Once you’ve seen the first signs of discoloration, you need to figure out how to remove mold from walls fast to keep it from spreading and causing both health and structural issues. Follow these tips and use the mold removal spray recipes below to get your mold situation under control.
Inspecting for Wall Mold
Just about every home develops mold at some point. Surprisingly, newer homes get it more often than older ones.
That’s because mold occurs in areas of higher humidity, and the tighter seals around windows and doors in new home construction keep in more moisture than drafty old homes.
Signs of Mold Growth
The most obvious sign of a mold problem is finding green, brown, orange or even black spots.
But there are other, less apparent signs:
- Cracked or peeling paint
- Discoloration
- A recurrent “soot” or black streaks, specks, or dots
- Bulging
- A musty, damp smell
Where You’ll Find It Growing
Mold on basement or exterior walls occurs when water vapor in the air meets a cold surface and turns the vapor into a liquid.
Bathrooms and laundry rooms develop mold because they’re typically very humid.
Other humid areas include the walls and ceiling near humidifiers and any room with a hot tub or jacuzzi improperly installed indoors.
Mold also grows where there is (or has been) a water leak. Places like the cupboards under sinks are very prone to it. Once a pipe has leaked, there’s a good chance mold will grow unnoticed within the wall until the problem requires expert removal.
Safe Removal Tips
1. Protect your skin. Wear rubber gloves to protect your hands from coming in contact with mold and mold removal sprays. Remove the gloves the instant you’re done, so you don’t spread the spores throughout your home.
2. Wear long sleeves and pants. Opt for old clothing and wash it in HOT water to kill any mold spores that wind up on your clothes.
3. Ventilate the area well. Open windows and doors while you’re working, so you aren’t inhaling the mold or mold removal spray.
4. Protect those with allergies or immune issues. If anyone in your house has a compromised immune system or a mold allergy, get them out of the house while you do this if possible. If that’s not an option, you can minimize their exposure by closing doors between rooms while you remove mold.
How to Get Rid of Mold on Painted Walls
Use the Natural Mold Removal Spray first and wait two days to see if the mold returns. If it does, move on to using the Stubborn Mold Removal Spray.
Natural Mold Removal Spray
Ingredients
- 2 tablespoons borax
- 1/4 cup white vinegar
- 2 cups hot water
Directions
- Combine the ingredients above in a bowl, stirring until the borax dissolves.
- Pour the mixture into a spray bottle and liberally apply on painted walls, tile or other non-porous surfaces.
- Scrub thoroughly and immediately wipe clean.
- Spray again and let sit 10 minutes before wiping dry.
Stubborn Mold Removal Spray
Do NOT use this bleach-based spray at the same time, or even on the same day, as any other cleaning product. There are some cleaning products you should never mix, and bleach is one of them. (Related: Dangerous Cleaning Product Combinations.)
Ingredients
- 1/4 cup bleach
- 2 cups warm water
Directions
- Open the windows to ensure adequate ventilation.
- Combine the ingredients above in a spray bottle and liberally apply on painted walls, tile or other non-porous surfaces.
- Scrub thoroughly and wipe clean.
- If any mold remains, reapply and let sit 15 minutes before scrubbing. Spray again then wipe with a clean, damp cloth.
- Direct a fan at the cleaned area to dry it quickly.
How To Remove Mold on Cement
Unfinished basements are common sites for mold growth. If your home has a basement, it’s a good idea to inspect the walls and floor several times a year, particularly in your area’s wet season.
For unfinished cement, concrete, or stone basement walls, go straight to the Stubborn Mold Removal Spray method above. Be sure to open all doors and windows in your basement, so neither loosened mold spores nor fumes from the spray get trapped in your home.
For finished basements, try the Natural Mold Removal Spray first on painted walls. If the walls are unpainted, see the next section on removing mold on drywall.
How to Remove Mold on Drywall
Mold can grow on unpainted surfaces like drywall and popcorn ceilings, too. These surfaces are porous, which means the mold not only builds on the surface but also threads its way into the structure of the drywall/ceiling material, too.
If mold returns after using both types of mold removal spray above (several days apart), you’ll need to replace the drywall.
How to Stop Mold from Growing on Walls
To get rid of mold on walls permanently, remove it using the steps above. Then, adopt the following practices to keep it from returning.
In Basements
- Open curtains daily. Sunlight is a natural mold killer.
- If your basement has windows and doors, open them a few minutes each day to allow air to circulate.
- Use fans or space heaters to circulate air in basements without windows.
In Bathrooms
- Use bathroom fans after every shower or bath for at least 10 minutes.
- Use a mold-prevention spray or squeegee after every shower. (Related: Homemade Daily Shower Spray.)
- Keep shower doors open to allow air to circulate. Plastic shower curtains should be shaken well to dislodge water droplets then left partially open.
- Replace damaged caulk or grout in your shower and tub immediately.
- Clean your bathrooms, kitchen, and laundry room weekly. Look for signs of moisture or leaks in cabinets. (Related: Bathroom Cleaning Checklist.)
In the Rest of Your Home
- Keep your home’s humidity levels in check. Overly humid air contributes to mold and mildew growth.
- Visually check your roof after severe storms for loose shingles or other damage that could allow water to enter your attic or home.
- Keep debris and junk away from your home’s foundation so water does not collect there and seep into your basement or under your home.
- Watch for signs of cracks in your foundation and contact foundation repair specialists immediately if you see any.
- Inspect your washing machine hose quarterly and replace it every five years even if it does not show wear. (Many homeowner insurance policies will deny claims for water damage if you don’t!)
Katie B of HousewifeHowTos.com says
I’ve had no difficulties ridding my basement bathroom of mould using these steps.
Korina Nomane says
Ihave mold in my room coming in the roof any ideas would be good
Katie B of HousewifeHowTos.com says
Fix the roof.
Delores Lyon says
Thanks for sharing these different recipes! I just noticed that the corner space between the walls and ceiling of my bathroom are an odd color. The last thing I want is mold damaging my home, so I am going to spend my Saturday getting rid of it. Hopefully these homemade cleaners will do the trick!
amy says
And thanks for the recipe, hopefully it does the trick.
Katie Berry says
Rich, Borax is a laundry booster that’s available at stores like Walmart or even your grocery store. It contains sodium tetra borate, a natural mineral that’s mined in the Mojave Desert. One brand name of borax is “20 Mule Team.” You can find it here on Amazon but, honestly, it costs MUCH less at grocery stores.
Andy says
Some great info here, a lot of people just don’t realise that condensation is one of the main causes of mould on walls. Prevention is a must, bleach and water help when cleaning but proper ventilation is key when it comes to battling mould issues. Really good article with some helpful tips. Thanks for sharing.
Shari says
We had a leak in a room and now there is a white coating on a wood armoire- is that mold?
Katie Berry says
No, that’s probably water damage to the wood. Here’s how to fix it. Let me know how it turns out!
Katie Berry says
That’s really something for a contractor to handle, Rebeca. I’m not skilled in that area. Sorry!
Katie Berry says
Thanks for sharing that tip, Marion!
Wilma Schoenheit says
I have mold in a closet next to the air conditioner filter. I’m wondering if it come from the attic and somethings leaking from Ac!
Katie Berry says
It could be something from above, or moisture building up inside the closet. You should probably schedule an AC tuneup to have it inspected.
Donna says
I live in a RV and the clothing closet always has mold and if you lean something against that wall then it gets mold on it. It happens every year. How to stop it.
chris says
dehumidifier
Maureen says
Donna might want to try putting damp rid in the closet. I hang it in my closets.
Katie Berry says
Damp Rid is wonderful. A box of sidewalk chalk works, too!
Beth says
I have mold on wood stained doors. Do your 2 methods work for them too?
Katie Berry says
Yes, but (there’s always a “but”, right?) don’t leave the solution in contact with the wood for too long or it might lighten the wood. It’s better to lightly reapply it several times than risk having a discolored spot from a heavy-handed application. 🙂
Rusty Mitchell says
I have water saturated baseboards in my bedroom about 6 inches up. I am getting an itchy throat but I know I’m not sick so it must be from mold.
I’m burning two essential oil diffusers to mitigate the bad air and I keep window open with two fans on high all day. Is there anything else I can do to keep my bedroom temporarily habitatble? My landlord is waiting for an appraisal to send in a mold clean out crew.
Thanks
Katie Berry says
Diffusers won’t mitigate mold spores in the air. Running your fan and keeping the windows open (assuming it’s not raining or terribly humid outside) will help. You might want to tape/tack tarp over the saturated areas to keep the mold spores contained. That won’t help dry it out, though, which might upset your landlord so you’ll have to choose between your health and his/her happiness.
stephanie says
Thank for the advise of removing mould of the wall. I live in the UK and not sure what to use instead of Borax or where I can buy it.
Any help in purchasing Borax, would be very helpful
thank you
Katie Berry says
Hello, Stephanie! Unfortunately, Borax is not available for sale in the UK due to different health and safety regulations but you can find substitutes (which are sodium borate, sodium tetraborate, or disodium tetraborate) that work almost as well, though. Look for “Borax Substitute” at Tesco in the cleaning aisle — both “Dripak” and “Clear and Natural” brands work equally well. They’re also available on Amazon. Here’s a link to the UK listing.
Katie Berry says
Bleach kills mold. There are plenty of scientific studies confirming this.
suha says
On My bedroom walls (near the window) and bathroom walls ..I’ve noticed moulds growing ..and it has also affected our skin ..we cleaned it then it came again …we are extremely upset with this problem…pls suggest good solutions..
Thanks
Katie Berry says
First, try cleaning using the instructions here. Then, be sure you’ve caulked properly around your bathroom windows and that you are running your bathroom fan for 15 minutes every time someone finishes bathing. If you continue to have problems, call a professional.
Carole says
I found oil of cloves kills the mould, Put 5ml oil of cloves in bucket of warm water and wash your walls – brilliant
Katie Berry says
Excellent tip. Thanks!
Jean says
In our RV we have a mould problem on the ceiling of the bathroom mostly in the winter when it is stored… I have tried to keep the vent open and closed.(no difference ) we use Driz.air to absorb moisture. Is the moisture coming from the toilet or/and bath drain? If I use the cleaning methods you suggest could I then paint the ceiling with special paint?
Katie Berry says
Once you’ve killed the mold you should use a primer designed to fight mold. I don’t know whether there’s a specific one for RVs but I’m sure an RV place could tell you.
Marii says
I live in an apt here in Mexico. The structure here is made of cinder blocks & cement. I notice black stuff is growing on the walls. Even more I’ve been cooking beans in the Crickpot for just a few months (July-January) usually with the windows open but this winter has been cold so the last few months ive cooked with all the windows shut closed. I notice all my walls including the bathroom are soaked. Now with minimal black creeping in various places does this mean that ALL my walls & ceilings need to be washed down. If so Im gonna need some help!
Katie Berry says
It could be mold or just plain mildew but, without seeing it, I really don’t know. Either way, it’ll keep spreading unless you clean it. Sorry!
Katie Berry says
I hope you feel better soon.
Katie says
I have mold that keeps forming in my single bedroom I share with my partner. The room is always cold my dad doesn’t use the heating . I’ve noticed when we wake in the morning they is water running down the walls. Ended up with mold forming round the corners/edges and window. I’ve wiped them and dried them also got a small dehumidifier but not resolved the situation… help?
Katie Berry says
Without heat, the temperature difference between the water (in pipes, the toilet tank, etc.) and the ambient air will cause condensation.
Katie Berry says
I can’t answer that because I haven’t tried Zinsser.
Kat says
Going to go for bleach had a pipe leak and it got the walls in a closet damp 4 inches high now its green almost 3 ft high. Can’t leave the door a open my cat will go in but I can put a fan and space heater in there space heater will shut off automatically after 15 minutes come back on in a half hr. I will pull the plug if I leave the house
Katie Berry says
If it’s that bad, I think you’re smart to go straight to the bleach solution. Good luck!
Katie Berry says
Hi Dan,
Sorry for the frustration about posting photos, but I’m sure you can understand that permitting such a thing could lead to all sorts of hassles since not everyone plays nicely on the internet.
Now, let’s talk about that basement problem! Keep in mind that I’m not a mold-removal expert or a structural engineer, so the info below is just what I’d personally do if I had problems with mold returning to basement walls.
First, Drylok is a quick go-to solution, but it usually fails in a couple of years despite what the warranty says. I trust you made sure the walls were dry before applying it, right? So that makes me wonder if the problem is condensation building up inside the basement and causing mold on the walls. Some things to check:
If you’ve checked all those things and the problem persists, it’s probably time to call the professionals. Good luck!
Claudia B. says
We used the natural mold removal spray (Borax, vinegar, water) on mold on painted walls inside a closet, using your instructions. It did a pretty good job, but most areas still have gray mold residue and a couple of areas still show black mold. What do you recommend? If the bleach method, how much time should go by before using it.
Katie Berry says
Hi Claudia,
You should wait at least 24 hours, or until the walls are completely dry, whichever is later. The reason for waiting is to ensure the vinegar from the first solution is dry and inactive, since mixing bleach and vinegar creates chlorine gas.
chris says
the tip about replacing the hoses on the washing machine also applies to the flex hoses on flick mixer sink taps too they have a tag with a manufacture date on them they also have a replacement date if your hoses haven’t been checked regularly by a plumber and replaced by the due date no insurance for burst pipes. they are the most common cause of water damage in kitchen and bathroom cabinetry.
Katie Berry says
Great point. Thank you!
Junell says
I have a cinderblock building that we have insulated and finished the walls with Sheetrock. Every year we have a powdery green mildew, I presumed, form on the walls during winter and early spring. We do not have heat or air in the building and only use it during summer trade. What can we do to prevent this from occurring and best way to remove and treat.
Katie Berry says
Hi Junell,
The only real way to stop that mildew from forming is with adequate air circulation. Without it, any moisture in the air will collect on the walls and cause mildew and possibly mold, too.