Can I use household bleach on the walls of my house?

Household bleach, the common name for chlorine bleach or sodium hypochlorite, functions as a powerful cleaning agent, commonly used for removing difficult stains, killing mould and maintaining white fabrics. Household bleach also has certain benefits for interior wall cleaning, if used safely and appropriately.

The use of household bleach is highly unnecessary for the routine cleaning of walls inside of a home. For routine cleaning, a less harsh solution like dish washing detergents and pH neutral cleaners, along with non-abrasive sponges or cloths, is more appropriate. Bleach can prove beneficial, however, if your walls have become infested with active mould or mildew. The chemicals in household bleach not only have ability to clean mouldy surfaces but also to completely disinfect the surface, which can prevent recurrence.

Never apply full-strength bleach to your walls, as this may permanently damage the paint or other surface, and the cleaning process may also jeopardise your own skin. The amount of dilution will depend on the amount of dirt and contamination, but as a rule, never apply more than 1/2 cup of bleach per gallon of water. For light instances of mould and mildew, you may only need to add 1/4 cup of bleach to a gallon of water.

Sodium hypochlorite is a highly abrasive chemical compound, and as such, you should always exercise extreme caution when using it for any cleaning task. The use of rubber or latex gloves can protect your skin. If applying the bleach to your walls with a spray bottle, you should also wear protective goggles in case any spray comes into contact with your eyes.

When applying bleach to an interior wall, you have two basic options. You can pour the diluted solution into a spray bottle and spray the wall directly, or you can apply it to a cloth and gently blot the surface, covering any dirt or mould. Never pour the solution directly onto your wall, and never blot with a dripping cloth (your cloth should only feel damp). Furthermore, do not rub or wipe the wall with your cloth, as you may damage the paint, wallpaper or wall board surface.

The bleach will require approximately 15 minutes to properly disinfect mouldy surfaces, so wait fifteen minutes before rinsing. To rinse your wall, use a second damp cloth or spray bottle containing only water. Even though the rinse contains no bleach, you still must not pour liquid directly onto your wall, as excess saturation can cause permanent damage. If you choose the spray bottle approach, follow up immediately by blotting the wall gently with a dry cloth or towel.

To dry your wall properly, place a dehumidifier nearby and turn it on using a "High" setting, or point a few high-powered fans at the wall to draw out moisture (opening a window can improve the effectiveness of this approach). Walls are highly porous, so towels alone will not dry them properly. You can also dry your walls by turning on a heater or improve your air circulation by turning on your air conditioner.