold water flows in to top up the tank it becomes colder than the room and condenses water from the air.

Replace the flap, wiping down any grit where it seats, and the sweating will stop.

One product to keep mildew from returning is Tilex "Mildew Root".
Harder to find than the regular Tilex mildew cleaners, but works a lot better. I've found it at groceries and Target. Walmart type stores but only about one in four carry both types. http://www.tilex.com/mildew

We're having a new bathroom built at this minute. Is there something you can add to grout before it is applied that will prevent mold and mildew? Thanks. David

This was an EXCELLENT solution - thank you SO much!!!

I left the stuff on my walls and went out for a couple of hours with the window open, but on a rainy day to keep the humidity up/towels wet. I was amazaed how well this worked!! I never thought my tiles and grout would look this good again!!!

What about the effects of all that harsh cleaner on a septic system?

I have a shower & tub insert over my original tile(bathfitters) will this discolor the insert?

I have read your comments on cleaning grout. Will This process affect the carrera marble tiles I Have?

Sandra

I read all over the place that mixing bleach with vinegar is poisonous. Don't do it!

I'm going to try this but it might be too late for me. I had stains so bad that I removed the grout and re-grouted with a silicone grout that was supposed to resist mildew. I still have black stains on the new grout as well as on the tiles. The corners are especially bad. Hope this works, if you have further tips please post. I don't know why the mildew is so bad in there.