Vinegar vs Bleach for Mold: What Works and Where

Bleach for mold removal is the classic advice, and it is the one the EPA pushes back on most. In its Mold Course, the EPA says a biocide or mold-killing chemical is not recommended as a routine practice during mold cleanup. It allows that professionals may use one in some cases, for example when immune-compromised individuals are present.

The reason is simple. Killing mold is not the goal. The EPA says dead mold is allergenic and may cause allergic reactions in some people, so it is not enough to kill it; the mold must also be removed. The EPA also says that in most cases it is not possible or desirable to sterilize an area: some spores will always remain, but they won't grow once the moisture problem is fixed.

So for hard surfaces, the EPA's basic instruction is to scrub mold off hard surfaces with detergent and water, and dry completely. If you do choose bleach, the CDC says to mix no more than 1 cup of household laundry bleach in 1 gallon of water, and the EPA says to always ventilate the area and exhaust the air to the outdoors.

Texas regulators say the same thing about walls. The Texas Department of Licensing and Regulation (TDLR) states that merely applying a chemical such as bleach to drywall, without removing the mold source, is not a permanent effective solution.

Partly. The best lab evidence is a 2015 study in the International Journal of Environmental Research and Public Health that tested common cleaners against two mold types often found in indoor air. Household vinegar (4.0% to 4.2% acetic acid) inhibited the growth of Penicillium chrysogenum but not Aspergillus fumigatus. The authors concluded that vinegar may not be effective against the diverse fungal genera found in the indoor air environment, and that its lack of persistence may limit it to removal of fungal contamination on non-porous materials.

That study was a lab-dish test, not a real wall, so treat it as a sign of vinegar's limits rather than a final verdict. Extension services still suggest vinegar for small cleanups. Oregon State University Extension recommends wetting black or white mold with a half-water, half-vinegar solution, scrubbing until the mold is gone, and letting the area dry fully.

The practical takeaway: vinegar's real job is the same as detergent's. It helps you loosen and wipe mold off a hard surface. The scrubbing and drying do most of the work.

White vinegar for mold removal: where it makes sense

White vinegar for mold removal is a reasonable choice on:

• Glazed tile, glass, sealed countertops and shower doors
• Plastic and metal surfaces
• Finished or sealed hard surfaces where you can scrub and dry the spot

Those match the surfaces TDLR says can be cleaned: non-porous surfaces such as concrete, metal, glass, tile, and solid wood. Mold removal vinegar recipes online often promise more than that. Vinegar will not pull mold out of drywall paper or carpet backing, and it does nothing about the leak behind the stain.

The surface decides more than the cleaner does.

Non-porous surfaces (tile, glass, metal, plastic, sealed stone) can usually be cleaned. Mold sits on top, so scrubbing with detergent and water, vinegar, or diluted bleach can remove it.

Porous surfaces (drywall, carpet, ceiling tiles, insulation, upholstery) are different. The EPA says absorbent or porous materials, such as ceiling tiles and carpet, may have to be thrown away if they become moldy. TDLR says mold growth is difficult to clean from absorbent (porous) surfaces such as drywall, carpet, fleecy furnishings and insulation, so those materials should be removed and discarded.

Painting is not a shortcut either. The EPA says do not paint or caulk moldy surfaces, and TDLR adds that painting over mold is also not an effective solution. If your mold is on a wall, read our guide to mold on walls and drywall.

This is the one rule with no exceptions. The CDC says: never mix bleach with ammonia or other cleaners, because it will produce a poisonous gas. The EPA says the same: never mix chlorine bleach with other cleaning solutions or with detergents that contain ammonia.

The Washington State Department of Health explains the chemistry:

• Bleach + ammonia: toxic gases called chloramines are produced.
• Bleach + an acid: chlorine gas is given off, and the department lists vinegar among acid products, along with some glass cleaners, toilet bowl cleaners and drain cleaners.

So don't spray vinegar on a spot you just bleached, or the other way around. Pick one, rinse well, and air the room out before you use anything else.

For areas under 10 square feet, the EPA lists the minimum protective gear as gloves, an N-95 respirator, and goggles/eye protection. The EPA's home guide adds detail:

• Respirator: an N-95 respirator, available at many hardware stores.
• Gloves: long gloves that extend to the middle of the forearm. If you use bleach or a strong cleaner, choose gloves made from natural rubber, neoprene, nitrile, polyurethane or PVC.
• Goggles: goggles that do not have ventilation holes.

Use this only for a small patch, less than about 10 square feet, on a hard surface.

1. Check the size. The EPA says that if the moldy area is less than about 10 square feet (less than roughly a 3 ft. by 3 ft. patch), in most cases you can handle the job yourself. Bigger than that, see the next section.
2. Find and fix the water. The EPA says the key to mold control is moisture control. Fix the leak, drip or condensation first, or the mold comes back.
3. Gear up and ventilate. Put on the N-95, long gloves and unvented goggles. Open a window or run an exhaust fan.
4. Choose one cleaner. Detergent and water is the EPA's default. Or use half vinegar, half water, as Oregon State Extension suggests. Or, if you use bleach, no stronger than 1 cup per gallon of water. Never combine them.
5. Scrub, don't just spray. Remove the growth physically. Remember that dead mold is allergenic, so it has to come off the surface.
6. Dry completely. The EPA's instruction ends with dry completely. A fan or dehumidifier helps; see our dehumidifier for mold guide.
7. Watch the spot. If it returns within weeks, there is still a moisture source, possibly inside the wall.

The EPA's line is about 10 square feet. If there has been a lot of water damage, and/or mold growth covers more than 10 square feet, it points you to its professional remediation guidance. It also says to call a professional if the damage was caused by sewage or other contaminated water, and not to run your heating and cooling system if you suspect it is contaminated with mold.

Texas has its own size rule for licensing. TDLR says that in most instances, areas of visible mold less than 25 contiguous square feet in area may be cleaned or removed by people who are not licensed. Larger jobs generally need a licensed mold remediation contractor.

If you hire help, keep the jobs separate. Texas law says a license holder may not perform both mold assessment and mold remediation on the same project. Use a mold testing company if you need an assessment, and a separate mold removal company for the cleanup. You can confirm any license with our Texas mold license check, and see how we verify every company we list. For prices, see mold remediation cost.